Sound Practices Mailing List Files - Volume 2
=========================================================================
From: Frank_Deutschmann@trepp.com
Subject: [JN] GADS!
Date: Fri, 18 Feb 2000 16:36:19 -0500
Source: Sound Digest Archive v02.n454
*ONE* post in a zillion years, and I screw the pooch....
First, the equation should be:
%eff = k * Vb * f3^3
(NB the f3 is CUBED: the essence of the whole deal!)
Second, a more reasonable value for k is 2.6x10^-6 (for Vb in cubic feet,
efficiency as a percent, and an electrodynamic driver in a closed box).
(Yeah, I know how to work a calculator, trust me.)
Third, 100dB SPL (6.31%eff) with a f3 of 100Hz seems, from the above, like
it should require about 2.5 cubic feet. But then again, I'm having trouble
working a calculator today -- and the english-metric conversions are
killing me.... (Yeah, I be a rocket scientist -- but I don't work for
NASA.)
- -frank, vaguely remembering that someone once told me to check my work
before pushing the big red button....
Frank Deutschmann
02/18/2000 02:15 PM
To: "Greg Monfort" <wingracer@email.msn.com>
cc: <sound@deliverator.io.com>
Subject: Re: Fw: [JN] SP-mw1 help (Document link: Frank Deutschmann)
Alas poor Hoffman, distraught over three loves; would that he could have
all three in one, but it is not to be!
100dB SPL (6.31% eff) @ 100Hz would require (minimum) approximately 110
cubic feet for a sealed box, or 55 cubic feet vented; dropping the
efficiency requirement to 92dB SPL (1% eff) @ 100Hz would shrink the box
down to approximately 17 cubic feet sealed or 9 cubic feet vented.
Hoffman's Iron Law relates the three quantities of efficiency,
low-frequency -3dB point, and box size by way of an efficiency constant;
for efficiency in percent and size in cubic feet the Law is stated as
follows:
%eff = k * Vb * f3
where the efficiency constant k ~= 7.1x10^-5 for direct electrodynamic
radiators in sealed boxes or 1.4x10^-4 for vented boxes.
%eff can be related to db SPL with:
db SPL = 112 + 10 * log(%eff / 100)
note that 92 dB SPL equals 1% efficiency.
Ahh, the tales Hoffman tells!
- -frank, wondering if the muse is horny....
"Greg Monfort" <wingracer@email.msn.com>@lists.io.com on 02/18/2000
02:27:21 AM
Sent by: owner-sound@lists.io.com
To: <sound@deliverator.io.com>
cc:
Subject: Fw: [JN] SP-mw1 help
Just punching numbers into a spreadsheet, I couldn't get any realistic T/S
numbers that give 100dB / 100Hz, so horn loading seems to be the only way
to
go.
GM
- ----- Original Message -----
>
> What i could use help on is a midrange that can do 100 to 1kHz at 100dB.
>
> mike wurtz
=========================================================================
From: Timo Christ <carnivor@uni-bremen.de>
Subject: [JN] gaincard type amps
Date: Wed, 24 Nov 1999 20:33:08 +0100
Source: Sound Digest Archive v02.n344
Hi all !
a few weeks ago i told that i'd report about my "Gaincard" style
amplifier.
Sorry for being so long winded about this but now as the subject has
risen again i took the time to update my webpage.
Please refer to
http://www-user.uni-bremen.de/~carnivor/hifi/hifi.html#Gaincard
Thank you.
Most details about the internals are given there, questions welcome.
A lil' schematic is there,too.
I'll be at the Triode show in Arhus in July and hopefully show the amp
there (if i can get the car).
See you there !
Timo
- --
Timo Christ
EE Student University of Bremen, Germany
carnivore@uni-bremen.de
http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: Paul Joppa <pj@bottlehead.com>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Mon, 09 Apr 2001 21:08:35 -0700
Source: Sound Digest Archive v02.n862
For amplifiers that use no negative feedback, built by people
that think every tube has a particular sound, it's not really
practical to fix the gain as a design parameter. You pick your
favored tubes, and live with the gain that results. I am
certainly unwilling to compromise the sound in order to adjust
the gain of the amp - that's what gain controls are for!
It appears that the usual range of sensitivities is from 200mV
to 2vRMS for full power output (which may range from 1 watt to
perhaps 100 watts). I gather that European amps are slightly
more likely to have higher sensitivity.
According to Jensen Transformers, the nominal maximum rms
voltage is 2v on professional studio gear, to 500mV in consumer
stereo and TV gear.
Most CD players will provide 2v rms or more at clipping, and
will drive most 300B amps into clipping with a passive preamp.
That seems adequate to me, but most people would rather put the
gain control vertical and feel they have some reserve, just in
case.
- -Paul Joppa
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Mon, 09 Apr 2001 21:34:25 +0200
Source: Sound Digest Archive v02.n862
Hello Timo,
>Yes... only that standards ain't gonna happen in DIY audio... :-)
Careful, standards grow strange ways....
Ever consider the diameter of the inner hole of a CD ?
It is exactely the size of a "dubbeltje" (Dutch 10 cent coin, say 4 dollarcent)
It is just taken By Philips and Sony engineers as something bigger then the
6 mm of vinyl, and something acceptably small in order not to sacrifice
space from the disc......
Now back to the gain issue, more funny "standard" stories may follow in
Arhus, with some good beer.
>> 4/ x30 in the PAmp means most preamps have to be turned WAY down - which
>> doesn't do the gain structure (and sound) any good at all - but x5 means you
>> could be struggling for overall gain with a low output MC.
>
>I agree. For me, even unity gain or x2 is enough, but i'm using only
>high output sources (DACs). ... and an active preamp (5687 WOT).
So a single triode could be enough
>The nice thing is that i could easily change the tube stage in the
>hybrid amp that i'm planning. Load for the tube is about as easy as it
>gets and i will have all options concerning the power supply voltage and
>current with SuperReg regulation... heater is going to be CCS regulated
>(RonanReg style but without series regs).
>I will put octal sockets in first and build hole size reducers for
>loctal and noval (similar to what Doc Bottlehead sells) or maybe
>adapters from loctal and noval to octal. That would rock ;)
>I hope that i can get this amp ready for the Triode Fest. We could
>experiment with different tubes pretty easily. With a neutral and
>constant output stage the impact of different driver tubes' sound will
>hopefully be recognizeable.
You bet !
>I am especially thrilled to experiment with pentode voltage gain stages.
>:-)
Keep us updated, I am starting to become curious (that boy must have loads
of time to build......)
Guido
>Regards
>Timo
>--
> / /--' Timo Christ carnivore@uni-bremen.de
> / /<-. EE Student University of Bremen, Germany
>__/ /__/ Horns 'r more fun:
> ' http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: Allen Wright <AllenVSE@compuserve.com>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 06:59:40 -0400
Source: Sound Digest Archive v02.n862
Guido wrote:
>>>If it became some sort of a standard it would allow critical
comparisons...
Agreed, but that holds for all "standard" gains :-)<<<
But there are NO standard gains - and I'm trying to promote one.
>>>It doesn't have so much gain that line stage noise becomes a problem...
But the noise is no issue, as for one reason, somewhere all gain stages
neccessary are in the system anyhow<<<
Of course a system has to have a given amount of gain to work with the
relevant sources used - but line noise IS a problem (with hi-gain
poweramps) because it's generated after the gain control.
Try demo'ing a slightly noisy tube line stage into a 40dB gain poweramp on
94 dB/w speakers...that was a problem!
>>>Can't seem to sell my WE 300Bs so may just have to fire up something...
What is your price ? What age are they ?<<<
They are one hour old - and from the new production - not old NOS. I am
asking DM1500 for a matched pair and they owe me this - but if I don't get
it they go into proto SE'ers.
Allen (VSE)
=========================================================================
From: Christian Rintelen <christian@rintelen.ch>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 14:05:06 +0200
Source: Sound Digest Archive v02.n862
Paul Joppa wrote:
> According to Jensen Transformers, the nominal maximum rms
> voltage is 2v on professional studio gear, to 500mV in consumer
> stereo and TV gear.
In order to get full 24 bit resolution (0 dB at the A/D converter)
with its FDS-366 crossover, BSS specifies an input signal level of
+20 dBu (7.7 V RMS), the output will also be +20 dBu into 600 Hz
or higher.
Jensen specifies its studio line-out transformers for a max. level
of 27 dBU @ 20 Hz, the Jensen 1:1 line input transformers have +20
dBu @ 20 Hz level handling capacity.
Seems more likely to me that +20 dBu (7.746 V rms) are the actual
/ nominal maximum rms for pro gear...
FWIW, ©
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 15:39:34 +0100 (BST)
Source: Sound Digest Archive v02.n862
Timo asked:
>Can someone recommend inexpensive + good + easy to find triodes with a
>gain close to 10 ?
Battery valves DF91 triode connected or DC91 have a mu around 10.
The DF91 comes in a 25 mA filament version, the DF96. They have B7G
sockets. You can therefore run the heaters from a single D cell for
hours! There is also the older octal range, DF33 etc. And the 1G4 or
something similar is a geniune DHT with a mu about 8. They work really
well, but watch out for microphony. Some of the older 4 V British
mains valves, like AC/P, ML4, ML6, also have low gain. These were
sometimes used as small output valves. There is also the 6S4, if I
remember right. But you are right the 'common' variety have a much
higher gain. The ECC82 has a lower gain, but it is not very linear.
Try also the old 2 V battery valve range, there are several triodes there.
They are not so microphonic as the 1.4 V range and can stand higher anode
currents.
I'm planning a 1 W push pull battery amplifier using the DF91 and two
DL94s, to be entirely run from batteries.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
=========================================================================
From: Timo Christ <carnivor@uni-bremen.de>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 16:23:24 +0200
Source: Sound Digest Archive v02.n862
Hi Guido, all,
[i wrote what's in > > and Guido wrote the > lines]
> >I agree. For me, even unity gain or x2 is enough, but i'm using only
> >high output sources (DACs). ... and an active preamp (5687 WOT).
>
> So a single triode could be enough
Yes.
Can someone recommend inexpensive + good + easy to find triodes with a
gain close to 10 ?
I still have no tube data book to browse through...
The duncanamps.com searchengine searches only for the tube name and not
for parameters.
> >I am especially thrilled to experiment with pentode voltage gain stages.
> >:-)
>
> Keep us updated, I am starting to become curious (that boy must have loads
> of time to build......)
hmm... recently i read on Remco's website (take a look:
http://www.ultranalog.com ) that planning is always two years ahead of
the workbench...
It's not that much here (i guess Remco is faster, too), maybe 3-4
months, and i'm a fast worker. ;)
The amp will not be finished toooo early.. speaker project comes first.
I hope to have it ready for Arhus. Gotta swim against the stream, eh?
Remember, the best output transformer is the 2N3055? :)
Regards
Timo
- --
/ /--' Timo Christ carnivore@uni-bremen.de
/ /<-. EE Student University of Bremen, Germany
__/ /__/ Horns 'r more fun:
' http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: "P de R. Leclercq" <triode@freenetname.co.uk>
Subject: RE: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 18:17:10 -0700
Source: Sound Digest Archive v02.n862
Other low-mu possibilities include 6BX7 (10) a double triode that does need
1.5A of heater current. 6S4 has mu of 16, and 8W dissipation; it can stand
550V.
Another little known type is EC93 (6BS4). This is a 7-pin type with mu of
15. Unlike most low-mu types, it is quite low capacitance (1.5pf Ca-g) and
has reasonable gm (8).
The alternative is to consider triode-strapping small output pentodes.
GEC's A2134 offers mu of about 10 and 9W Pa. It is fairly linear as a
triode, can stand 300V, but can be microphonic.
Paul Leclercq
- -----Original Message-----
From: owner-sound@lists.io.com [mailto:owner-sound@lists.io.com]On
Behalf Of Simon Busbridge
Sent: 10 April 2001 07:40
To: Timo Christ
Cc: evaguido; joe net
Subject: Re: [JN] Re: Gain of typical 300b amp
Timo asked:
>Can someone recommend inexpensive + good + easy to find triodes with a
>gain close to 10 ?
Battery valves DF91 triode connected or DC91 have a mu around 10.
The DF91 comes in a 25 mA filament version, the DF96. They have B7G
sockets. You can therefore run the heaters from a single D cell for
hours! There is also the older octal range, DF33 etc. And the 1G4 or
something similar is a geniune DHT with a mu about 8. They work really
well, but watch out for microphony. Some of the older 4 V British
mains valves, like AC/P, ML4, ML6, also have low gain. These were
sometimes used as small output valves. There is also the 6S4, if I
remember right. But you are right the 'common' variety have a much
higher gain. The ECC82 has a lower gain, but it is not very linear.
Try also the old 2 V battery valve range, there are several triodes there.
They are not so microphonic as the 1.4 V range and can stand higher anode
currents.
I'm planning a 1 W push pull battery amplifier using the DF91 and two
DL94s, to be entirely run from batteries.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
=========================================================================
From: "eric elghammer" <aryxaudio@lycos.com>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 12:41:25 -0700
Source: Sound Digest Archive v02.n863
- --
On Tue, 10 Apr 2001 16:23:24
Timo Christ wrote:
>The duncanamps.com searchengine searches only for the tube name and not
>for parameters.
Hi Timo - TDSL has a feature named 'parameter search', as least my version (1.0.1.26) does; hit Ctrl
-S, or click on search in the toolbar. Eric
Get 250 color business cards for FREE! at Lycos Mail
http://mail.lycos.com/freemail/vistaprint_index.html
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 21:07:24 +0200
Source: Sound Digest Archive v02.n863
Hi Allen, others
At 06:59 10-4-01 -0400, Allen Wright wrote:
>Guido wrote:
>
>>>>If it became some sort of a standard it would allow critical
>comparisons...
>
>Agreed, but that holds for all "standard" gains :-)<<<
>
>But there are NO standard gains - and I'm trying to promote one.
I know what you are pointing at, but any gain could become a standard,
assumed it is widely accepted......
>>>>It doesn't have so much gain that line stage noise becomes a problem...
>
>But the noise is no issue, as for one reason, somewhere all gain stages
>neccessary are in the system anyhow<<<
>
>Of course a system has to have a given amount of gain to work with the
>relevant sources used - but line noise IS a problem (with hi-gain
>poweramps) because it's generated after the gain control.
Yes, you are right here
>Try demo'ing a slightly noisy tube line stage into a 40dB gain poweramp on
>94 dB/w speakers...that was a problem!
Yup ! (not to mention the hum....)
Some preamps therfor have a passive output. Problem is that their active
outputs always were lousy, some exceptions present however.....
>>>>Can't seem to sell my WE 300Bs so may just have to fire up something...
>
>What is your price ? What age are they ?<<<
>
>They are one hour old - and from the new production - not old NOS. I am
>asking DM1500 for a matched pair and they owe me this - but if I don't get
>it they go into proto SE'ers.
OK, At present they do $900 pair, am I correct ?
greets
Guido
>Allen (VSE)
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 21:09:25 +0200
Source: Sound Digest Archive v02.n863
Hi Timo
I wrote:
>> So a single triode could be enough
and Timo answered
>Yes.
