Kenneth Scharf wrote:
On 08/13/2011 01:48 PM, Richard Knoppow wrote:

Among other applications sub-miniatures were used in
hearing aids and model aircraft controllers.


Subminiature tubes were developed as bomb fuses for use in mines and
torpedoes.

I think indeed the first subminis that came out of the Raytheon plant
were intended for proximity fuses. Those were designed with very heavy
reinforcement so they could handle heavy acceleration parallel to the
plate, and that same technology made them useful in a lot of other
low-microphonic applications.

Some of the last ones that came out of the plant were spares for the
first and second generation B-52 navigation systems, which used a
von Neumann machine made up of around 250 submini tubes.

In the meantime they went into everything from Army field radios to
weather balloons to condenser microphones.

They were just a hell of a great technology if you ask me.
--scott

--
"C'est un Nagra. C'est suisse, et tres, tres precis."

On Sat, 13 Aug 2011, Scott Dorsey wrote:

Kenneth Scharf wrote:
On 08/13/2011 01:48 PM, Richard Knoppow wrote:

Among other applications sub-miniatures were used in
hearing aids and model aircraft controllers.


Subminiature tubes were developed as bomb fuses for use in mines and
torpedoes.

I think indeed the first subminis that came out of the Raytheon plant
were intended for proximity fuses. Those were designed with very heavy
reinforcement so they could handle heavy acceleration parallel to the
plate, and that same technology made them useful in a lot of other
low-microphonic applications.

Some of the last ones that came out of the plant were spares for the
first and second generation B-52 navigation systems, which used a
von Neumann machine made up of around 250 submini tubes.

In the meantime they went into everything from Army field radios to
weather balloons to condenser microphones.

Not just military stuff. Those Motorola lunchbox type transceivers,
something like the P-33 (maybe that was a later model) used subminatures
in a hybrid. There were some consumer radios that used them. There was
even at least one military general coverage receiver that used them, I
can't remember the model but I remember the surplus ads, and it was quite
a fancy receiver (so likely the subminature tubes did make a difference
there, allowing it to fit into a somewhat reasonable space.

Michael VE2BVW

"Michael Black" wrote in message
ample.net...
On Sat, 13 Aug 2011, Scott Dorsey wrote:



Lots of snipping here...

Subminiature tubes were developed as bomb fuses for use
in mines and
torpedoes.

I think indeed the first subminis that came out of the
Raytheon plant
were intended for proximity fuses. Those were designed
with very heavy
reinforcement so they could handle heavy acceleration
parallel to the
plate, and that same technology made them useful in a lot
of other
low-microphonic applications.

Some of the last ones that came out of the plant were
spares for the
first and second generation B-52 navigation systems,
which used a
von Neumann machine made up of around 250 submini tubes.

In the meantime they went into everything from Army field
radios to
weather balloons to condenser microphones.

Not just military stuff. Those Motorola lunchbox type
transceivers, something like the P-33 (maybe that was a
later model) used subminatures in a hybrid. There were
some consumer radios that used them. There was even at
least one military general coverage receiver that used
them, I can't remember the model but I remember the
surplus ads, and it was quite a fancy receiver (so likely
the subminature tubes did make a difference there,
allowing it to fit into a somewhat reasonable space.

Michael VE2BVW

I think they were used in a couple of receivers made for
the Navy by RCA. I remember seeing the solder-in tubes
there. As Scott points out they were also used in some
miniature microphones, for instance the Altec-Lansing M-20
system (I have one somewhere).


--
Richard Knoppow
Los Angeles
WB6KBL

In article ,
Scott Dorsey wrote:
Kenneth Scharf wrote:
On 08/13/2011 01:48 PM, Richard Knoppow wrote:

Among other applications sub-miniatures were used in
hearing aids and model aircraft controllers.


Subminiature tubes were developed as bomb fuses for use in mines and
torpedoes.

I think indeed the first subminis that came out of the Raytheon plant
were intended for proximity fuses. Those were designed with very heavy
reinforcement so they could handle heavy acceleration parallel to the
plate, and that same technology made them useful in a lot of other
low-microphonic applications.

Some of the last ones that came out of the plant were spares for the
first and second generation B-52 navigation systems, which used a
von Neumann machine made up of around 250 submini tubes.

In the meantime they went into everything from Army field radios to
weather balloons to condenser microphones.

They were just a hell of a great technology if you ask me.

I think that the first Raytheon subminiatures were from 1938-39 and
made possible electronic amplifiers for hearing aids that could be
worn in a man's suit. Beltone and Sonotone were producing amplifiers
with these tubes that were about the size of a pack of cigarettes in
1940. The proximity fuse tubes were a ruggedized development of an
already-mature product made in quantity for a ready civilian market.

I don't know when Raytheon last made subminiature tubes, but do know
that they were going into new-manufacture missile warhead guidance
electronics until the early-mid 1970's.

Sonotone did have their own line for subminiature tubes, but I don't
know whether that was set up during WWII or afterward. Their first
"transistorized" hearing aid hit the market in 1953, but it was a
hybrid that still used tubes plus one transistor in a cigarette-pack
amplifier.

Hank

I don't know when Raytheon last made subminiature tubes, but do know
that they were going into new-manufacture missile warhead guidance
electronics until the early-mid 1970's.

Production line shut down in 1983, I think. That factory now only makes
magnetrons and travelling wave tubes.

Sonotone did have their own line for subminiature tubes, but I don't
know whether that was set up during WWII or afterward. Their first
"transistorized" hearing aid hit the market in 1953, but it was a
hybrid that still used tubes plus one transistor in a cigarette-pack
amplifier.

The Japanese made the things too, and there were other companies like Hy-Vac
making them.


BUT... as far as the original poster's tube goes, I got a couple from him
in the mail and it looks to be a pentode with a 5J pinout. My guess without
putting it on the curve tracer is that it is likely to be a CK531DX. I'll
try and test it more carefully this weekend.
--scott
--
"C'est un Nagra. C'est suisse, et tres, tres precis."