(Tom Bruhns) wrote in message om...

Lots of discussion about using the 829 for VHF power amplifiers, and
even audio amplifiers and conversation pieces. But I haven't seen
mention here of their use in pulse generators.

Or CRT drivers (in the AN/APS-44 aircraft radar, and I think some of
the Navy PPI repeaters).

Perhaps someone knows: was the 3E29 an 829 re-designed and/or
specifically tested for use in pulsers?

Probably. 3E29 was used in the Mk III IFF interogators, circa 1943. I
don't know of any other major uses for the 3E29 (AKA 829A). Real 3E29s
are getting quite scarce, but 829Bs still can be found in biblical
quantities.

What was the 829 originally
intended for, and when was it first introduced? Who made the first
ones, RCA or someone else?

1943, probably RCA, although National Union was apparently an early
second source. 832 was the model for the 829.

William Donzelli

William Donzelli wrote in message
om...
(Tom Bruhns) wrote in message
om...

Lots of discussion about using the 829 for VHF power amplifiers, and
even audio amplifiers and conversation pieces. But I haven't seen
mention here of their use in pulse generators.

Or CRT drivers (in the AN/APS-44 aircraft radar, and I think some of
the Navy PPI repeaters).

Perhaps someone knows: was the 3E29 an 829 re-designed and/or
specifically tested for use in pulsers?

Probably. 3E29 was used in the Mk III IFF interogators, circa 1943. I
don't know of any other major uses for the 3E29 (AKA 829A). Real 3E29s
are getting quite scarce, but 829Bs still can be found in biblical
quantities.

What was the 829 originally
intended for, and when was it first introduced? Who made the first
ones, RCA or someone else?

1943, probably RCA, although National Union was apparently an early
second source. 832 was the model for the 829.

William Donzelli

I've seen references to the fact that the 829B was used in MIT's Whirlwind
computer as core memory drivers, definitely a pulse application. I don't
have any documentation on that, but I do remember some dual plate 829B-like
tubes in the Whirlwind fragments that used to be on display at the
now-defunct Boston Computer Museum. They could have been 3E29s, though, or
even 832s.

The Univac I used 829Bs, as documented here (5/8ths of the way down the
page):
http://ed-thelen.org/comp-hist/BRL61-u3.html

With that complement of tubes you could make one heck of an all-modes
transceiver!

William Donzelli wrote in message
om...
(Tom Bruhns) wrote in message
om...

Lots of discussion about using the 829 for VHF power amplifiers, and
even audio amplifiers and conversation pieces. But I haven't seen
mention here of their use in pulse generators.

Or CRT drivers (in the AN/APS-44 aircraft radar, and I think some of
the Navy PPI repeaters).

Perhaps someone knows: was the 3E29 an 829 re-designed and/or
specifically tested for use in pulsers?

Probably. 3E29 was used in the Mk III IFF interogators, circa 1943. I
don't know of any other major uses for the 3E29 (AKA 829A). Real 3E29s
are getting quite scarce, but 829Bs still can be found in biblical
quantities.

What was the 829 originally
intended for, and when was it first introduced? Who made the first
ones, RCA or someone else?

1943, probably RCA, although National Union was apparently an early
second source. 832 was the model for the 829.

William Donzelli

I've seen references to the fact that the 829B was used in MIT's Whirlwind
computer as core memory drivers, definitely a pulse application. I don't
have any documentation on that, but I do remember some dual plate 829B-like
tubes in the Whirlwind fragments that used to be on display at the
now-defunct Boston Computer Museum. They could have been 3E29s, though, or
even 832s.

The Univac I used 829Bs, as documented here (5/8ths of the way down the
page):
http://ed-thelen.org/comp-hist/BRL61-u3.html

With that complement of tubes you could make one heck of an all-modes
transceiver!

Hi,

The 3E29 may share a similar appearance, and the same pin out as the
829, but it certainly is not interchangable. To quote the RCA TT5
manual:

3E29: Heater-cathode type containing two high-perveance units used
as retangular-wave pulse modulator. Modulator Service maximum
CCS plate dissipation (per tube) 15watts.

Further down, it shows the plate supply voltage as 5000V, and the
instantaneous plate voltage as 5750V.

829: Heater-cathode type having midtapped heater used as af power
amplifier and modulator and as rf power amplifier and oscillator.

CCS dissipation is shown as 30W with natural cooling, and 40W with
forced air cooling.