>Can someone recommend inexpensive + good + easy to find triodes with a
>gain close to 10 ?
>I still have no tube data book to browse through...
>The duncanamps.com searchengine searches only for the tube name and not
>for parameters.
True
Try to look for liearity too, as you have to generate huge swing, that
counts too. The driver should have low thd, preferably below 0.5% at full drive
>> >I am especially thrilled to experiment with pentode voltage gain stages.
>> >:-)
>>
>> Keep us updated, I am starting to become curious (that boy must have loads
>> of time to build......)
>
>hmm... recently i read on Remco's website (take a look:
>http://www.ultranalog.com ) that planning is always two years ahead of
>the workbench...
>It's not that much here (i guess Remco is faster, too), maybe 3-4
>months, and i'm a fast worker. ;)
:-)
>The amp will not be finished toooo early.. speaker project comes first.
>I hope to have it ready for Arhus. Gotta swim against the stream, eh?
Yes, sometimes
>Remember, the best output transformer is the 2N3055? :)
I do not know that one. Which primary impedance does it have ?
Guido
>Regards
>Timo
>--
> / /--' Timo Christ carnivore@uni-bremen.de
> / /<-. EE Student University of Bremen, Germany
>__/ /__/ Horns 'r more fun:
> ' http://www-user.uni-bremen.de/~carnivor/
=========================================================================
From: Remco Stoutjesdijk <remco@ultranalog.com>
Subject: Re: [JN] Re: Gain of typical 300b amp
Date: Tue, 10 Apr 2001 21:58:05 +0200
Source: Sound Digest Archive v02.n863
> >The duncanamps.com searchengine searches only for the tube name and not
> >for parameters.
If you download the applet (windoze, sorry Timo you'll have to run it on
your 2nd machine) you'll find that searching by parameter IS possible in
there. Not linearity though, but hey, just apply feedback ( for the
ignorant: kidding! )
> >It's not that much here (i guess Remco is faster, too), maybe 3-4
I have a new record: built an amp within 3 hours of the conception of
the idea ;-)
But that was switching sand.
> >Remember, the best output transformer is the 2N3055? :)
>
> I do not know that one. Which primary impedance does it have ?
Vbe/Ib...
Remco
- --
http://www.ultranalog.com
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: RE: [JN] Re: Gain of typical 300b amp
Date: Wed, 11 Apr 2001 07:03:38 +0100 (BST)
Source: Sound Digest Archive v02.n864
Paul,
How linear is the EC93? It seems like an interesting little valve.
Simon
PS I forgot to mention the subminatures, there are some really nice low mu
triodes there (thanks to 'Viking' Kurt for making many of us aware of
these).
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
=========================================================================
From: TubeGarden@aol.com
Subject: [JN] Gain pain explained
Date: Tue, 10 Apr 2001 00:19:11 EDT
Source: Sound Digest Archive v02.n862
- --part1_2b.13b3b399.2803e3bf_boundary
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Greets!
Crank it up!
Turn it down!
The volume control gives a sense of control to people with neither.
Some people just listen as it comes.
Seems OK to me :)
Happy Ears!
Al B^}
- --part1_2b.13b3b399.2803e3bf_boundary
Content-Type: text/html; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
<HTML><FONT FACE=arial,helvetica><BODY BGCOLOR="#ffffff"><FONT SIZE=2>
<BR>Greets!
<BR>
<BR>Crank it up!
<BR>
<BR>Turn it down!
<BR>
<BR>The volume control gives a sense of control to people with neither.
<BR>
<BR>Some people just listen as it comes.
<BR>
<BR>Seems OK to me :)
<BR>
<BR>Happy Ears!
<BR>Al B^}
<BR>
<BR></FONT></HTML>
- --part1_2b.13b3b399.2803e3bf_boundary--
=========================================================================
From: "Murray Leshner" <multi-volti@softhouse.com>
Subject: [JN] gapped inductor but no DC
Date: Fri, 7 Jul 2000 09:21:30 -0400
Source: Sound Digest Archive v02.n598
A gap in an ac-only inductor core 'linearizes' it...helps keep inductance
constant over different range of voltage...iron core inductor with no gap
would exhibit varying inductance with varying voltage across the coil
because permeability of core varies with flux level...
With a gap you don't end up saying "What the flux is wrong with my
inductance?"
Murray
=========================================================================
From: "Murray Leshner" <multi-volti@softhouse.com>
Subject: [JN] gapped inductor but no DC
Date: Fri, 7 Jul 2000 09:21:30 -0400
Source: Sound Digest Archive v02.n599
A gap in an ac-only inductor core 'linearizes' it...helps keep inductance
constant over different range of voltage...iron core inductor with no gap
would exhibit varying inductance with varying voltage across the coil
because permeability of core varies with flux level...
With a gap you don't end up saying "What the flux is wrong with my
inductance?"
Murray
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 09:41:14 -0700
Source: Sound Digest Archive v02.n789
Hello Joes:
The following is Menno van der Veen's response to my inquiry as to
whether Plitron can wind gapped OTs for PP applications.
> Yes, we can build gapped toroids for PP aplication, leaving more room for
> any DC-inbalance of the tubes, however with smaller primary inductance (of
> course.
Bill - PEARL, Inc.
=========================================================================
From: "PEARL Cust Serv" <custserv@pearl-hifi.com>
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 11:13:15 -0700
Source: Sound Digest Archive v02.n789
Christian Rintelen wondered:
> gapped toroids? Huh?!? I always thought they used some kind of baked
> (amorphous) powder for their cores. How will they manufacture a controlled
> gap?!?
>
> Christian
While some toroids are made from "pressed mud," the sort I'm talking
about are tape wound. Once impregnated, they can readily be cut, shimmed and
re-assembled for the winding of coils
Bill - PEARL, Inc.
> PEARL Cust Serv wrote:
>
>> The following is Menno van der Veen's response to my inquiry as to
>> whether Plitron can wind gapped OTs for PP applications.
>>
>> > Yes, we can build gapped toroids for PP aplication, leaving more room for
>> > any DC-inbalance of the tubes, however with smaller primary inductance (of
>> > course.
>
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 12:58:03 -0500
Source: Sound Digest Archive v02.n789
>gapped toroids? Huh?!? I always thought they used some kind of baked
>(amorphous) powder for their cores. How will they manufacture a controlled
>gap?!?
i assume they use tape wound cores which are identical in manufacture as
C-cores... think of a C-core as a flattened toroid with a cut so a bobbin
can be added to the flattened section
the powdered cores you speak of can also be made with various gaps... the
cool thing there is the gap is evenly distributed throughout the core!
i wonder if this may not be a great way to do gapped toroids (traditionally
they are cut, spaced assembled back together and boxed)
good luck on your engineering revisions tho' :-)
dave
=========================================================================
From: John Levreault <jlevro@mediaone.net>
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 13:48:55 -0500
Source: Sound Digest Archive v02.n789
dave slagle wrote:
>
> the powdered cores you speak of can also be made with various gaps... the
> cool thing there is the gap is evenly distributed throughout the core!
...but the perm is a LOT lower.
JL
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 15:19:49 -0500
Source: Sound Digest Archive v02.n789
>...but the perm is a LOT lower.
>
>JL
yeah... but i have to wonder... isn't the perm related to the gap?... in
other words, why not introduce a smaller distributed gap... i am speaking
purely hypothetically here, but at some point between a solid block of
nickel, and the low perm version there has to be a compromise that might
work for audio here?
i've looked at a few of the powdered cores, and they all seem to be low
perm low flux, but i have to wonder if thats dependant on the needs for
their actual use?
i have to believe at some percentage of nickel (steel or whatever) and
distributed gap, you could match the properties of a cut gapped toroid?
now cost on engineering such a beast... thats another topic.
any real world sonic gains???? i dunno...
will it ever happen... probably not.. but its an interesting thought none
the less.
or is there a huge leap in the way the material behaves from strip to
powdered form (lets consider the non-oriented materials)??
dave
=========================================================================
From: Christian Rintelen <christian@rintelen.ch>
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 18:34:53 +0100
Source: Sound Digest Archive v02.n789
gapped toroids? Huh?!? I always thought they used some kind of baked
(amorphous) powder for their cores. How will they manufacture a controlled
gap?!?
Christian
PEARL Cust Serv wrote:
> The following is Menno van der Veen's response to my inquiry as to
> whether Plitron can wind gapped OTs for PP applications.
>
> > Yes, we can build gapped toroids for PP aplication, leaving more room for
> > any DC-inbalance of the tubes, however with smaller primary inductance (of
> > course.
=========================================================================
From: evaguido <EvaGuido@iaehv.nl>
Subject: Re: [JN] Gapped Toroid OTs for PP Amps
Date: Mon, 22 Jan 2001 20:48:56 +0100
Source: Sound Digest Archive v02.n789
At 18:34 22-1-01 +0100, Christian Rintelen wrote:
>gapped toroids? Huh?!? I always thought they used some kind of baked
>(amorphous) powder for their cores. How will they manufacture a controlled
>gap?!?
I guess they cut it, with tools they use for diamonds or so.......
Guido
>Christian
>
>PEARL Cust Serv wrote:
>
>> The following is Menno van der Veen's response to my inquiry as to
>> whether Plitron can wind gapped OTs for PP applications.
>>
>> > Yes, we can build gapped toroids for PP aplication, leaving more room for
>> > any DC-inbalance of the tubes, however with smaller primary inductance (of
>> > course.
>
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: [JN] gap size...
Date: Fri, 24 Mar 2000 10:43:27 -0500
Source: Sound Digest Archive v02.n494
>Further I believe that all good wide band transformers need to have a small air
>gap. As far as I know this is one of the main "secrets" in high quality
>audio transformers.
>But I also know that the size of this gap is extremely critical , that might be
>the reason that some ignores it ?
Kurt
can you point me to some reference on this???
or try to explain the logic behind it?
just curious...
dave
=========================================================================
From: John Levreault <jlevro@mediaone.net>
Subject: Re: [JN] gap size...
Date: Fri, 24 Mar 2000 11:23:51 -0500
Source: Sound Digest Archive v02.n494
dave slagle wrote:
>
> >Further I believe that all good wide band transformers need to have a small air
> >gap. As far as I know this is one of the main "secrets" in high quality
> >audio transformers.
> >But I also know that the size of this gap is extremely critical , that might be
> >the reason that some ignores it ?
>
> Kurt
>
> can you point me to some reference on this???
>
> or try to explain the logic behind it?
>
> just curious...
>
I think this idea goes back to Partridge, who still use it even on PP
iron.
JL
> dave
=========================================================================
From: Robert C Chambers <rchamber@norwich.edu>
Subject: Re: [JN] gap size...
Date: Fri, 24 Mar 2000 11:25:24 -0500 (EST)
Source: Sound Digest Archive v02.n494
Hello Dave, Kurt -
There is some information on calculating pp and se transformers at
Mikkel Simonsen's website at
http://home5.inet.tele.dk/mcs
Mostly formulas for calculating things, including gap width, but with not
much supporting theory. The material was translated from (I think they
were) two German texts which are listed.
Regards,
Robert
On Fri, 24 Mar 2000, dave slagle wrote:
>
> >Further I believe that all good wide band transformers need to have a small air
> >gap. As far as I know this is one of the main "secrets" in high quality
> >audio transformers.
> >But I also know that the size of this gap is extremely critical , that might be
> >the reason that some ignores it ?
>
> Kurt
>
> can you point me to some reference on this???
>
> or try to explain the logic behind it?
>
> just curious...
>
> dave
>
>
>
=========================================================================
From: dslagle@earthlink.net (dave slagle)
Subject: [JN] Gap size...
Date: Fri, 24 Mar 2000 13:14:27 -0500
Source: Sound Digest Archive v02.n494
Just a clarification...
I took kurts comments as to suggesting using small airgaps as opposed to
big ones...
JL's bringing up partridge... made me realize that may not be what kurt meant...
rather that all trannies should have a gap whether they carry DC or not...
Kurt?
dave
=========================================================================
From: John Levreault <jlevro@mediaone.net>
Subject: Re: [JN] Gap size...
Date: Fri, 24 Mar 2000 15:29:54 -0500
Source: Sound Digest Archive v02.n494
dave slagle wrote:
>
> Just a clarification...
>
> I took kurts comments as to suggesting using small airgaps as opposed to
> big ones...
>
> JL's bringing up partridge... made me realize that may not be what kurt meant...
>
> rather that all trannies should have a gap whether they carry DC or not...
That's what I was referring to, Partridge's use of small airgaps in PP
trannies.
JL
>
> Kurt?
>
> dave
=========================================================================
From: Kurt Steffensen <kurt-steffensen@teliamail.dk>
Subject: Re: [JN] gap size...
Date: Fri, 24 Mar 2000 20:19:59 +0300
Source: Sound Digest Archive v02.n495
John Levreault wrote:
> dave slagle wrote:
> >
> > Kurt
> >
> > can you point me to some reference on this???
> >
> > or try to explain the logic behind it?
>
> I think this idea goes back to Partridge, who still use it even on PP
> iron.
>
> JL
>
I have known about this for so many years , that I have all forgotten about the
sources.
Isn't it in the old books ?
Until I got on the internet , I believed it was common knowledge. At least all the old
winders I have talked to , knew all about it.
An old , unfortunately passed "wizard" , that I have learn many things from , once
showed it to me on a particular high quality audio transformer.
I could not see a thing with the eye , but through a magnifier I just barely spotted
the gap.
I can't remember what material used , but I remember he had some that looked like rice
paper. Paper is used frequently to make the air gap.
The air gap is used to linearise the frequency response of the transformer.
The thump rule is that the air gap should be 1/1000 of the magnetic path. But best
results are found by experiments.
All transformer companies I have been involved with , uses the air gap also on PP
transformers.
And I have myself used it on all the audio transformers I have made.
I do not know if Partridge was the first to use it , but I doubt.
I have read articles from the 1930's discussing this technique.
I do not know if other methods are used instead of the air gap. But I know it is one
of the well known tools in high quality audio transformers.
I remember while reading about it in the past , I considered it similar to the
feedback mechanism , though no feedback actually takes place.
Is this of any help ?
- - Kurt
=========================================================================
From: Kurt Steffensen <kurt-steffensen@teliamail.dk>
Subject: Re: [JN] Gap size...
Date: Sat, 25 Mar 2000 00:08:25 +0300
Source: Sound Digest Archive v02.n495
dave slagle wrote:
> Just a clarification...
>
> I took kurts comments as to suggesting using small airgaps as opposed to
> big ones...
>
> JL's bringing up partridge... made me realize that may not be what kurt meant...
>
> rather that all trannies should have a gap whether they carry DC or not...
>
> Kurt?
Yes , that 's what I meant. Please , see my other post about it.
- - Kurt
>
>
> dave
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: [JN] Garage Machinists
Date: Fri, 31 Mar 2000 16:51:25 -0700 (MST)
Source: Sound Digest Archive v02.n507
Anyone see Michael Fremer's latest in the April Stereophile? Pictures of
several no-compromise turntables. What caught my eye is their
styling. Back in the fifties Fairchild produced a Raymond Loewy-designed
turntable. Despite its sleek beauty, it bellied up.
