"Dave" wrote in message
news.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.


They are WWII military tubes. As you surmised, mostly for VHF
work. The smaller cousin was the 832B tube, used in the
SCR-522 transmitter (driver, PA stages). A very popular conversion
for 2-meter AM through the 50s and early 60s. The modern
version of the 829 is the 5894 power tube.


Pete

In article fmCUb.12231$gl2.8324@lakeread05, " Uncle Peter"
writes:

"Dave" wrote in message
tnews.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

They are WWII military tubes. As you surmised, mostly for VHF
work. The smaller cousin was the 832B tube, used in the
SCR-522 transmitter (driver, PA stages). A very popular conversion
for 2-meter AM through the 50s and early 60s. The modern
version of the 829 is the 5894 power tube.

The 829 was the final amplifier in the AN/TRC-1 and AN/TRC-4
VHF radio relay transmitter that was first fielded in Europe in 1943.
70 to 90 MHz, crystal controlled, phase modulation at a low
frequency, multiplied many times. Probably designed about 1941
but no data on that. Dual pentode with common cathode, plates
brought out to heavy pins on the envelope top. Pushed and
operating at maximums, it can put out about 75 W at 6 Meters.

TRC-1 and TRC-8 (high VHF) radio relay equipment was on 24/7
"hot spares" service for landline coupling backup at Army station
ADA in Tokyo up to 1954. Had literal hands-on with those. :-)
Those TRC-1 transmitters ran for hours and hours and hours without
fail, 40 to 50 Watts RF output.

A small tale on Lubriplate from Hank Kolesnik's mention in another
thread: The old radio relay equipment had separate receiver and
and transmitter cases and the TRC-1s had brushless shaded-pole
fan motors in the lids. While very cheap, those shaded-pole motors
are quite reliable. They have a (felt?) lubricant pad for sleeve
bearings; no appreciable load to require ball bearings nor high speed.

A well-intentioned newbie on one shift decided to "improve motor
performance" with Lubriplate (then a very new product in 1954) and
loaded the lubricant pads with it. While Lubriplate is a very good
product, it is a SLOW-SPEED thing. The shaded-pole fan motors
would seize up eventually, their normal light oil lubricant displaced by
the Lubriplate. For about three months it was SOP for all shifts to have
the "VHF man" check all the fans. Any fan with low or no flow meant
a bothersome job of removing the fan, replacing it with a spare, then
soaking the lubricant pad for several hours in solvent, saturating it
afterwards in the proper light oil, checking it out, keeping it as a
spare for the next stopped fan. Really put a kink in my magazine
reading on the night shifts...:-) Lubriplate is a fine lubricant for dial
drives and shaft bearings but should NOT be used in motor bearings.

Other than one incident with a blown fuse in one transmitter, the
dozen-plus AN/TRC-1s and TRC-8s ran and ran and ran reliably.

Len Anderson
retired (from regular hours) electronic engineer person

In article fmCUb.12231$gl2.8324@lakeread05, " Uncle Peter"
writes:

"Dave" wrote in message
tnews.com...
Hi all,

I just found several 829B tubes - believe it or not in my garage - I
must have got them in a box of stuff at a ham fest at one time.
A check on Ebay shows they're pretty much worthless for the sake
of dollars, but they're so COOL! With the two plate caps that are
actually just stiff pins, they look like little Martians.

They are WWII military tubes. As you surmised, mostly for VHF
work. The smaller cousin was the 832B tube, used in the
SCR-522 transmitter (driver, PA stages). A very popular conversion
for 2-meter AM through the 50s and early 60s. The modern
version of the 829 is the 5894 power tube.

The 829 was the final amplifier in the AN/TRC-1 and AN/TRC-4
VHF radio relay transmitter that was first fielded in Europe in 1943.
70 to 90 MHz, crystal controlled, phase modulation at a low
frequency, multiplied many times. Probably designed about 1941
but no data on that. Dual pentode with common cathode, plates
brought out to heavy pins on the envelope top. Pushed and
operating at maximums, it can put out about 75 W at 6 Meters.

TRC-1 and TRC-8 (high VHF) radio relay equipment was on 24/7
"hot spares" service for landline coupling backup at Army station
ADA in Tokyo up to 1954. Had literal hands-on with those. :-)
Those TRC-1 transmitters ran for hours and hours and hours without
fail, 40 to 50 Watts RF output.

A small tale on Lubriplate from Hank Kolesnik's mention in another
thread: The old radio relay equipment had separate receiver and
and transmitter cases and the TRC-1s had brushless shaded-pole
fan motors in the lids. While very cheap, those shaded-pole motors
are quite reliable. They have a (felt?) lubricant pad for sleeve
bearings; no appreciable load to require ball bearings nor high speed.

A well-intentioned newbie on one shift decided to "improve motor
performance" with Lubriplate (then a very new product in 1954) and
loaded the lubricant pads with it. While Lubriplate is a very good
product, it is a SLOW-SPEED thing. The shaded-pole fan motors
would seize up eventually, their normal light oil lubricant displaced by
the Lubriplate. For about three months it was SOP for all shifts to have
the "VHF man" check all the fans. Any fan with low or no flow meant
a bothersome job of removing the fan, replacing it with a spare, then
soaking the lubricant pad for several hours in solvent, saturating it
afterwards in the proper light oil, checking it out, keeping it as a
spare for the next stopped fan. Really put a kink in my magazine
reading on the night shifts...:-) Lubriplate is a fine lubricant for dial
drives and shaft bearings but should NOT be used in motor bearings.

Other than one incident with a blown fuse in one transmitter, the
dozen-plus AN/TRC-1s and TRC-8s ran and ran and ran reliably.

Len Anderson
retired (from regular hours) electronic engineer person