It is pretty clear to me that the 3E29 was rearranged for high plate
voltage, and was used as a radar modulator tube. It is designed to
put out high voltage square waves.

-Chuck Harris

William Donzelli wrote:
(Tom Bruhns) wrote in message om...


Lots of discussion about using the 829 for VHF power amplifiers, and
even audio amplifiers and conversation pieces. But I haven't seen
mention here of their use in pulse generators.


Or CRT drivers (in the AN/APS-44 aircraft radar, and I think some of
the Navy PPI repeaters).


Perhaps someone knows: was the 3E29 an 829 re-designed and/or
specifically tested for use in pulsers?


Probably. 3E29 was used in the Mk III IFF interogators, circa 1943. I
don't know of any other major uses for the 3E29 (AKA 829A). Real 3E29s
are getting quite scarce, but 829Bs still can be found in biblical
quantities.


What was the 829 originally
intended for, and when was it first introduced? Who made the first
ones, RCA or someone else?

Hi,

The 3E29 may share a similar appearance, and the same pin out as the
829, but it certainly is not interchangable. To quote the RCA TT5
manual:

3E29: Heater-cathode type containing two high-perveance units used
as retangular-wave pulse modulator. Modulator Service maximum
CCS plate dissipation (per tube) 15watts.

Further down, it shows the plate supply voltage as 5000V, and the
instantaneous plate voltage as 5750V.

829: Heater-cathode type having midtapped heater used as af power
amplifier and modulator and as rf power amplifier and oscillator.

CCS dissipation is shown as 30W with natural cooling, and 40W with
forced air cooling.

It is pretty clear to me that the 3E29 was rearranged for high plate
voltage, and was used as a radar modulator tube. It is designed to
put out high voltage square waves.

-Chuck Harris

William Donzelli wrote:
(Tom Bruhns) wrote in message om...


Lots of discussion about using the 829 for VHF power amplifiers, and
even audio amplifiers and conversation pieces. But I haven't seen
mention here of their use in pulse generators.


Or CRT drivers (in the AN/APS-44 aircraft radar, and I think some of
the Navy PPI repeaters).


Perhaps someone knows: was the 3E29 an 829 re-designed and/or
specifically tested for use in pulsers?


Probably. 3E29 was used in the Mk III IFF interogators, circa 1943. I
don't know of any other major uses for the 3E29 (AKA 829A). Real 3E29s
are getting quite scarce, but 829Bs still can be found in biblical
quantities.


What was the 829 originally
intended for, and when was it first introduced? Who made the first
ones, RCA or someone else?

For the 829B picture and some "Beautiful Tube Pin-ups " SEE URL:


http://www.dogstar.dantimax.dk/tubes...ups/pinups.htm


--
73- Cambio - Keyboard To You (:-)
"Bill Turner" wrote in message
news
On 8 Feb 2004 21:44:55 -0800, (William Donzelli) wrote:

but 829Bs still can be found in biblical
quantities.

__________________________________________________ _______

Now there's a picture! Made my day.

--
73, Bill W6WRT

For the 829B picture and some "Beautiful Tube Pin-ups " SEE URL:


http://www.dogstar.dantimax.dk/tubes...ups/pinups.htm


--
73- Cambio - Keyboard To You (:-)
"Bill Turner" wrote in message
news
On 8 Feb 2004 21:44:55 -0800, (William Donzelli) wrote:

but 829Bs still can be found in biblical
quantities.

__________________________________________________ _______

Now there's a picture! Made my day.

--
73, Bill W6WRT

Chuck Harris wrote:
in rec.radio.amateur.boatanchors40283c62$0$3200$61fe ,

: Hi Ross,
:
: It certainly could be that they are very similar inside.
: I have used the 829B, but I have never had my hands on a 3E29.

Ditto. (Well, I haven't actually *used* them yet - they're still NIB! :-)

: Purely speculation on my part, but I would guess that the 3E29 has
: fewer sharp edges inside to help prevent arc over and other funny
: stuff at the 6x increase in plate voltage. I would guess that the
: cathode is made of much sterner stuff, and the vacuum is purer.

I have seen mention of harder vacuum and tolerances in pulse-rated tubes.

Ned, in a 1997 r.a.t post, compares a pulse-rated 4PR65A to a 4-65A, itself
already having a higher vacuum than your average receiving tube, and notes
that the latter wouldn't sub for the former. [http://tinyurl.com/3c5wx]
Elsewhere he mentions 4-400A and 4PR400A. Eimac numbers, I think.