These modern contraptions flaunt their mechanicalness. They look like the
backyard creations of the village genius/tinkerer, triumphantly
so. Against all trends, these turntables are turned inside out. Look at
me! Look at how I work! Look how substantial and yet ingenious are my
workings!
Darth Vader styling. Geek toys.
Doug Purl
=========================================================================
From: "Jon Lane" <jhlane@email.msn.com>
Subject: RE: [JN] Garage Machinists
Date: Fri, 31 Mar 2000 18:45:26 -0700
Source: Sound Digest Archive v02.n507
> Anyone see Michael Fremer's latest in the April
> Stereophile? Pictures of
> several no-compromise turntables. What caught my
> eye is their
> styling. Back in the fifties Fairchild produced
> a Raymond Loewy-designed
> turntable. Despite its sleek beauty, it bellied up.
>
> These modern contraptions flaunt their
> mechanicalness. They look like the
> backyard creations of the village
> genius/tinkerer, triumphantly
> so. Against all trends, these turntables are
> turned inside out. Look at
> me! Look at how I work! Look how substantial
> and yet ingenious are my
> workings!
>
> Darth Vader styling. Geek toys.
>
> Doug Purl
Thanks for the heads-up.
And on that note, have you seen these:
http://www.geocities.com/Hollywood/Hills/4133/tera_proto1.jp
g
http://www.geocities.com/Hollywood/Hills/4133/tera_proto2.jp
g
http://www.geocities.com/Hollywood/Hills/4133/tera_proto3.jp
g
Jon Lane
=========================================================================
From: Richard C Nevill <rnevill@is.dal.ca>
Subject: Re: [JN] Garage Machinists
Date: Sat, 1 Apr 2000 12:41:16 -0400 (AST)
Source: Sound Digest Archive v02.n507
Yup, saw it.
I think the point to these tt's is that people seem to like the
industrial look of them. When you spend that much money on these things
you might want to show of the machining and fit and finish and such. Look
how popular the SE version of the Gyrodec is.
Personally I prefer the workings boxed in is some nice wood. I replaced
the black industrial looking plinth on my Rega 3 with a nice hunk of oiled
golden oak. Sure looks better and I didn't notice any change in sound.
After all we have to live with these things, there is no reason why they
can't look good as well as function.
Cheers
Richard Nevill
On Fri, 31 Mar 2000, Douglas Purl wrote:
> Anyone see Michael Fremer's latest in the April Stereophile? Pictures of
> several no-compromise turntables. What caught my eye is their
> styling. Back in the fifties Fairchild produced a Raymond Loewy-designed
> turntable. Despite its sleek beauty, it bellied up.
>
> These modern contraptions flaunt their mechanicalness.. They look like the
> backyard creations of the village genius/tinkerer, triumphantly
> so. Against all trends, these turntables are turned inside out. Look at
> me! Look at how I work! Look how substantial and yet ingenious are my
> workings!
>
> Darth Vader styling. Geek toys.
>
> Doug Purl
>
>
=========================================================================
From: Douglas Purl <dcp@selway.umt.edu>
Subject: Re: [JN] Garage Machinists
Date: Sat, 1 Apr 2000 18:09:20 -0700 (MST)
Source: Sound Digest Archive v02.n507
On Sat, 1 Apr 2000, Richard C Nevill wrote:
> I think the point to these tt's is that people seem to like the
> industrial look of them. When you spend that much money on these things
> you might want to show of the machining and fit and finish and such. Look
> how popular the SE version of the Gyrodec is.
The ontological question I do not have an answer for is do these
turntables look techy, like the chandelier that visits Wyoming in _Close
Encounters of the Third Kind_ because they have trained consumers to look
for such styling or are they responding to what they perceive as target
taste?
> Personally I prefer the workings boxed in is some nice wood. I replaced
> the black industrial looking plinth on my Rega 3 with a nice hunk of oiled
> golden oak. Sure looks better and I didn't notice any change in sound.
> After all we have to live with these things, there is no reason why they
> can't look good as well as function.
Long ago, when I was seized with delusions of grandeur, my impulse was to
minimize, streamline, simplify, and thereby render elegant and truthful
our design. I believed that arm design was still contaminated by radio
station practice where massive metal arms carried big honkers of
cartridges. They looked too much like old transcription arms that also
carried cutters. The Weathers FM pickup system, turntable and arm and
cartridge, had influenced me. As a tackle I knew that I had to catch a
running back within ten yards or I would become a spectator. He was built
for his purpose and I for mine.
Many of the tonearm compensators on these arms derive from a
misunderstanding of the forces involved. They are built to compensate for
dynamic forces that simply do not occur in tonearms. It is flat
unnecessary to annul dynamic forces in every plane. But such gee-gaws are
impressive to look at.
In a word, I am wondering aloud if these expensive turntable/arm combos
are built for sight more than sound.
All the more reason for the dumpster rats here to design and fabricate
their own turntable -- and arm. Repeat after me: tone arms need not be
made of metal.
Doug Purl
=========================================================================
From: "Joseph Robertson" <joerbus@mindspring.com>
Subject: Re: [JN] Garage Machinists
Date: Sat, 1 Apr 2000 21:40:06 -0500
Source: Sound Digest Archive v02.n507
- ----- Original Message -----
From: Douglas Purl <dcp@selway.umt.edu>
To: <sound@deliverator.io.com>
Sent: Saturday, April 01, 2000 8:09 PM
Subject: Re: [JN] Garage Machinists
Additional few cents worth at bottom-
> On Sat, 1 Apr 2000, Richard C Nevill wrote:
>
>Snip-snippity-doodah-
>
> The ontological question I do not have an answer for is do these
> turntables look techy, like the chandelier that visits Wyoming in _Close
> Encounters of the Third Kind_ because they have trained consumers to look
> for such styling or are they responding to what they perceive as target
> taste?
Snip-snippity-day-
>
>
> Long ago, when I was seized with delusions of grandeur, my impulse was to
> minimize, streamline, simplify, and thereby render elegant and truthful
> our design. I believed that arm design was still contaminated by radio
> station practice where massive metal arms carried big honkers of
> cartridges. They looked too much like old transcription arms that also
> carried cutters. The Weathers FM pickup system, turntable and arm and
> cartridge, had influenced me. As a tackle I knew that I had to catch a
> running back within ten yards or I would become a spectator. He was built
> for his purpose and I for mine.
>
> One last snip-
>
> In a word, I am wondering aloud if these expensive turntable/arm combos
> are built for sight more than sound.
>
> All the more reason for the dumpster rats here to design and fabricate
> their own turntable -- and arm. Repeat after me: tone arms need not be
> made of metal.
Doug Purl
Speaking of non- metal arms,there was a 16"wooden truss-like arm with
carbon fiber mounting plates built by one of the Bottleheads in Seattle
(fill us in,Doc)
Several people(including myself)commented on how it reminded them of the old
Third Street bridge in San Francisco.At any rate,what a refreshing change
from the Hi-Tech-Das-Machina look so prevalent these days.
Joe Robertson
>
>
>
>
>
=========================================================================
From: "gtrmkr" <gtrmkr@wans.net>
Subject: Re: [JN] Garage Machinists
Date: Sat, 1 Apr 2000 22:06:55 -0500
Source: Sound Digest Archive v02.n507
Doug wrote (snipped):
> All the more reason for the dumpster rats here to design and fabricate
> their own turntable -- and arm. Repeat after me: tone arms need not be
> made of metal.
When I was a teenager I fooled around with trying to build a tone arm. I
also built flyrods from Tonken cane (bamboo) and graphite (still do
occasionally).
The one I actually got to work was made from tempered cane, tapered
octagonal cross section. Epoxied one of those tiny B&O cartridges right to
the end of it. Adjusted the overhang by sliding the whole arm through a hole
in a small block of ebony (secured with a set screw) which in tune was
suspended by a short piece of .009 guitar string running through it for the
vertical axis "bearing." The pivot bearing was a problem--wound up using a
short piece of brass rod sunk into the ebony block, with that riding in an
oil-impregnated silicon bronze bushing. I just epoxied the bushing to a
small piece of maple, which was the mounting board. Counter weights were
fishing sinkers. No VTA or anti-skate provisions.
Mounted it in on an old Phillips belt drive table.
It sounded terrible, but I thought is was great. The cartridge wires weighed
more than the bamboo arm!
Always thought I'd try something like that again someday...
Later,
Jim
=========================================================================
From: "Dale Simon-contr" <Dale.Simon-contr@trw.com>
Subject: [JN] garage rock
Date: Fri, 03 Aug 2001 12:49:19 -0400
Source: Sound Digest Archive v02.n939
I recently downloaded Ken's mp3s from the sound server. Very cool Ken, thanks. Anyone else done an
y cool recordings they would like to share?
Dale
=========================================================================
From: Robert Root <rrjlife@earthlink.net>
Subject: [JN] Garage Sale:
Date: Tue, 23 Mar 1999 08:23:27 -0800
Source: Sound Digest Archive v02.n088
WE-102D Tennis $350/pr
KR-2A3 Flat Plate NIB Matched $350/pr
KR-300BXLS NIB Matched $395/pr
Mega-Hertz Line Outputs $.3K/600ohms 30ma for Euridice $250/pr
TFA 2004-Pinstripe Permalloy-brass bell ends NIB $500/pr
Tango NY-15 NIB $850/pr
Tamura 7003 Permalloy NIB $600/pr
TV-7-D/U Tester $250
=========================================================================
From: Robert Root <rrjlife@earthlink.net>
Subject: [JN] Garage Sale:
Date: Sat, 10 Apr 1999 10:27:39 -0700
Source: Sound Digest Archive v02.n119
- --Altec 805B Horns Gd.Cond $525/pr + ship
- --Altec 288K Drivers Vry.Gd.Cond. $525/pr +ship
- --Altec 515E Gd.Cond Orig. cones $425/pr +ship
- --KR300BXLS NIB-Matched $350/pr
- --KR-283 Flat NIB-Matched $350/pr
- --TFA 2004-Pinstripe Permalloy-Brass Bell Ends NIB $495/pr
- --TV-7-D/U Tester $250
- --Orig ST-70 GD.Cond-no rust/mint cage $250
Wanted: Amperex 211's
=========================================================================
From: Jeff Mai <j.mai.lists@home.com>
Subject: [JN] Garage Sale
Date: Sat, 14 Jul 2001 22:40:16 -0600
Source: Sound Digest Archive v02.n925
I'm moving to a new apartment in August. In four months I'll be
moving to Australia for at least two years and I can only take a
minimum of tube stuff along (shipping everything is not an option; I
have too many CDs to ship as it is.)
So, here's a bunch of stuff that I'd like to get rid of. Some of
it's fairly decent stuff; some of it's junk. There's enough here to
build a modest SE amp if you add a chassis, hardware and some
resistors. Some of the stuff is worthless, but I'd sooner someone
else use it if they can than litter a landfill with it.
I've got stuff divided up into lots, but if you want to separate
things let me know. Or even better, we can put things together;
offers or trades for many lots or all of the stuff together will be
considered first ($450 anyone?) I'll wait until this coming Tuesday
evening for offers on the entire lot (or many of them, anyway.)
After that, trades and offers considered on individual items, too.
I can use valve and transformer books and print articles I don't
already have. Also, an extensive archive of Joe-list posts prior to
what's currently archived at io.com is valuable to me. If you want
to use this for barter, let me know what you've got (date range, # of
articles, etc.) A complete archive back to the first Joe-list post
would be worth as much as $100 to me; check to see what you have.
Any item left over that isn't worth the effort of listing on eBay
will be put in the dumpster. Anything $5 or less is fair game to
throw in free with other more expensive lots. I'll be most likely to
wheel and deal if you want many lots.
Links to photos of each lot are provided in the list below. All of
the prices *do not* include shipping.
Lot #1: http://members.home.com/j.mai.lists/garagesale/101-0101_IMG.JPG
Magnetic Circuits and Transformers, MIT. Extensive highlighting in
pencil. 2 inch split on spine, some tape used to index pages. All
pages are legible and held fast in binding. Good book, only selling
because it's a duplicate. $30
Lot #2: http://members.home.com/j.mai.lists/garagesale/101-0102_IMG.JPG
Large, vintage Hammond plate transformer. Type 720X60 , 250 VA.
Current model 720 is 1250 VCT @ 300ma, but this would exceed the
250VA rating. It's exactly the same core size as that model, though.
Way cool name plate, but some rust. With a little refinishing this
would look really trick. $30
Lot #3: http://members.home.com/j.mai.lists/garagesale/101-0103_IMG.JPG
Big Freed Choke. 2.5 HY, 700ma, 43V RMS, 23 ohms, 1000V WV. Cap
input only, I'm guessing from the RMS rating. $15
Lot #4: http://members.home.com/j.mai.lists/garagesale/101-0104_IMG.JPG
Another Big Freed Choke. 1.8 HY, 700ma, 500V RMS, 11 ohms! 1600V WV. $15
Lot #5: http://members.home.com/j.mai.lists/garagesale/101-0105_IMG.JPG
Dual choke. 2 * 4 HY, 120 ma, 150V RMS, 47 ohms, 300V WV. $15
Lot #6: http://members.home.com/j.mai.lists/garagesale/101-0106_IMG.JPG
Monster home brew aircore coils. A lot of freakin' work! Between 6
and 7 mH (I never measured them), 12 ga wire. Low DCR. $15 the pair
Lot #7: http://members.home.com/j.mai.lists/garagesale/101-0107_IMG.JPG
Two RS soldering irons. 40 Watt and 25 Watt. $5
Lot #8: http://members.home.com/j.mai.lists/garagesale/101-0108_IMG.JPG
Half assed attempt at SS power supply. Unfinished. You can only
have this if you promise not to laugh at my primitive soldering job.
Probably what's good here are the 8 Panasonic TSW 10000uF, 35V caps.
There are two pieces each LT1085 and LT1033 regs, but I don't know if
they're good. $5
Lot #9: http://members.home.com/j.mai.lists/garagesale/101-0109_IMG.JPG
RCA cables. 5 stereo pairs. Cheap stuff except for one Monster
Cable pair (which was still cheap, just not as cheap.) $5
Lot #10: http://members.home.com/j.mai.lists/garagesale/101-0110_IMG.JPG
Microphone. Stereo miniplug. Ultra cheap; came with computer. I'll
throw it in with something else if you want it.
Lot #11: http://members.home.com/j.mai.lists/garagesale/101-0111_IMG.JPG
A lot of terminated coaxial video cable. One S-VHS cable. $5
Lot #12: http://members.home.com/j.mai.lists/garagesale/101-0112_IMG.JPG
Cheap plastic project box. Knobs, pots, RCA jacks. Free with purchase!
Lot #13: http://members.home.com/j.mai.lists/garagesale/101-0113_IMG.JPG
Wall wart. 14 VDC @ 850 ma. $5
Lot #14: http://members.home.com/j.mai.lists/garagesale/101-0114_IMG.JPG
Big pile 'o caps. Except for the two Techtronix branded caps at
left, they're pretty much all electrolytics. Most of them are NOS
low voltage. $10
Lot #15: http://members.home.com/j.mai.lists/garagesale/101-0115_IMG.JPG
Odd tube sockets. A nine pin mini Vector socket and two 7 pin mini
adapters with test points. Freebie with other stuff.
Lot #16: http://members.home.com/j.mai.lists/garagesale/101-0116_IMG.JPG
http://members.home.com/j.mai.lists/garagesale/101-0117_IMG.JPG
NIB Peerless IT. PP - PP, 20K - 30K. Model G-336-A. Don't know if
this is worth anything, but it's a nice looking little tranny. Cool
box. $20
Skip Lot #17 to preserve synchronicity with image numbers
Lot #18: http://members.home.com/j.mai.lists/garagesale/101-0118_IMG.JPG
Misc unknown transformers. Two in front are fil trans I bought for
6B4Gs. They are either 12.6VCT @ 0.6 amp or 6.3VCT @ 1.2 amp. The
others are unmarked and unknown. $10
Lot #19: http://members.home.com/j.mai.lists/garagesale/101-0119_IMG.JPG
Pair UTC 20VCT fil trans. $10
Lot #20: http://members.home.com/j.mai.lists/garagesale/101-0120_IMG.JPG
Smaller homebrew aircore coils. Between 1 and 2 mH. 12 ga. Low DCR. $7
Lot #21: http://members.home.com/j.mai.lists/garagesale/101-0121_IMG.JPG
Unknown chokes. $5
Lot #22: http://members.home.com/j.mai.lists/garagesale/101-0122_IMG.JPG
NOS Thordarson Fil Trans. 6.3VCT @ 0.6 amps. $5
Lot #23: http://members.home.com/j.mai.lists/garagesale/101-0123_IMG.JPG
15 UX5 sockets. Some nice ceramic ones. $15
Lot #24: http://members.home.com/j.mai.lists/garagesale/101-0124_IMG.JPG
Pair new 9 pin Ceramic Magnoval sockets. For 6D22S, I think. $5
Lot #25: http://members.home.com/j.mai.lists/garagesale/101-0125_IMG.JPG
16 - 0.05uF + 0.05uF 1000VDC Aerovox caps. Oil, I think. Parallel
sections for low value coupling cap. $5
Lot #26: http://members.home.com/j.mai.lists/garagesale/101-0126_IMG.JPG
5 GE Pyranol (PCB) Oil caps. 600 VDC. 4 * 2uF, 1 * 10uF. Free
because of disposal hassles.
Lot #27: http://members.home.com/j.mai.lists/garagesale/101-0127_IMG.JPG
5 No PCB Oil caps. 2 * 20uF @ 330VAC, 2 * 40uf + 4uF @ 370 VAC, 1 *
4uF @ 370V. $15
Lot #28: http://members.home.com/j.mai.lists/garagesale/101-0128_IMG.JPG
NIB high voltage oil cap. 12uF @ 660VAC. No PCB. $7
Lot #29: http://members.home.com/j.mai.lists/garagesale/101-0129_IMG.JPG
Surgistor? Unknown pot with switch. 100 ohm 10 turn WW pot. Misc
ICs. Throw in.
Lot #30: http://members.home.com/j.mai.lists/garagesale/101-0130_IMG.JPG
Big unknown plate and fil trans. It's the same size as the Hammond
above. I measured it once upon a time and it was well over 1000VCT
with no load. $20
Lot #31: http://members.home.com/j.mai.lists/garagesale/101-0131_IMG.JPG
Avel Toroid. 18V + 18V. Dual 120V primaries. Model D4030. $15
Lot #32: http://members.home.com/j.mai.lists/garagesale/101-0132_IMG.JPG
Pair Triad Universal OPTs. 12 Watts. Small. No connection diagram
or specs. I got these once upon a time from Ed Bilecci. He may have
more info. $15
Lot #33: http://members.home.com/j.mai.lists/garagesale/101-0133_IMG.JPG
Unknown trans. Decent sized. I'll include with lot #18.
Lot #34: http://members.home.com/j.mai.lists/garagesale/101-0134_IMG.JPG
Pair mil surplus plate and fil trans. 720VCT @ 125 ma, 6.3VAC @
3.5A, 6.3VAC @ 2A. Dual 115V primaries. Two terminals were broken
off one unit. I repaired with wire. Work fine. Great for monoblock
amps. $30
Lot #35: http://members.home.com/j.mai.lists/garagesale/101-0135_IMG.JPG
Huge WE 354A MV rectifier. Base loose. I doubt it works but don't
know for sure. Free.
Lot #36: http://members.home.com/j.mai.lists/garagesale/101-0136_IMG.JPG
Delco 50 tube. Looks and tests as new. Let's call it lightly used. $100
Lot #37: http://members.home.com/j.mai.lists/garagesale/101-0137_IMG.JPG
Pair NOS Philco 6B4G, white boxes. $50
Lot #38: http://members.home.com/j.mai.lists/garagesale/101-0138_IMG.JPG
Pair NIB Valve Art 2A3. $30
Lot #39: http://members.home.com/j.mai.lists/garagesale/101-0139_IMG.JPG
Sylvania 83 MV rectifier, used. $7
Lot #40: http://members.home.com/j.mai.lists/garagesale/101-0140_IMG.JPG
NIB Cetron 323B MV thyratron. $5
Lot #41: http://members.home.com/j.mai.lists/garagesale/101-0141_IMG.JPG
Pair RCA 80 rectifiers. Used. One boxed. $12
Lot #42: http://members.home.com/j.mai.lists/garagesale/101-0142_IMG.JPG
Misc tubes. 3 * NEC 6AR5, NEC 12AT7, NEC 6CA4, all pulls. 6D6,
6DM4, 2X2, 2C53, 2 * 6F4. $5
Lot #43: http://members.home.com/j.mai.lists/garagesale/101-0143_IMG.JPG
15 NOS JAN 6688 pentodes. Good drivers for power triodes. $3 each
Lot #44: http://members.home.com/j.mai.lists/garagesale/101-0144_IMG.JPG
Philips 5U4GB, used. $5
Lot #45: http://members.home.com/j.mai.lists/garagesale/101-0145_IMG.JPG
4 NOS Tung-Sol 6AX5GT. Nice little rectifiers with 6.3VAC fils. $10
Lot #46: http://members.home.com/j.mai.lists/garagesale/101-0146_IMG.JPG
10 Misc 6AC7. Mostly GE and Ken-Rad despite what the boxes say.
Some rattle a bit. No way to test. I'll guarantee 4 are good
(unless I wind up giving them away, of course.) $7
Lot #47: http://members.home.com/j.mai.lists/garagesale/101-0147_IMG.JPG
Tung-Sol 50, Globe. Filament tests open! Could be loose in base.
Sorta like a lottery ticket. Nice display tube anyway. $5
Lot #48: http://members.home.com/j.mai.lists/garagesale/101-0148_IMG.JPG
2 NOS 12AX7. Stinky boxes. $10
Thanks for the bandwidth.
Jeff
=========================================================================
From: "Mackris, Thom G." <tgmackris@vicorpinc.com>
Subject: [JN] Garage Sale - Ariel Drivers
Date: Tue, 7 Dec 1999 11:39:58 -0700
Source: Sound Digest Archive v02.n356
Too much on my plate at the moment & I need to fund some other projects
(Scheu turntable, CD mods, a Darling), so ...
I have:
o 4 *brand new* Vifa P13WH-00-08 drivers (purchased from NorthCreek in the
Spring of '97)
o 2 *used* Scan Speak D2905/9300 tweeters
The Vifas have been sitting in their packing, waiting for me to get off my
arse to build a pair of Ariels. I have not even tested them, although I
will run an amp through them prior to shipping.
The ScanSpeaks had been living in a pair of standard cones & domes speakers
from about 1991 until last year (1998) when I got my Lowthers up and
running.
I'd like to sell the package for the price that I paid for the Vifa's ($140)
plus shipping.
Thanks,
Thom
=========================================================================
From: "Mackris, Thom G." <tgmackris@vicorpinc.com>
Subject: Re: [JN] Garage Sale - Ariel Drivers
Date: Wed, 8 Dec 1999 13:29:01 -0700
Source: Sound Digest Archive v02.n358
Hi all,
The drivers are sold. Thanks for your interest.
Thom
=========================================================================
From: "Ed Coleman" <ecoleman@whidbey.net>
Subject: [JN] Garage sale , Books ,books and more books
Date: Mon, 9 Oct 2000 20:10:53 -0700
Source: Sound Digest Archive v02.n689
This is a multi-part message in MIME format.
- ------=_NextPart_000_000A_01C0322D.069F6380
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
"Hi Joes, I 'm clearing out a sh*t load of books ,if you're =
interested,contact me off list and make a reasonable offer (+postage ) =
TIA Ed
Qualitative Analysis and Electrolytic Solutions" by Edward J. King; =
"Fundamentals of Vacuum Tubes," by Eastman, 2nd Ed.; "Industrial =
Electronic Control: A Guide to the Understanding of Electronic Control =
Circuits for Industrial Use" by Cockrell, 1st Ed.; "G.E. Transistor =
Manual" 6th Ed.; "Electrical Fundamentals of Communication" by Arthur =
Albert, 1st ed.; "Practical Handbook of Solid State Troubleshooting" by =
Robert Glenn; "Fundamentals of Single Side Band" Navy Dept., Bureau of =
Ships; "Rules and Regulations" Federal Communication Commission, Vol 6, =
January 1972; "Automatic Data Processing Glossary" Dept of Command =
Communications, Army Signal School; "Automatic Data Processing Glossary" =
Executive Office of the President, Bureau of the Budget; "Fundamentals =
of Radio Telemetry" Marvin Tepper; "Radio Handbook" 9th Ed. 1942; =
"Principals of Television Engineering" Donald Fink, 1st. ed. 1940; =
"Electrical Engineering Circuits" 2nd Ed. Hugh Skilling; "Electronics =
Engineering Manual, Revised Edition" ; "Principals of Radio" 6th Ed. =
Henney and Richardson, 1955; "Ultra-high Frequency Techniques " by =
Brainerd, Koehler, Reich, and Woodruff, 17th Ed. 1942; "Telephone Theory =
and Practice: Automatic Switching and Auxiliary Equipment" by Miller, =
1st Ed. 1933; "Radio Operating Questions and Answers" by Nilson and =
Hornung, 5th ed. 1933; "Fundamentals of Telephony" by Albert, 1st Ed.; =
"Microwave Transmission" by Slater, 1st Ed. 1942; "Radio Frequency =
Measurements by Bridge and Resonance Methods" by Hartshorn, 1940; "Radio =
Telegraphy and Telephony" by Duncan and Drew, 2nd ed. 1931; "Principals =
of Aeronautical Radio Engineering" by Sandretto, 1st ed. 1942; "Acoustic =
Measurements" by Beranek, 1949; "Radio Regulations" Geneva 1959; =
"Communication Engineering" by Everitt, 2nd Ed. 1937; "Radio =
Meteorology" by Bean and Dutton 1966; "Telephone Central Office" by =
Freedman 1939; "Radio Engineering Handbook" 1942 Henney; "Special Power =
Supplies for Radio Equipment" National Radio Institute, 1940; =
"Principals of Radar" MIT Radar School, 1946; "Electrons at Work" by =
Underhill, 1933; "Radiotron Designer's Handbook," 3rd Ed. 1941; =
"Reference Data for Radio Engineers" 1946; "Federal Telephone and Radio" =
1946; "Digital Logic Handbook-Flip Chip Modules" 1967; "Understanding =
Solid State Electronics" 3rdEd., Radio Shack;"Principals of Electricity =
Applied to Telephone and Telegraph Work" 1953; "Semi-conductor Reference =
Guide"1985; "Essential Characteristics Principals, Ratings, Electrical =
and Physical Characteristics" 10th ed., GE; "The Technical Report - Its' =
preparation, processing and use in industry and government" 1954; =
"Electrical Communication" by Albert 1940; "Installation and Maintenance =
of Electrical Supply and Communication Lines" 1949, U.S. Govt.; =
"Electrical Engineers Handbook - Electric Communication and Electronics" =
by Pender & McIlwain, 4th ed. 1950; "Rodget's Dictionary of Electrical =
Terms" 3rd Ed. 1938; "Preparation of Engineering Reports" Agg & Foster, =
1st Ed. 1935; "Telephone Theory and Practice" Miller 1st Ed. 1933; =
"Aircraft Radio and Electrical Equipment" by Morgan 1939; "Radiotron =
Designer's Handbook" 3rd ed., 1941; "Principals of Electricity Applied =
to Telephone and Telegraph Work" 1929 AT&T; "The Computer Revolution" by =
Berkeley, 1962; "Mathematics for Self Study" Thompson, 14th printing, =
1931; "How to Pass Radio License Examinations" 1952; "Radio Engineering" =
Terman 3rd ed., 1947; "Measurements in Radio Engineering" by Terman 1st =
ed. 10th impression, 1935; "Measurements in Radio Engineering" by Terman =
1st ed. 4th impression, 1935; "Amateur Single Side Band" Collins Radio =
Co. 1962; "Radio Amateur's Handbook" 21st Ed. 1944 American Radio Relay =
League; "Radio Amateurs Handbook" 1968 American Radio Relay League; =
"Radio Amateur's License Manual" 35th ed. ;"Relay Engineering" by =
Packard 1st ed. 1945.