: They make a special point of saying that the 3E29's mu will always
: be within 10% of the spec'd value. That tends to indicate that more
: care was taken with internal tolerances, particularily cathode to
: control grid spacing.

Quite possibly. I hadn't heard the 10%. Top of the bell curve selection?

: The part I find odd is usually when RCA is listing a similar tube
: they will say something like plate curves match 6L6, or some such.
: There is a total absence of mention of the 829B in the 3E29 spec
: sheet.

Exactly my point with the 6146 equivalent examples, all from TT5.
All listed as sharing 6146 data except for that very alike pulse tube 6293.

Yet, again, the ARRL Handbook data section has 3E29/829B sharing.

That German audio retailer with the Chinese amps has them using 829B, 3E29,
or GU-29, implying AF similiarity. There's a clear picture of the GU-29 at:
http://ly1dq.hypermart.net/gu-29.htm (and a simple 2M TX example at
http://ly1dq.hypermart.net/exam/gu-29_01.gif , to stay slightly on topic:-)

: What do you want to bet that the 3E29 also cost 3x the 829B?

(:=}) Quite possible, since military or other radar the likely application.
Plus it likely wouldn't do to say "Just use our 829B, it'll work fine" ;-)

They must have at least been "selected" or perhaps built to better specs.

It wouldn't make sense to be building an essentially identical tube too
differently. A subtly different cathode coating, perhaps, for the different
pulse current requirements? (like starting batteries vs storage) (total
speculation on my part!) and a longer time on the vacuum pump would be easy
to arrange on the same production line, with the build otherwise identical.
Perhaps harder vacuum plus statistical selection alone would be enough?

Ah! I've been scrolling through my files, and found some text on 829B/3E29
I'd saved from the Joenet archives (someone building an amp with one or two)
in which Gary Longrie says "Same tube, but the 3E29 is pulse rated, can hold
off 5kv, being built with ceramic parts."

I don't know how true this is ...

I notice that the UK mil CV2666 has a completely extra top mica disc above
the plates, extending all the way to to the glass, with ceramic inserts, as
well as the bottom metal disk with ceramic inserts like the RCA 829B.

It just occurred to me to do an image search on 3E29. Sure enough,
http://www5b.biglobe.ne.jp/~tritium/rca3e29-1.jpg
http://www5b.biglobe.ne.jp/~tritium/rca3e29-2.jpg
http://www5b.biglobe.ne.jp/~tritium/rca3e29-3.jpg

http://home.snafu.de/appelt/tubes/3E29.jpg

It looks the same as the RCA 829B that I have here, as far as I can see.

Hmm. http://hereford.ampr.org/cgi-bin/tube?tube=3E29
-
"Maximum Ratings (Design Center Values)

Plate Voltage ................................. 750 Volts
Grid No. 2 Voltage ............................ 240 Volts
Plate Dissipation ............................. 40 Watts
Grid No. 2 Dissipation ........................ 7 Watts

For other characteristics and typical operation, see 829B"
_

http://www.r-type.org/exhib/aaa0174.htm shows 829B (& "=" 3E29)

Commentary mentions the superior European double tetrodes, which

"made the 829B and 832 obsolete, and offered greater output power.
This valve type would not have been the valve of choice by 1950.
Currently, designs exist to use all of the VHF double tetrodes as audio
amplifiers, these are physically beautiful devices and deserve to be seen."

: Anybody have a 1950 price sheet?
:
: -Chuck Harris

That would be interesting, too.

RdM

[obviously with too much time on his hands right now, but likes his 829B!]

Chuck Harris wrote:
in rec.radio.amateur.boatanchors40283c62$0$3200$61fe ,

: Hi Ross,
:
: It certainly could be that they are very similar inside.
: I have used the 829B, but I have never had my hands on a 3E29.

Ditto. (Well, I haven't actually *used* them yet - they're still NIB! :-)

: Purely speculation on my part, but I would guess that the 3E29 has
: fewer sharp edges inside to help prevent arc over and other funny
: stuff at the 6x increase in plate voltage. I would guess that the
: cathode is made of much sterner stuff, and the vacuum is purer.

I have seen mention of harder vacuum and tolerances in pulse-rated tubes.