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<HTML>
<HEAD>
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<DIV><FONT color=3D#000000 size=3D2>"Hi Joes, I 'm clearing out a =
sh*t load of=20
books ,if you're interested,contact me off list and make a reasonable =
offer=20
(+postage ) TIA Ed</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2> Qualitative Analysis and =
Electrolytic=20
Solutions" by Edward J. King; "Fundamentals of Vacuum =
Tubes," by=20
Eastman, 2nd Ed.; "Industrial Electronic Control: A Guide to the=20
Understanding of Electronic Control Circuits for Industrial Use" by =
Cockrell, 1st Ed.; "G.E. Transistor Manual" 6th Ed.; =
"Electrical=20
Fundamentals of Communication" by Arthur Albert, 1st ed.; =
"Practical=20
Handbook of Solid State Troubleshooting" by Robert Glenn;=20
"Fundamentals of Single Side Band" Navy Dept., Bureau of =
Ships;=20
"Rules and Regulations" Federal Communication Commission, Vol =
6,=20
January 1972; "Automatic Data Processing Glossary" Dept of =
Command=20
Communications, Army Signal School; "Automatic Data Processing=20
Glossary" Executive Office of the President, Bureau of the Budget;=20
"Fundamentals of Radio Telemetry" Marvin Tepper; "Radio=20
Handbook" 9th Ed. 1942; "Principals of Television =
Engineering"=20
Donald Fink, 1st. ed. 1940; "Electrical Engineering Circuits" =
2nd Ed.=20
Hugh Skilling; "Electronics Engineering Manual, Revised =
Edition" ;=20
"Principals of Radio" 6th Ed. Henney and Richardson, 1955;=20
"Ultra-high Frequency Techniques " by Brainerd, Koehler, =
Reich, and=20
Woodruff, 17th Ed. 1942; "Telephone Theory and Practice: Automatic=20
Switching and Auxiliary Equipment" by Miller, 1st Ed. 1933; =
"Radio=20
Operating Questions and Answers" by Nilson and Hornung, 5th ed. =
1933;=20
"Fundamentals of Telephony" by Albert, 1st Ed.; =
"Microwave=20
Transmission" by Slater, 1st Ed. 1942; "Radio Frequency =
Measurements=20
by Bridge and Resonance Methods" by Hartshorn, 1940; "Radio =
Telegraphy=20
and Telephony" by Duncan and Drew, 2nd ed. 1931; "Principals =
of=20
Aeronautical Radio Engineering" by Sandretto, 1st ed. 1942; =
"Acoustic=20
Measurements" by Beranek, 1949; "Radio Regulations" =
Geneva 1959;=20
"Communication Engineering" by Everitt, 2nd Ed. 1937; =
"Radio=20
Meteorology" by Bean and Dutton 1966; "Telephone Central =
Office"=20
by Freedman 1939; "Radio Engineering Handbook" 1942 Henney;=20
"Special Power Supplies for Radio Equipment" National Radio =
Institute,=20
1940; "Principals of Radar" MIT Radar School, 1946; =
"Electrons at=20
Work" by Underhill, 1933; "Radiotron Designer's =
Handbook," 3rd=20
Ed. 1941; "Reference Data for Radio Engineers" 1946; =
"Federal=20
Telephone and Radio" 1946; "Digital Logic Handbook-Flip Chip=20
Modules" 1967; "Understanding Solid State Electronics" =
3rdEd.,=20
Radio Shack;"Principals of Electricity Applied to Telephone and =
Telegraph=20
Work" 1953; "Semi-conductor Reference Guide"1985; =
"Essential=20
Characteristics Principals, Ratings, Electrical and Physical=20
Characteristics" 10th ed., GE; "The Technical Report - Its'=20
preparation, processing and use in industry and government" 1954;=20
"Electrical Communication" by Albert 1940; "Installation =
and=20
Maintenance of Electrical Supply and Communication Lines" 1949, =
U.S. Govt.;=20
"Electrical Engineers Handbook - Electric Communication and=20
Electronics" by Pender & McIlwain, 4th ed. 1950; "Rodget's =
Dictionary of Electrical Terms" 3rd Ed. 1938; "Preparation of=20
Engineering Reports" Agg & Foster, 1st Ed. 1935; =
"Telephone Theory=20
and Practice" Miller 1st Ed. 1933; "Aircraft Radio and =
Electrical=20
Equipment" by Morgan 1939; "Radiotron Designer's =
Handbook" 3rd=20
ed., 1941; "Principals of Electricity Applied to Telephone and =
Telegraph=20
Work" 1929 AT&T; "The Computer Revolution" by =
Berkeley, 1962;=20
"Mathematics for Self Study" Thompson, 14th printing, 1931; =
"How=20
to Pass Radio License Examinations" 1952; "Radio =
Engineering"=20
Terman 3rd ed., 1947; "Measurements in Radio Engineering" by =
Terman=20
1st ed. 10th impression, 1935; "Measurements in Radio =
Engineering" by=20
Terman 1st ed. 4th impression, 1935; "Amateur Single Side =
Band"=20
Collins Radio Co. 1962; "Radio Amateur's Handbook" 21st Ed. =
1944=20
American Radio Relay League; "Radio Amateurs Handbook" 1968 =
American=20
Radio Relay League; "Radio Amateur's License Manual" 35th ed.=20
;"Relay Engineering" by Packard 1st ed.=20
1945.<BR></FONT></DIV></BODY></HTML>
- ------=_NextPart_000_000A_01C0322D.069F6380--
=========================================================================
From: "Ed Coleman" <ecoleman@whidbey.net>
Subject: [JN] Garage sale ,books ,books and more books!
Date: Mon, 9 Oct 2000 20:20:16 -0700
Source: Sound Digest Archive v02.n690
This is a multi-part message in MIME format.
- ------=_NextPart_000_0067_01C0322E.567B9D00
Content-Type: text/plain;
charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
"Hi Joes, I 'm clearing out a sh*t load of books ,if you're =
interested,contact me off list and make a reasonable offer (+postage ) =
TIA Ed
=20
Qualitative Analysis and Electrolytic Solutions" by Edward J. King; =
"Fundamentals of Vacuum Tubes," by Eastman, 2nd Ed.; "Industrial =
Electronic Control: A Guide to the Understanding of Electronic Control =
Circuits for Industrial Use" by Cockrell, 1st Ed.; "G.E. Transistor =
Manual" 6th Ed.; "Electrical Fundamentals of Communication" by Arthur =
Albert, 1st ed.; "Practical Handbook of Solid State Troubleshooting" by =
Robert Glenn; "Fundamentals of Single Side Band" Navy Dept., Bureau of =
Ships; "Rules and Regulations" Federal Communication Commission, Vol 6, =
January 1972; "Automatic Data Processing Glossary" Dept of Command =
Communications, Army Signal School; "Automatic Data Processing Glossary" =
Executive Office of the President, Bureau of the Budget; "Fundamentals =
of Radio Telemetry" Marvin Tepper; "Radio Handbook" 9th Ed. 1942; =
"Principals of Television Engineering" Donald Fink, 1st. ed. 1940; =
"Electrical Engineering Circuits" 2nd Ed. Hugh Skilling; "Electronics =
Engineering Manual, Revised Edition" ; "Principals of Radio" 6th Ed. =
Henney and Richardson, 1955; "Ultra-high Frequency Techniques " by =
Brainerd, Koehler, Reich, and Woodruff, 17th Ed. 1942; "Telephone Theory =
and Practice: Automatic Switching and Auxiliary Equipment" by Miller, =
1st Ed. 1933; "Radio Operating Questions and Answers" by Nilson and =
Hornung, 5th ed. 1933; "Fundamentals of Telephony" by Albert, 1st Ed.; =
"Microwave Transmission" by Slater, 1st Ed. 1942; "Radio Frequency =
Measurements by Bridge and Resonance Methods" by Hartshorn, 1940; "Radio =
Telegraphy and Telephony" by Duncan and Drew, 2nd ed. 1931; "Principals =
of Aeronautical Radio Engineering" by Sandretto, 1st ed. 1942; "Acoustic =
Measurements" by Beranek, 1949; "Radio Regulations" Geneva 1959; =
"Communication Engineering" by Everitt, 2nd Ed. 1937; "Radio =
Meteorology" by Bean and Dutton 1966; "Telephone Central Office" by =
Freedman 1939; "Radio Engineering Handbook" 1942 Henney; "Special Power =
Supplies for Radio Equipment" National Radio Institute, 1940; =
"Principals of Radar" MIT Radar School, 1946; "Electrons at Work" by =
Underhill, 1933; "Radiotron Designer's Handbook," 3rd Ed. 1941; =
"Reference Data for Radio Engineers" 1946; "Federal Telephone and Radio" =
1946; "Digital Logic Handbook-Flip Chip Modules" 1967; "Understanding =
Solid State Electronics" 3rdEd., Radio Shack;"Principals of Electricity =
Applied to Telephone and Telegraph Work" 1953; "Semi-conductor Reference =
Guide"1985; "Essential Characteristics Principals, Ratings, Electrical =
and Physical Characteristics" 10th ed., GE; "The Technical Report - Its' =
preparation, processing and use in industry and government" 1954; =
"Electrical Communication" by Albert 1940; "Installation and Maintenance =
of Electrical Supply and Communication Lines" 1949, U.S. Govt.; =
"Electrical Engineers Handbook - Electric Communication and Electronics" =
by Pender & McIlwain, 4th ed. 1950; "Rodget's Dictionary of Electrical =
Terms" 3rd Ed. 1938; "Preparation of Engineering Reports" Agg & Foster, =
1st Ed. 1935; "Telephone Theory and Practice" Miller 1st Ed. 1933; =
"Aircraft Radio and Electrical Equipment" by Morgan 1939; "Radiotron =
Designer's Handbook" 3rd ed., 1941; "Principals of Electricity Applied =
to Telephone and Telegraph Work" 1929 AT&T; "The Computer Revolution" by =
Berkeley, 1962; "Mathematics for Self Study" Thompson, 14th printing, =
1931; "How to Pass Radio License Examinations" 1952; "Radio Engineering" =
Terman 3rd ed., 1947; "Measurements in Radio Engineering" by Terman 1st =
ed. 10th impression, 1935; "Measurements in Radio Engineering" by Terman =
1st ed. 4th impression, 1935; "Amateur Single Side Band" Collins Radio =
Co. 1962; "Radio Amateur's Handbook" 21st Ed. 1944 American Radio Relay =
League; "Radio Amateurs Handbook" 1968 American Radio Relay League; =
"Radio Amateur's License Manual" 35th ed. ;"Relay Engineering" by =
Packard 1st ed. 1945.
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charset="iso-8859-1"
Content-Transfer-Encoding: quoted-printable
<!DOCTYPE HTML PUBLIC "-//W3C//DTD W3 HTML//EN">
<HTML>
<HEAD>
<META content=3Dtext/html;charset=3Diso-8859-1 =
http-equiv=3DContent-Type>
<META content=3D'"MSHTML 4.72.3110.7"' name=3DGENERATOR>
</HEAD>
<BODY bgColor=3D#b8b8b8>
<DIV>
<DIV><FONT color=3D#000000 size=3D2>"Hi Joes, I 'm clearing out a =
sh*t load of=20
books ,if you're interested,contact me off list and make a reasonable =
offer=20
(+postage ) TIA Ed</FONT></DIV>
<DIV><FONT color=3D#000000 size=3D2></FONT> </DIV>
<DIV><FONT color=3D#000000 size=3D2> Qualitative Analysis and =
Electrolytic=20
Solutions" by Edward J. King; "Fundamentals of Vacuum =
Tubes," by=20
Eastman, 2nd Ed.; "Industrial Electronic Control: A Guide to the=20
Understanding of Electronic Control Circuits for Industrial Use" by =
Cockrell, 1st Ed.; "G.E. Transistor Manual" 6th Ed.; =
"Electrical=20
Fundamentals of Communication" by Arthur Albert, 1st ed.; =
"Practical=20
Handbook of Solid State Troubleshooting" by Robert Glenn;=20
"Fundamentals of Single Side Band" Navy Dept., Bureau of =
Ships;=20
"Rules and Regulations" Federal Communication Commission, Vol =
6,=20
January 1972; "Automatic Data Processing Glossary" Dept of =
Command=20
Communications, Army Signal School; "Automatic Data Processing=20
Glossary" Executive Office of the President, Bureau of the Budget;=20
"Fundamentals of Radio Telemetry" Marvin Tepper; "Radio=20
Handbook" 9th Ed. 1942; "Principals of Television =
Engineering"=20
Donald Fink, 1st. ed. 1940; "Electrical Engineering Circuits" =
2nd Ed.=20
Hugh Skilling; "Electronics Engineering Manual, Revised =
Edition" ;=20
"Principals of Radio" 6th Ed. Henney and Richardson, 1955;=20
"Ultra-high Frequency Techniques " by Brainerd, Koehler, =
Reich, and=20
Woodruff, 17th Ed. 1942; "Telephone Theory and Practice: Automatic=20
Switching and Auxiliary Equipment" by Miller, 1st Ed. 1933; =
"Radio=20
Operating Questions and Answers" by Nilson and Hornung, 5th ed. =
1933;=20
"Fundamentals of Telephony" by Albert, 1st Ed.; =
"Microwave=20
Transmission" by Slater, 1st Ed. 1942; "Radio Frequency =
Measurements=20
by Bridge and Resonance Methods" by Hartshorn, 1940; "Radio =
Telegraphy=20
and Telephony" by Duncan and Drew, 2nd ed. 1931; "Principals =
of=20
Aeronautical Radio Engineering" by Sandretto, 1st ed. 1942; =
"Acoustic=20
Measurements" by Beranek, 1949; "Radio Regulations" =
Geneva 1959;=20
"Communication Engineering" by Everitt, 2nd Ed. 1937; =
"Radio=20
Meteorology" by Bean and Dutton 1966; "Telephone Central =
Office"=20
by Freedman 1939; "Radio Engineering Handbook" 1942 Henney;=20
"Special Power Supplies for Radio Equipment" National Radio =
Institute,=20
1940; "Principals of Radar" MIT Radar School, 1946; =
"Electrons at=20
Work" by Underhill, 1933; "Radiotron Designer's =
Handbook," 3rd=20
Ed. 1941; "Reference Data for Radio Engineers" 1946; =
"Federal=20
Telephone and Radio" 1946; "Digital Logic Handbook-Flip Chip=20
Modules" 1967; "Understanding Solid State Electronics" =
3rdEd.,=20
Radio Shack;"Principals of Electricity Applied to Telephone and =
Telegraph=20
Work" 1953; "Semi-conductor Reference Guide"1985; =
"Essential=20
Characteristics Principals, Ratings, Electrical and Physical=20
Characteristics" 10th ed., GE; "The Technical Report - Its'=20
preparation, processing and use in industry and government" 1954;=20
"Electrical Communication" by Albert 1940; "Installation =
and=20
Maintenance of Electrical Supply and Communication Lines" 1949, =
U.S. Govt.;=20
"Electrical Engineers Handbook - Electric Communication and=20
Electronics" by Pender & McIlwain, 4th ed. 1950; "Rodget's =
Dictionary of Electrical Terms" 3rd Ed. 1938; "Preparation of=20
Engineering Reports" Agg & Foster, 1st Ed. 1935; =
"Telephone Theory=20
and Practice" Miller 1st Ed. 1933; "Aircraft Radio and =
Electrical=20
Equipment" by Morgan 1939; "Radiotron Designer's =
Handbook" 3rd=20
ed., 1941; "Principals of Electricity Applied to Telephone and =
Telegraph=20
Work" 1929 AT&T; "The Computer Revolution" by =
Berkeley, 1962;=20
"Mathematics for Self Study" Thompson, 14th printing, 1931; =
"How=20
to Pass Radio License Examinations" 1952; "Radio =
Engineering"=20
Terman 3rd ed., 1947; "Measurements in Radio Engineering" by =
Terman=20
1st ed. 10th impression, 1935; "Measurements in Radio =
Engineering" by=20
Terman 1st ed. 4th impression, 1935; "Amateur Single Side =
Band"=20
Collins Radio Co. 1962; "Radio Amateur's Handbook" 21st Ed. =
1944=20
American Radio Relay League; "Radio Amateurs Handbook" 1968 =
American=20
Radio Relay League; "Radio Amateur's License Manual" 35th ed.=20
;"Relay Engineering" by Packard 1st ed.=20
1945.<BR></FONT></DIV></DIV></BODY></HTML>
- ------=_NextPart_000_0067_01C0322E.567B9D00--
=========================================================================
From: StepHydro@aol.com
Subject: Re: [JN] Garage sale , Books: Learners take note
Date: Tue, 10 Oct 2000 05:45:34 EDT
Source: Sound Digest Archive v02.n690
Ed has a couple of copies of the ARRL Radio Amateur's Handbook in that group.
It is one of the most recommended texts for learning tube theory from the
ground up. I started with that book, a 1957 edition, in the eighth grade and
am still at it 43 years later.
Hmm...WARNING, NEWBIES; STAY AWAY FROM THOSE BOOKS !!!
Cheers/Carron
:-) :-) :-) :-) :-) :-) :-) :-)
=========================================================================
From: Simon Busbridge <S.C.Busbridge@bton.ac.uk>
Subject: Re: [JN] Garage sale , Books: Learners take note
Date: Tue, 10 Oct 2000 12:00:29 +0100 (BST)
Source: Sound Digest Archive v02.n690
I have a 1946 copy. Wonderful book! If only we could still
buy the products listed in the adverts.....
Si,on
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
On Tue, 10 Oct 2000 StepHydro@aol.com wrote:
> Ed has a couple of copies of the ARRL Radio Amateur's Handbook in that group.
> It is one of the most recommended texts for learning tube theory from the
> ground up. I started with that book, a 1957 edition, in the eighth grade and
> am still at it 43 years later.
>
> Hmm...WARNING, NEWBIES; STAY AWAY FROM THOSE BOOKS !!!
>
> Cheers/Carron
> :-) :-) :-) :-) :-) :-) :-) :-)
>
=========================================================================
From: Jeff Mai <j.mai.lists@home.com>
Subject: Re: [JN] Garage Sale Update
Date: Sun, 15 Jul 2001 08:33:55 -0600
Source: Sound Digest Archive v02.n925
Thanks everyone for your responses.
First, I'll point out that I'm in the US, for everyone concerned
about shipping the heavy items. I neglected to mention this in my
initial message.
Second, I failed to make it clear, I think, that I intend to field
offers for the whole lot first (or at least most of it) before
selling the individual lots. I'll hold off on selling the individual
lots until Tuesday evening. At that point it will be first come,
first serve, so go ahead and email me what bits you're interested in
now. Many have already done so.
Interestingly, no two people have wanted the same item as of Sunday,
8:30 AM MDT, so if you've sent your email before then, you're first
in line for the items you've requested. I'll be contacting you
Tuesday or Wednesday if I get no offers on the whole lot.
Thanks again,
Jeff
=========================================================================
From: Jeff Mai <j.mai.lists@home.com>
Subject: Re: [JN] Garage Sale Update II
Date: Sun, 15 Jul 2001 10:35:13 -0600
Source: Sound Digest Archive v02.n925
Unless an offer is accepted on the whole mess (see earlier list),
here's what lots are still available. Don't forget to ask for the
free lots if want them thrown in or to make offers on things you want
but think are too pricey.
At 10:40 PM -0600 7/14/01, Jeff Mai wrote:
>Lot #2: http://members.home.com/j.mai.lists/garagesale/101-0102_IMG.JPG
>Large, vintage Hammond plate transformer. Type 720X60 , 250 VA.
>Current model 720 is 1250 VCT @ 300ma, but this would exceed the
>250VA rating. It's exactly the same core size as that model,
>though. Way cool name plate, but some rust. With a little
>refinishing this would look really trick. $30
>
>Lot #3: http://members.home.com/j.mai.lists/garagesale/101-0103_IMG.JPG
>Big Freed Choke. 2.5 HY, 700ma, 43V RMS, 23 ohms, 1000V WV. Cap
>input only, I'm guessing from the RMS rating. $15
>
>Lot #5: http://members.home.com/j.mai.lists/garagesale/101-0105_IMG.JPG
>Dual choke. 2 * 4 HY, 120 ma, 150V RMS, 47 ohms, 300V WV. $15
>
>Lot #6: http://members.home.com/j.mai.lists/garagesale/101-0106_IMG.JPG
>Monster home brew aircore coils. A lot of freakin' work! Between 6
>and 7 mH (I never measured them), 12 ga wire. Low DCR. $15 the
>pair
>
>Lot #9: http://members.home.com/j.mai.lists/garagesale/101-0109_IMG.JPG
>RCA cables. 5 stereo pairs. Cheap stuff except for one Monster
>Cable pair (which was still cheap, just not as cheap.) $5
>
>Lot #10: http://members.home.com/j.mai.lists/garagesale/101-0110_IMG.JPG
>Microphone. Stereo miniplug. Ultra cheap; came with computer.
>I'll throw it in with something else if you want it.
>
>Lot #11: http://members.home.com/j.mai.lists/garagesale/101-0111_IMG.JPG
>A lot of terminated coaxial video cable. One S-VHS cable. $5
>
>Lot #12: http://members.home.com/j.mai.lists/garagesale/101-0112_IMG.JPG
>Cheap plastic project box. Knobs, pots, RCA jacks. Free with purchase!
>
>Lot #13: http://members.home.com/j.mai.lists/garagesale/101-0113_IMG.JPG
>Wall wart. 14 VDC @ 850 ma. $5
>
>Lot #14: http://members.home.com/j.mai.lists/garagesale/101-0114_IMG.JPG
>Big pile 'o caps. Except for the two Techtronix branded caps at
>left, they're pretty much all electrolytics. Most of them are NOS
>low voltage. $10
>
>Lot #15: http://members.home.com/j.mai.lists/garagesale/101-0115_IMG.JPG
>Odd tube sockets. A nine pin mini Vector socket and two 7 pin mini
>adapters with test points. Freebie with other stuff.
>
>Lot #18: http://members.home.com/j.mai.lists/garagesale/101-0118_IMG.JPG
>Misc unknown transformers. Two in front are fil trans I bought for
>6B4Gs. They are either 12.6VCT @ 0.6 amp or 6.3VCT @ 1.2 amp. The
>others are unmarked and unknown. $10
>
>Lot #19: http://members.home.com/j.mai.lists/garagesale/101-0119_IMG.JPG
>Pair UTC 20VCT fil trans. $10
>
>Lot #20: http://members.home.com/j.mai.lists/garagesale/101-0120_IMG.JPG
>Smaller homebrew aircore coils. Between 1 and 2 mH. 12 ga. Low DCR. $7
>
>Lot #21: http://members.home.com/j.mai.lists/garagesale/101-0121_IMG.JPG
>Unknown chokes. $5
>
>Lot #22: http://members.home.com/j.mai.lists/garagesale/101-0122_IMG.JPG
>NOS Thordarson Fil Trans. 6.3VCT @ 0.6 amps. $5
>
>Lot #29: http://members.home.com/j.mai.lists/garagesale/101-0129_IMG.JPG
>Surgistor? Unknown pot with switch. 100 ohm 10 turn WW pot. Misc
>ICs. Throw in.
>
>Lot #30: http://members.home.com/j.mai.lists/garagesale/101-0130_IMG.JPG
>Big unknown plate and fil trans. It's the same size as the Hammond
>above. I measured it once upon a time and it was well over 1000VCT
>with no load. $20
>
>Lot #31: http://members.home.com/j.mai.lists/garagesale/101-0131_IMG.JPG
>Avel Toroid. 18V + 18V. Dual 120V primaries. Model D4030. $15
>
>Lot #32: http://members.home.com/j.mai.lists/garagesale/101-0132_IMG.JPG
>Pair Triad Universal OPTs. 12 Watts. Small. No connection diagram
>or specs. I got these once upon a time from Ed Bilecci. He may
>have more info. $15
>
>Lot #33: http://members.home.com/j.mai.lists/garagesale/101-0133_IMG.JPG
>Unknown trans. Decent sized. I'll include with lot #18.
>
>Lot #34: http://members.home.com/j.mai.lists/garagesale/101-0134_IMG.JPG
>Pair mil surplus plate and fil trans. 720VCT @ 125 ma, 6.3VAC @
>3.5A, 6.3VAC @ 2A. Dual 115V primaries. Two terminals were broken
>off one unit. I repaired with wire. Work fine. Great for
>monoblock amps. $30
>
>Lot #35: http://members.home.com/j.mai.lists/garagesale/101-0135_IMG.JPG
>Huge WE 354A MV rectifier. Base loose. I doubt it works but don't
>know for sure. Free.
>
>Lot #36: http://members.home.com/j.mai.lists/garagesale/101-0136_IMG.JPG
>Delco 50 tube. Looks and tests as new. Let's call it lightly used. $100
>
>Lot #38: http://members.home.com/j.mai.lists/garagesale/101-0138_IMG.JPG
>Pair NIB Valve Art 2A3. $30
>
>Lot #40: http://members.home.com/j.mai.lists/garagesale/101-0140_IMG.JPG
>NIB Cetron 323B MV thyratron. $5
>
>Lot #41: http://members.home.com/j.mai.lists/garagesale/101-0141_IMG.JPG
>Pair RCA 80 rectifiers. Used. One boxed. $12
>
>Lot #42: http://members.home.com/j.mai.lists/garagesale/101-0142_IMG.JPG
>Misc tubes. 3 * NEC 6AR5, NEC 12AT7, NEC 6CA4, all pulls. 6D6,
>6DM4, 2X2, 2C53, 2 * 6F4. $5
>
>Lot #44: http://members.home.com/j.mai.lists/garagesale/101-0144_IMG.JPG
>Philips 5U4GB, used. $5
>
>Lot #45: http://members.home.com/j.mai.lists/garagesale/101-0145_IMG.JPG
>4 NOS Tung-Sol 6AX5GT. Nice little rectifiers with 6.3VAC fils. $10
>
>Lot #46: http://members.home.com/j.mai.lists/garagesale/101-0146_IMG.JPG
>10 Misc 6AC7. Mostly GE and Ken-Rad despite what the boxes say.
>Some rattle a bit. No way to test. I'll guarantee 4 are good
>(unless I wind up giving them away, of course.) $7
>
>Lot #48: http://members.home.com/j.mai.lists/garagesale/101-0148_IMG.JPG
>2 NOS 12AX7. Stinky boxes. $10
=========================================================================
From: pderl@btinternet.com
Subject: Re: [JN] Re: Garrard 301's and Ortofon SPU's
Date: Mon, 15 Oct 2001 09:55:54 +0100 (BST)
Source: Sound Digest Archive v02.n993
The simplest way to identify a grease-bearing 301 is to look at the bearing housing for the greaser!
Mine no longer has a greaser as it has been upgraded. My man tells me that these greasers never wor
ked properly anyway - and the arrangement at the bottom i.e. the "bearing" is from an engineering po
int of view, really rather nasty.
Sounds excellent now though!
Paul
> Hi all,
>
> Regarding the Garrard 301, I have inherited* one from an old friend. * I've
> known of it for years, and I could probably have had it a while back for the
> peppercorn.
>
> On the front name plate is Schedule 51400 / 2 and a black square , the base
> is ivory but I think it still might be a grease bearing job, because of that
> 2.
>
> Is it?
>
> with the TT came an original plywood two layer plinth with the little
> springs and an old Ortofon arm.
>
> but here's the killer there are three Ortofon 'heads'. none with built in
> transformers, the two separate original coils, which I saw a long while back
> have been mislaid.
>
> I reckon one will be for 78's, one for mono Lp's and one will be stereo. any
> guidance on how to pick them apart?
>
>
>
> Timbo in Oz
>
=========================================================================
From: "Timothy James Bailey" <tim_bailey@bigpond.com>
Subject: [JN] Re: Garrard 301's and Ortofon SPU's
Date: Mon, 15 Oct 2001 13:12:48 +1000
Source: Sound Digest Archive v02.n993
Hi all,
Regarding the Garrard 301, I have inherited* one from an old friend. * I've
known of it for years, and I could probably have had it a while back for the
peppercorn.
On the front name plate is Schedule 51400 / 2 and a black square , the base
is ivory but I think it still might be a grease bearing job, because of that
2.
Is it?
with the TT came an original plywood two layer plinth with the little
springs and an old Ortofon arm.
but here's the killer there are three Ortofon 'heads'. none with built in
transformers, the two separate original coils, which I saw a long while back
have been mislaid.
I reckon one will be for 78's, one for mono Lp's and one will be stereo. any
guidance on how to pick them apart?
Timbo in Oz
=========================================================================
From: Henry Platt <hnplatt@massed.net>
Subject: Re: [JN] Garrard at 60Hz?
Date: Sun, 18 Jun 2000 20:42:22 -0400
Source: Sound Digest Archive v02.n584
Hi Peter,
Good to hear from you! How is winter down under?
I got mine from Martin Bastin. He's a terrific guy who makes all sorts of
Garrard related stuff. The 60 hz pulley he made for my 401 is superb.
Caution: The bronze on this one is almost paper thin, so handle with care.
Cost me 20 bucks USD and took a couple of weeks.
Martin Bastin
225 Tettenhall Rd.,
Wolverhampton,
West Midlands,
WV6 ODE.
UK
Regards,
Henry
> From: Martin/Campbell family <martincampbell@apex.net.au>
> Date: Mon, 19 Jun 2000 09:17:15 +1000
> To: <Sound@io.com>
> Subject: [JN] Garrard at 60Hz?
>
> I have a Garrard 301 that I am planning to put on Ebay soon. Many of the
> potential buyers will be in the USA. Does anyone know of a supplier of 60Hz
> pulleys for the 301/401? It would be usefull for me to be able to mention
> such a source in the ad.
>
> NB. The voltage is not a problem; that can be selected on the motor.
> Peter Campbell
>
>
=========================================================================
From: Martin/Campbell family <martincampbell@apex.net.au>
Subject: [JN] Garrard at 60Hz?
Date: Mon, 19 Jun 2000 09:17:15 +1000
Source: Sound Digest Archive v02.n584
I have a Garrard 301 that I am planning to put on Ebay soon. Many of the
potential buyers will be in the USA. Does anyone know of a supplier of 60Hz
pulleys for the 301/401? It would be usefull for me to be able to mention
such a source in the ad.
NB. The voltage is not a problem; that can be selected on the motor.
Peter Campbell
=========================================================================
From: Paolo Del Giusto <paolo.delgiusto@studioidea.it>
Subject: [JN] Garrard & phono preamp
Date: Wed, 10 May 2000 13:01:53 +0200
Source: Sound Digest Archive v02.n542
Hi all!!!
Nice day here in Italy, the summer is coming!
In a spring clearance I found a Garrard 301 in (I hope) usable conditions.
The arm seems Garrard too, but I've heard it isn't a good choice. What do
you suggest? The Rega RB250 would be a better candidate? At least it is,
regarding the budget.......
I'm also looking for a simple and good sounding (often this means the same
thing) phono preamp: any suggestion?
Thanks in advance!
Ciao!!
P.S.: since I'm a novice in the analogue world, could someono please
explain me the differences, building and sounding, between MC and MM
cartridges?
- -------------------------------------------------
- ----------------Paolo Del Giusto-----------------
- -------------------------------------------------
- ----------paolo.delgiusto@studioidea.it----------
- -------------------------------------------------
=========================================================================
From: David Crittle <retrovox@bigpond.com>
Subject: [JN] Garrard & phono preamp
Date: Thu, 11 May 2000 11:17:31 +1000
Source: Sound Digest Archive v02.n543
studioidea.it/paolo.delgiusto@pop.inet.it wrote:
>Date: Wed, 10 May 2000 13:01:53 +0200
>
>Nice day here in Italy, the summer is coming!