Ned, in a 1997 r.a.t post, compares a pulse-rated 4PR65A to a 4-65A, itself
already having a higher vacuum than your average receiving tube, and notes
that the latter wouldn't sub for the former. [http://tinyurl.com/3c5wx]
Elsewhere he mentions 4-400A and 4PR400A. Eimac numbers, I think.

: They make a special point of saying that the 3E29's mu will always
: be within 10% of the spec'd value. That tends to indicate that more
: care was taken with internal tolerances, particularily cathode to
: control grid spacing.

Quite possibly. I hadn't heard the 10%. Top of the bell curve selection?

: The part I find odd is usually when RCA is listing a similar tube
: they will say something like plate curves match 6L6, or some such.
: There is a total absence of mention of the 829B in the 3E29 spec
: sheet.

Exactly my point with the 6146 equivalent examples, all from TT5.
All listed as sharing 6146 data except for that very alike pulse tube 6293.

Yet, again, the ARRL Handbook data section has 3E29/829B sharing.

That German audio retailer with the Chinese amps has them using 829B, 3E29,
or GU-29, implying AF similiarity. There's a clear picture of the GU-29 at:
http://ly1dq.hypermart.net/gu-29.htm (and a simple 2M TX example at
http://ly1dq.hypermart.net/exam/gu-29_01.gif , to stay slightly on topic:-)

: What do you want to bet that the 3E29 also cost 3x the 829B?

(:=}) Quite possible, since military or other radar the likely application.
Plus it likely wouldn't do to say "Just use our 829B, it'll work fine" ;-)

They must have at least been "selected" or perhaps built to better specs.

It wouldn't make sense to be building an essentially identical tube too
differently. A subtly different cathode coating, perhaps, for the different
pulse current requirements? (like starting batteries vs storage) (total
speculation on my part!) and a longer time on the vacuum pump would be easy
to arrange on the same production line, with the build otherwise identical.
Perhaps harder vacuum plus statistical selection alone would be enough?

Ah! I've been scrolling through my files, and found some text on 829B/3E29
I'd saved from the Joenet archives (someone building an amp with one or two)
in which Gary Longrie says "Same tube, but the 3E29 is pulse rated, can hold
off 5kv, being built with ceramic parts."

I don't know how true this is ...

I notice that the UK mil CV2666 has a completely extra top mica disc above
the plates, extending all the way to to the glass, with ceramic inserts, as
well as the bottom metal disk with ceramic inserts like the RCA 829B.

It just occurred to me to do an image search on 3E29. Sure enough,
http://www5b.biglobe.ne.jp/~tritium/rca3e29-1.jpg
http://www5b.biglobe.ne.jp/~tritium/rca3e29-2.jpg
http://www5b.biglobe.ne.jp/~tritium/rca3e29-3.jpg

http://home.snafu.de/appelt/tubes/3E29.jpg

It looks the same as the RCA 829B that I have here, as far as I can see.

Hmm. http://hereford.ampr.org/cgi-bin/tube?tube=3E29
-
"Maximum Ratings (Design Center Values)

Plate Voltage ................................. 750 Volts
Grid No. 2 Voltage ............................ 240 Volts
Plate Dissipation ............................. 40 Watts
Grid No. 2 Dissipation ........................ 7 Watts

For other characteristics and typical operation, see 829B"
_

http://www.r-type.org/exhib/aaa0174.htm shows 829B (& "=" 3E29)

Commentary mentions the superior European double tetrodes, which

"made the 829B and 832 obsolete, and offered greater output power.
This valve type would not have been the valve of choice by 1950.
Currently, designs exist to use all of the VHF double tetrodes as audio
amplifiers, these are physically beautiful devices and deserve to be seen."

: Anybody have a 1950 price sheet?
:
: -Chuck Harris

That would be interesting, too.

RdM

[obviously with too much time on his hands right now, but likes his 829B!]

Chuck Harris wrote:

: The part I find odd is usually when RCA is listing a similar tube
: they will say something like plate curves match 6L6, or some such.
: There is a total absence of mention of the 829B in the 3E29 spec
: sheet.

Oddly, after all my previous post, I hadn't looked at an RCA 3E29 spec.
This old one (TT?) from 1946, does say " Similiar to type 829-B, but
intended particularly for pulse modulator service."
http://www.mif.pg.gda.pl/homepages/f...049/3/3E29.pdf

Still unclear on what makes the difference, though.