>
>In a spring clearance I found a Garrard 301 in (I hope) usable conditions.
>The arm seems Garrard too, but I've heard it isn't a good choice. What do
>you suggest? The Rega RB250 would be a better candidate? At least it is,
>regarding the budget.......
Summer in Italy, sounds good!
http://weather.yahoo.com/regional/Italy.html
Starting to cool down here in Wagga Wagga. Bright days and cool nights
right now, blankets back on the bed. Gets cold in wintertime here,
sometimes at night in winter it is below zero. I was born here 36 years ago
and never seen snow. Saw some snow once on a bus trip in the mountains when
I was a kid. Looked cold and wet (which is how I like my beer)
http://weather.yahoo.com/forecast/Wagga_AU_c.html
I have some NOS tonearms which a number of joes have tried. No one has
actually got back to me and told me how they went....anyone actually used
them yet?
There's a 1950's advert for the 301, plus pic and specs of the S-220
tonearm, at this link:
http://albums.photopoint.com/j/AlbumIndex?u=149682&a=1773196
David
=========================================================================
From: "Martin/Campbell family" <martincampbell@apex.net.au>
Subject: [JN] Garrard/SME3012/Infinity Black Widow/Michell Hydraulic reference
Date: Wed, 26 May 1999 17:14:14 +1000
Source: Sound Digest Archive v02.n152
Hello all,
Probably no-one noticed but I havn't been here for the last 6 months or so.
I have a bunch of new toys and a few questions. Nothing much in the way of
actually work on projects; only fixing the odd problem. Resoldering the
lead out wire to the voice coil of a Tannoy dual concentric tweeter is not
easy. Yes, Paul (if you're there) I will get around to using your chokes!
I bought a used Garrard 301 with SME 3012 arm and very rough plinth. It
needs some work so I'd appreciate any comments/advice. Specifically, the
bearing may need some work or maybe replacement. Any opinions on the
various companies who do Garrard stuff? The 3012 arm looks OK except the
rubber decoupling bit between the bearing and the counter weight is broken
through. I'll have to track this part down. I hope I can get it.
I got another arm, an Infinity "Black Widow" graphite fibre. Is this one
any good?
Does anyone happen to know the effective masses for either of these arms?
I also picked up a Michell Hydraulic reference turntable (late 60's/early
70's). This apparently known for being featured in "A clockwork orange"
and looking like the space station in "2001-A space oddessy"; Michell was a
set designer for both films. A friend might buy this one when I have fixed
the switch and strobe lamp. Does anyone have an opinion about it's value?
It goes to the opposite extreme of the idea of clamping records to a massive
plinth. Instead it has a heavy platter with six pods on top. These are
topped with small rubber dots. The record is supported only by those six
points. The closest you could get to a Platter-less turntable. I guess it
is the same sort of idea as the ring mat.
Peter Campbell
=========================================================================
From: "Farwell-Clay" <wclay@mediaone.net>
Subject: [JN] Gary's grid/plate cap need...
Date: Fri, 15 Dec 2000 20:07:53 -0500
Source: Sound Digest Archive v02.n760
Hey Gary,
I hate to see a man suffer...How many of these things do you need? I'm sure
I have a few here in Newburyport you can have. Send me an email and I'll get
them to you.
Walter Clay
=========================================================================
From: Grover Gardner <groverg@postoffice.att.net>
Subject: [JN] Gas diodes as bias?
Date: Mon, 20 Aug 2001 09:28:43 -0400
Source: Sound Digest Archive v02.n950
If one uses a gas diode, like the OC3, to bias a power tube, what
happens with the diode's max current rating? Is the power tube's bias
determined by the diode's current capability or by the cathode voltage
the diode creates? For example, if I want to bias a 300B at 90
volts/60mA, will a 90 volt diode do this, or will it limit the current?
- --
Grover Gardner
groverg@postoffice.att.net
Visit my web site at http://home.att.net/~groverg/homepage.htm
=========================================================================
From: Roscoe Primrose <roscoe@aiko.com>
Subject: Re: [JN] Gas diodes as bias?
Date: Mon, 20 Aug 2001 09:52:30 -0400
Source: Sound Digest Archive v02.n950
Grover Gardner wrote:
> If one uses a gas diode, like the OC3, to bias a power tube, what
> happens with the diode's max current rating? Is the power tube's bias
> determined by the diode's current capability or by the cathode voltage
> the diode creates? For example, if I want to bias a 300B at 90
> volts/60mA, will a 90 volt diode do this, or will it limit the current?
>
>
That would work, but the OC3 is only rated at 40mA max, so you'd
probably significantly reduce the life...
Peace--
Roscoe Primrose -- mailto:roscoe@aiko.com -- http://www.aiko.com/roscoe
"Once in a while you get shown the light
In the strangest of places if you look at it right." Robert Hunter
"640K ought to be enough for anybody" , Bill Gates, 1981
=========================================================================
From: TubeGarden@aol.com
Subject: Re: [JN] Gas diodes as bias?
Date: Mon, 20 Aug 2001 09:58:55 EDT
Source: Sound Digest Archive v02.n950
- --part1_fc.aef10af.28b2719f_boundary
Content-Type: text/plain; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
Greets!
Dunno gas diodes.
St B used one i think...
I biased 300B with 3 each 6X5GT in series, top one split one plate to each
300B cathode. Gave 60 mA at 66 volts bias.
Sounded OK :)
Happy Ears!
Al B^}
- --part1_fc.aef10af.28b2719f_boundary
Content-Type: text/html; charset="US-ASCII"
Content-Transfer-Encoding: 7bit
<HTML><FONT FACE=arial,helvetica><BODY BGCOLOR="#ffffff"><FONT SIZE=2>Greets!
<BR>
<BR>Dunno gas diodes.
<BR>
<BR>St B used one i think...
<BR>
<BR>I biased 300B with 3 each 6X5GT in series, top one split one plate to each
<BR>300B cathode. Gave 60 mA at 66 volts bias.
<BR>
<BR>Sounded OK :)
<BR>
<BR>Happy Ears!
<BR>Al B^}
<BR>
<BR></FONT></HTML>
- --part1_fc.aef10af.28b2719f_boundary--
=========================================================================
From: S.C.Busbridge@bton.ac.uk
Subject: RE: [JN] Gas diodes as bias?
Date: Mon, 20 Aug 2001 14:35:47 +0100
Source: Sound Digest Archive v02.n950
Grover,
I think that you can push all the current you want through a gas discharge
regulator, which is why you have to insert some series impedance in the
circuit. So the answer to you question is no it will not limit the current
- - but - you need rather more than the running voltage to strike a gas
discharge valve before it will pass any current at all.
Simon
Simon Busbridge, BSc(Hons) PhD CPhys MInstP
School of Engineering
University of Brighton
Lewes Road
Moulsecoomb
Brighton BN2 4GJ
UNITED KINGDOM
Tel: 0044 (0)1273 642542
Fax: 0044 (0)1273 642327/642301
e-mail: s.c.busbridge@bton.ac.uk, scbusbridge@hotmail.com
Audio www site: http://audio.eng.bton.ac.uk
> ----------
> From: Grover Gardner[SMTP:groverg@postoffice.att.net]
> Reply To: groverg@postoffice.att.net
> Sent: 20 August 2001 14:28
> Cc: sound@lists.io.com
> Subject: [JN] Gas diodes as bias?
>
> If one uses a gas diode, like the OC3, to bias a power tube, what
> happens with the diode's max current rating? Is the power tube's bias
> determined by the diode's current capability or by the cathode voltage
> the diode creates? For example, if I want to bias a 300B at 90
> volts/60mA, will a 90 volt diode do this, or will it limit the current?
>
> --
> Grover Gardner
> groverg@postoffice.att.net
> Visit my web site at http://home.att.net/~groverg/homepage.htm
>
=========================================================================
From: SBench@aol.com
Subject: Re: [JN] Gas diodes as bias?
Date: Tue, 21 Aug 2001 00:37:27 EDT
Source: Sound Digest Archive v02.n951
In a message dated 01-08-20 09:29:30 EDT, groverg@postoffice.att.net writes:
>
> If one uses a gas diode, like the OC3, to bias a power tube, what
> happens with the diode's max current rating? Is the power tube's bias
> determined by the diode's current capability or by the cathode voltage
> the diode creates? For example, if I want to bias a 300B at 90
> volts/60mA, will a 90 volt diode do this, or will it limit the current?
>
Hi Grover and all,
to bias a 300B at 90V/60mA, you'd be overlaoding the gas tube. Those
critters behave pretty much like a zener diode with the following exceptions:
1. Starting voltage is higher than their regulating voltage. Only drawback in
your mentioned circuit is a small audible "pop" as they ionize.
2. They do NOT like to be significantly overloaded. At 60 mA, some devices
will enter arc discharge region. This is not good, as the voltage drop
across the tube goes DOWN (a.k.a. negative resistance) There's a
good description of this in "Electronic Designers Handbook" (Mc Graw
Hill. 1957. Landee, Davis, Albrecht) (and one of my bibles). The net
effect
is a bad bias condition on a relatively expensive 300B.
(Incidentally, these two combine to show why NOT to put a large capacitor
across the gas tube: you get a nice relaxation oscillator while it lasts.)
What you *could* do is use 2- 0B3s in parallel but equalized by 75 ohm
resistors in series with each one. The combined equivalent 37.5 ohms should
not seriously affect the sonics.
Best Regards,
Steve
=========================================================================
From: Thomas Danley <Tom@ppci.com>
Subject: [JN] Gas music from Jupiter (actually kinda cool)
Date: Thu, 13 Jul 2000 19:58:48 -0500
Source: Sound Digest Archive v02.n603
Hi
A fellow on the Bass list saw this and thought of my old engines and me
bless his heart.
I can't really say that I want one of these for my backyard but it is
cool and worth an "A" for originality.
Anyway check out the link.
> From:
> "Ron Erickson"
> To:
> bass@lists.cc.utexas.edu
>
>
>
> A pipe organ for Tom Danley? ;-)
>
> http://www.lhpo.org/
>
> Ron Erickson
>
=========================================================================
From: "Geoffrey Barre" <ael34@magma.ca>
Subject: [JN] gassy tubes
Date: Sat, 15 Sep 2001 20:13:20 -0400
Source: Sound Digest Archive v02.n975
I recently bought a pair of 45s. When I inspected them at home I noticed
that one had greyish patches on the getter and the other a grayish strip
near the base (not the whole getter). Not having a tube tester or an amp
(yet) to test them in, is there any way of telling whether these are too
gassy to use?
/geoff
=========================================================================
From: Ross J Lahlum <rlahlum@juno.com>
Subject: [JN] Gates Gel Cells
Date: Wed, 22 Dec 1999 20:18:38 -0600
Source: Sound Digest Archive v02.n370
Hey Joes,
I thought I hit it big when I bought 2 UPS supplies for $15 apiece at the
local surplus shop that each had 14 Gates Cyclon 2.5 Amp-Hour gel cells.
Now it looks like I have a lot of dead lead to dispose of. None of them
will take a charge. Anybody know of a way to bring dead gel cells back
to life?
TIA,
Ross
___________________________________________________________________
Why pay more to get Web access?
Try Juno for FREE -- then it's just $9.95/month if you act NOW!
Get your free software today: http://dl.www.juno.com/dynoget/tagj.
=========================================================================
From: Chris Beck <n9zes@execpc.com>
Subject: Re: [JN] Gates Gel Cells
Date: Wed, 22 Dec 1999 21:46:22 -0600
Source: Sound Digest Archive v02.n370
Sorry, Ross. Typically gel cells are dead, finito, au revoir, that's all
folks, when they are bad they are bad. No way to bring them back, except
trying a really long, slow charge cycle. Maybe a few hundred mA for several
days. Don't hold your breath, tho.
Merry Christmas???
Chris
Do make a point of properly recycling those, tho. Most places have dropoff
centers. That's a lot of lead.
Ross J Lahlum wrote:
> Hey Joes,
>
> I thought I hit it big when I bought 2 UPS supplies for $15 apiece at the
> local surplus shop that each had 14 Gates Cyclon 2.5 Amp-Hour gel cells.
> Now it looks like I have a lot of dead lead to dispose of. None of them
> will take a charge. Anybody know of a way to bring dead gel cells back
> to life?
>
> TIA,
> Ross
>
> ___________________________________________________________________
> Why pay more to get Web access?
> Try Juno for FREE -- then it's just $9.95/month if you act NOW!
> Get your free software today: http://dl.www.juno.com/dynoget/tagj.
=========================================================================
From: "Carter Hendricks" <carter@i1.net>
Subject: Re: [JN] Gates Gel Cells
Date: Wed, 22 Dec 1999 23:00:12 -0600
Source: Sound Digest Archive v02.n370
- -----Original Message-----
From: Chris Beck <n9zes@execpc.com>
To: Ross J Lahlum <rlahlum@juno.com>
Cc: sound@deliverator.io.com <sound@deliverator.io.com>
Date: 22 December, 1999 10:29 PM
Subject: Re: [JN] Gates Gel Cells
> Sorry, Ross. Typically gel cells are dead, finito,
> au revoir, that's all folks, when they are bad they
> are bad. No way to bring them back, except
> trying a really long, slow charge cycle.
I've had some luck with one trick which can work
on discharged cells: a small lamp across the
terminals with the charger, just a little something
to draw some current...
--Carter
=========================================================================
From: Peter Sikking <guigurus@xs4all.nl>
Subject: [JN] Gaussian filter values...
Date: Thu, 18 Nov 1999 17:39:51 +0000
Source: Sound Digest Archive v02.n336
Hi Joesters,
can somebody with a bigger library than mine give me the normalized filter
values for single resistance terminated Guassian passive ladder lo-pass filters.
2-8th order if available with normalization.
I'd be most grateful.
--Peter
: music lover : ultra-fi builder : ui & oo designer & developer : on drums...
: from:amsterdam@berlin : +49 173 800 60 37 : facsimile +49 30 390 94 300
=========================================================================
From: tube@jump.net
Subject: Re: [JN] Gaussian filter values...
Date: Sun, 21 Nov 1999 14:25:02 -0600
Source: Sound Digest Archive v02.n339
Peter Sikking wrote:
> Hi Joesters,
>
> can somebody with a bigger library than mine give me the normalized filter
> values for single resistance terminated Guassian passive ladder lo-pass filters.
>
> 2-8th order if available with normalization.
>
> I'd be most grateful.
>
> --Peter
>
> : music lover : ultra-fi builder : ui & oo designer & developer : on drums...
> : from:amsterdam@berlin : +49 173 800 60 37 : facsimile +49 30 390 94 300
Peter,
I don't have the ladder values, but I can give you the filter pole positions
for pretty much any order of Gaussian filter you want. I also have specific
values for a 7-pole filter broken down into three isolated 2-pole, 2-pole,
and 3-pole sections. I have only been able to use them by setting up a 2
or 3 pole L-C-R section on the computer, letting it tell me what the pole
positions are, and then using trial and error to get the pole positions I
need. A serious pain! Unfortunately, trial and error is the rule in filters--
and believe me, I tried for a LONG time to get the Gaussian values from
anyone else, rather than resort to trial and error methods.
Of course, the last time I really studied this situation was about 10 years
ago, so maybe there are computer programs that will give you R, L, and
C values if you specify the pole positions and initial resistor values.
Maybe someone else out there has such a beast? If you've got the
program, I've got the pole positions ...
Just out of curiosity, what led you to an interest in Gaussian filters? I have
long suspected that it might be the best filter configuration of them all, but
most people use Bessel or various other filters. In fact, I think you are the
first person to even bring up the subject that I have seen.
Phil
=========================================================================
From: "Daniel J. Marshall" <danmarshall@worldnet.att.net>
Subject: Re: [JN] Gaussian filter values...
Date: Sun, 21 Nov 1999 14:40:27 -0800
Source: Sound Digest Archive v02.n340
Hi,
I have a table for Gaussian filter values which I posted a couple years
ago. In fact, I just came across that old post when doing some computer
housecleaning yesterday. The table is for equal resistance in/out and
the original request was for a single-resistor filter, which I presume
to mean a filter designed to operate from a very low impedance (an amp
output) into a specified impedance (a speaker), so, I didn't bother to
repost it. I can repost the table and scaling formulas if anyone wants
them. The values are normalized for 1 ohm in/out and one radian/sec.
Scaling formulas are given to quickly scale the values to any desired
frequency and impedance. As I recall, they go from 2 through 9
elements. I will be going off-line early tomorrow morning for more than
a week, so if interested speak up before then and I'll diog it oput and
repost it.
Dan Marshall
tube@jump.net wrote:
>
> Peter Sikking wrote:
>
> > Hi Joesters,
> >
> > can somebody with a bigger library than mine give me the normalized filter
> > values for single resistance terminated Guassian passive ladder lo-pass filters.
> >
> > 2-8th order if available with normalization.
> >
> > I'd be most grateful.
> >
> > --Peter
> >
> > : music lover : ultra-fi builder : ui & oo designer & developer : on drums...
> > : from:amsterdam@berlin : +49 173 800 60 37 : facsimile +49 30 390 94 300
>
> Peter,
>
> I don't have the ladder values, but I can give you the filter pole positions
> for pretty much any order of Gaussian filter you want. I also have specific
> values for a 7-pole filter broken down into three isolated 2-pole, 2-pole,
> and 3-pole sections. I have only been able to use them by setting up a 2
> or 3 pole L-C-R section on the computer, letting it tell me what the pole
> positions are, and then using trial and error to get the pole positions I
> need. A serious pain! Unfortunately, trial and error is the rule in filters--
> and believe me, I tried for a LONG time to get the Gaussian values from
> anyone else, rather than resort to trial and error methods.
>
> Of course, the last time I really studied this situation was about 10 years
> ago, so maybe there are computer programs that will give you R, L, and
> C values if you specify the pole positions and initial resistor values.
> Maybe someone else out there has such a beast? If you've got the
> program, I've got the pole positions ...
>
> Just out of curiosity, what led you to an interest in Gaussian filters? I have
> long suspected that it might be the best filter configuration of them all, but
> most people use Bessel or various other filters. In fact, I think you are the
> first person to even bring up the subject that I have seen.
>
> Phil
=========================================================================
From: Peter Sikking <guigurus@xs4all.nl>
Subject: Re: [JN] Gaussian filter values...
Date: Mon, 22 Nov 1999 17:50:34 +0000
Source: Sound Digest Archive v02.n340
Phil wrote:
> > can somebody with a bigger library than mine give me the normalized filter
> > values for single resistance terminated Guassian passive ladder lo-pass
> > filters.
> Of course, the last time I really studied this situation was about 10 years
> ago, so maybe there are computer programs that will give you R, L, and
> C values if you specify the pole positions and initial resistor values.
> Maybe someone else out there has such a beast? If you've got the
> program, I've got the pole positions ...
This weekend I found this:
http://www.kahlereng.com/filter/
Ten day _fully_ functional demo can be downloaded from there.
The first one I found that does Gauss and passive.
> Just out of curiosity, what led you to an interest in Gaussian filters? I have
> long suspected that it might be the best filter configuration of them all, but
> most people use Bessel or various other filters. In fact, I think you are the
> first person to even bring up the subject that I have seen.
Almost everybody in this cult has a high horse, and this is mine:
When I read a book about filters, I realised this:
- - The PS is a filter, not a battery.
- - The PS filter gets hit with voltage (AC changes) and current (music) transients
all the time.
- - Gaussian filters are the only ones that don't ring (make their own music) when
hit with a transient.
Only problem up to now was finding a book or program that covers Gauss and
passive. Now that I played with the program a bit I found that that series
resistance m,atters a lot (sounds familiar?).
Question to the whole Joenet:
Stealing Daniel's artwork:
R series L2
0-----\/\/\----*-----()()()()-----*---- - - - - ----|
| | |
| | LOAD
C1 ----- C3 ----- ETC. |
----- ----- TUBE
| | |
| | |
0--------------*------------------*---- - - - - ----|
The filter is terminated by the load and the tube.
I recently realised that the resistance of the tube is the Rp (sounds logical
now) instead of Vk-p/Ik-p.
But what about the load?
Is the filter terminated by Rp + Rload, in case of resistor load and resistor
terminated transformers?
And do I get an extra filter choke (Ln+1) just before the tube in case of
choke loading and unterminated (tube terminated) transformers?
If I know this I can go ahead and build it...
Thanks,
--Peter
: music lover : ultra-fi builder : ui & oo designer & developer : on drums...
: from:amsterdam@berlin : +49 173 800 60 37 : facsimile +49 30 390 94 300
=========================================================================
From: Peter Boser <pboser@yahoo.com>
Subject: [JN] GB tubes?
Date: Tue, 19 Jun 2001 10:31:33 -0700 (PDT)
Source: Sound Digest Archive v02.n913
I'm working out a trade with a guy in Britain who has
offered to look at his local TV repair shop for some
tubes among the zillions of NOS tubes the guy has.
Suggestions on what should be on the wish list I'm
going to send him?
Thanks,
Pete
__________________________________________________
Do You Yahoo!?
Spot the hottest trends in music, movies, and more.
http://buzz.yahoo.com/
=========================================================================
From: "Paul De Raymond Leclercq" <Pderl@btinternet.com>
Subject: Re: [JN] GB tubes?
Date: Tue, 19 Jun 2001 19:16:22 -0700
Source: Sound Digest Archive v02.n914
Well, it depends how old the stock is of course.
If the firm was long-established, I would suggest: L63; B36; B65;
KT61/66/88(!); EL34 (!); GZ34 (!) EL33. Most of the British TV valves are
less than worthless - few people seem to want to bother with series heaters
etc., but PCC88 is a perfectly usable ECC88 substitute, likewise PL84. Many
of these were manufactured by Mullard and by the thousand so I would expect
consistency.
I have a collection of PCC805s (= 30L15) these came from a loose box - and
every one is 100%
You can always ask about E810F (7788) and obviously ECC88/81/82/83
Certain old radio valves are of course, rare - I have been looking for an
X78 for years!
Best wishes
Paul (London)
- ----- Original Message -----
From: Peter Boser <pboser@yahoo.com>
To: <sound@lists.io.com>
Sent: Tuesday, June 19, 2001 10:31 AM
Subject: [JN] GB tubes?
> I'm working out a trade with a guy in Britain who has
> offered to look at his local TV repair shop for some
> tubes among the zillions of NOS tubes the guy has.
> Suggestions on what should be on the wish list I'm
> going to send him?
> Thanks,
> Pete
>
> __________________________________________________
> Do You Yahoo!?
> Spot the hottest trends in music, movies, and more.
> http://buzz.yahoo.com/
=========================================================================
From: "C.snoeren" <c.snoeren@tip.nl>
Subject: Re: [JN] GB tubes?
Date: Tue, 19 Jun 2001 23:53:05 +0200
Source: Sound Digest Archive v02.n914
Look for the real Brittain brands like Mullard Haltron and Brimar.
GZ32,34,37 rectifiers.
Sets of KT66/KT88
Sets of EL84 EL34 whatever European brand
PX4, PX25 , AD1 direct heated triodes
ECC32 (double triodes like the 6SN7GT)
And what he should have lots of are the ECC81,82,83,88 series.
Mesh plate rectifiers and triodes
But I don't know what kind of tubes you are looking for....
- --
Greetings,Cuno
mailto:c.snoeren@tip.nl
http://www.ariel.club.tip.nl
http://www.triode.club.tip.nl
Peter Boser schreef:
> I'm working out a trade with a guy in Britain who has
> offered to look at his local TV repair shop for some
> tubes among the zillions of NOS tubes the guy has.
> Suggestions on what should be on the wish list I'm
> going to send him?
> Thanks,
> Pete
>
> __________________________________________________
> Do You Yahoo!?
> Spot the hottest trends in music, movies, and more.
> http://buzz.yahoo.com/
=========================================================================
From: "Paul De Raymond Leclercq" <Pderl@btinternet.com>
Subject: Re: [JN] GB tubes?
Date: Wed, 20 Jun 2001 00:14:40 -0700
Source: Sound Digest Archive v02.n914
Most of the British brands (that were original manufacturers) were very
good: Mullard, Brimar, British Tungsram, Hivac, GEC/MOV/Marconi and STC.
STC used to own Brimar - it was the commercial arm of STC which made valves
largely for industry and the military. Later, (I believe after STC was
acquired by ITT, Brimar was sold to Thorn. In my opinion, Mullard was the
best of British - certainly on the receiving valve side. I have tested
ancient filthy EL84s that have been thrashed in guitar amplifiers that still
test at 95% whereas new Russian production are not in the same street.
Less easy to find are Ferranti. There were others: Emitron (EMI) Cossor
etc. There was also a group of "re-labellers" that did not manufacture
Haltron is a (good) example and the Pinnacle-branded valves were generally
good too. Often these were products of the leading manufacturers. As an
example I have some Haltron EC93s (=6BS4) These are probably from
Telefunken or Siemens and test superbly - similarly my Pinnacle 6BL7s -
almost certainly American production. However do NOT buy anything branded
"Bentley Acoustic Corporation". As far as I can make out this organisation
was run by a bunch of crooks. I have a pair of "EL37s" branded Bentley.
They are fourth-rate Chinese 6L6s!!
Best wishes and good hunting
Paul.
- ----- Original Message -----
From: C.snoeren <c.snoeren@tip.nl>
To: Peter Boser <pboser@yahoo.com>
Cc: <sound@lists.io.com>
Sent: Tuesday, June 19, 2001 2:53 PM
Subject: Re: [JN] GB tubes?
> Look for the real Brittain brands like Mullard Haltron and Brimar.
>
> GZ32,34,37 rectifiers.
> Sets of KT66/KT88
> Sets of EL84 EL34 whatever European brand
> PX4, PX25 , AD1 direct heated triodes
> ECC32 (double triodes like the 6SN7GT)
> And what he should have lots of are the ECC81,82,83,88 series.
> Mesh plate rectifiers and triodes
>
> But I don't know what kind of tubes you are looking for....
>
> --
> Greetings,Cuno
>
> mailto:c.snoeren@tip.nl
> http://www.ariel.club.tip.nl
> http://www.triode.club.tip.nl
>
> Peter Boser schreef:
>
> > I'm working out a trade with a guy in Britain who has
> > offered to look at his local TV repair shop for some
> > tubes among the zillions of NOS tubes the guy has.
> > Suggestions on what should be on the wish list I'm
> > going to send him?
> > Thanks,
> > Pete
> >
> > __________________________________________________
> > Do You Yahoo!?
> > Spot the hottest trends in music, movies, and more.
> > http://buzz.yahoo.com/
>
>
>
>
>
=========================================================================
From: "Anthony Knettel" <aknettel@mindspring.com>
Subject: [JN] gear 4 free if U haul
Date: Tue, 17 Apr 2001 23:28:53 -0400
Source: Sound Digest Archive v02.n868
I'm not sure this is going to work, but....
On Friday afternoon and Saturday morning (April 20th & 21st) I will be in
Lynbrook, New York (on the south shore of Long Island, a few miles north of
Sunrise Highway, maybe ten minutes outside Queens) clearing the last refuse
out of my father's house in preparation for its sale and settlement of his
estate. There is a six foot rack full of audio test equipment in the
basement I would like to save from the dumpster. If I remember correctly
(it's been a while) there is an O-scope (HP, I think), a signal generator, a
spectrum analyzer, a power supply or two, perhaps a rack-mounted amp.
There's some more gear stashed in a big file cabinet that I haven't even
looked at yet. Most, if not all, vintage tube units as far as I know. I
assume it is all in working condition but none of it has been powered up in
ten, perhaps fifteen, years so there are no guarantees. I don't have model
numbers, though I can look for them once I get there. Hmm, I almost forgot
. . . I think there is also a big open reel video machine too.
Unfortunately, I can't possibly keep this stuff myself, and I do not have
the time to sell it off in an organized manner or pack and ship it, so I
will give it away to any fellow Joelister who is willing to come pick it up
while I'm there and carry it away so it doesn't end up in a landfill. (If
you insist on offering me some cool tubes in trade I won't turn them down,
but you can have the gear for free.) If you're interested, here's the deal:
(1) I will give preference to the first person who promises to take it ALL,
even if they are not the first person who contacts me.
(2) If no one offers to take it all, then I'll give preference on individual
items in the order people contact me. PLEASE don't ask me to hold something
for you unless you are willing to make an iron-clad commitment to come pick
it up either Friday afternoon or Saturday morning - I don't want to turn
away someone who wants a particular item and then get stuck with it when the
person who asked me to hold it for them doesn't show up.
(3) If you're interested but don't want to make a commitment to take
something sight unseen - which is understandable - let me know when you'd
like to drop by to see what's left and we'll work out a mutually agreeable
time.
(4) If you'd really like this stuff but can't pick it up either Friday or
Saturday, I might be able to to work out alternative arrangements but it's a
long shot.
I'm sorry I can't be more flexible, but I'm traveling to NY from Washington
DC and my time there is very limited. If you are interested, contact me
off-list at aknettel@mindspring.com ASAP so I can give you the address and
find out when you intend to pick the stuff up (I will be in and out of the
house and need to know when to expect you).
Thanks for the bandwidth. -- Anthony Knettel
=========================================================================
From: David Crittle <retrovox@bigpond.com>
Subject: [JN] .GEC A2293 power triode
Date: Mon, 10 Jan 2000 14:31:11 +1100
Source: Sound Digest Archive v02.n393
Heard of this one, the GEC A2293 power triode? They were used in power
supplies, and I'm wondering if anyone has tried them for audio. It's a nine
pin miniature, the same size as a 6CA4 or 6QB5. I've seen amps with
transformer coupled (ie not OTL) 6080 and 6AS7G, perhaps this power triode
could be utilised in the same way.
Brief specs:
Indirectly (oh well) heated 6.3v @ 950mA
ra 375 ohms
15 watt plate
gm 12mA/V
300 volts max plate
120mA max current
See specs and curves at
http://albums.photopoint.c