My vocabulary has increased today..........

Heres a brochure that shows some pinouts.
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Thanks to Cliff and Radiola Guy, I found the Hytronic Labs (Hytron) Engineering Bulletin on the "Bamtam Jr." line of miniature battery tubes dated March 1939. That explains why the late 1930s and early 1940s tube testers have sockets for them (including a few built into the 1950s). The tubes were probably not very successful. Interesting though. Frank's Data Sheets has some info on them. A search for the HY115 bought up a data sheet on all three (HY113, HY115, HY125). I think I have seen some of these numbers before either on the roll charts or supplements for my tube testers here. I will have to check.

I get these numbers mixed up with the line of octal based tubes with grid and plate caps that Hytron came out with for use in small 5 Meter and 2 1/2 Meters super-regenerative transceivers of the era for ham radio operators and others. Some of which were adapted and used in similar VHF and UHF war time radio equipment as well.

The data sheet (Frank's) gives operating potentials but not any pin outs. The 1939 Engineering Bulletin does give a pin out for the (2) pentodes but not the triode. Probably wouldn't be that hard to figure out the triode though. The pin out is not standard as we are used to for 5 pin tubes. I was just wondering about that in checking out the socket in my new Precision model 910 tube tester. The center or sixth contact in the bantam Jr. socket is used as one of two test points for checking out paper tubular and also mica capacitors for leakage in conjunction with the NE-31 neon short lamp (large G-10 bulb with candelabra base).


73, Rod WB6FBF

The only Bantam 5 pin tube I have ever seen was a projection lamp, strangely enough.
 Most of my old testers do have a socket for it though.

 Had to look for some CRT's for a couple of folks & found my I-177 in the storage trailer before my knee crapped out again. 30-40 trips up & down the ladder did me in.
 Pain pills & down for the day, at least.

One other mentionable, Heathkit models TC-1 & TC-2 had a socket for testing the (rather rare) 5 pin "[url=https://www.radiolaguy.com/images/flatwork/Hytron Bantam Jr.jpg]Hytron "Bantam Jr.[/url]" tubes. That socket was removed starting with model TC-3. Some of you have undoubtedly wondered what that small 5 pin socket was for and now you know.

Frank,
No. They are larger than that. Hence my joke about needing a large coat pocket to carry your hearing aid or radio in. I am familiar with the flat and round sub-miniature tubes although I don't have any at present. The Bantam Jr. tubes fit a small round socket. Larger than a 7 pin but smaller than a 9 pin miniature tube socket. The socket has a standard round 5 pin pattern with an extra pin in the middle of it for a total of 6 pins. I think most these tubes used the 5 pins and not the 6th. The pin size is comparable to those used on octal base tubes. Going back a ways to make a comparison, my guess is that they are bit smaller than a WD-11 or UX-199 tube but larger than a 215A tube.

Finding a matching 832 tube would be great to send to Robert to replace the broken one. We are having some light rain here. First time in a month.

73, Roderick  WB6FBF

Rod,
Are those the "pencil tubes" in it?
Glass and about the side of a pencil, they fit into an inline socket?

If so, probably have some in storage....someplace.....

RE: 832's
I might have one in storage. Mil, & the triangle stamp on it. Not sure if NOS or used.

Supposed to try to get in there tomorrow, if weather quits raining. I have to move over 2 cu yards out of the trailer to try find the CRT's a couple of folks want.

For the radio tube collectors out there: Any Bantam Junior or Bantam Jr. tubes in your collections? I read in the instruction manual for my new Precision 910 tube tester that such tubes were used in hearing aids and pocket radios (large coat pockets required?). Sockets for these small tubes are to be found in tube testers made in the 1930s and 1940s. Outside of seeing a picture of one in a book I don't think I have ever run across an actual tube anywhere. They are not to be confused with the line of GT, short metal shell, octal wafer based "Bantam" and "Bantal" tubes by Hytron and Raytheon. 

73, Rod  WB6FBF

I keep all of my tubes (maybe 100 to 180 ) in boxes and don't handle them at all.

I gave Frank a lot of tubes a couple of years back. He and I just sorted the ones most common to just regular radios. Then He got the rest, It's amazing to me his knowledge on what tubes are for what.

Anyway none of the ones I have have been tested yet. So they sit out in the bottom 3 shelves (Drawers) of My Huge VIDMAR cabinet in the garage.

Hmm, that is why it was a dud? Possibly gone to air with a leak at the plate electrode seal. The tap simply finished the job.
As a friend antique dealer would say. "it was its time"...

I have broken my share of tubes. My "one that got away" was a blue Arcturas AC-40. Laying on a "portable" display shelf, unnoticed. I mode the shelf, then noticed    as the blue tube rolled away just out of my grasp. Plonk, then "Ploop", the sound of old, soft tube giving its last gasp...

Chas

Hi Rod,

I do have a couple of spare duds. However, this one was unique for me as it had a U.S. Army stamp and a nice looking shield on the glass. My other ones don't have that. I will now be keeping my eyes open for an identical replacement. I still can't believe it broke the way it did. I barely felt the tap when it hit.

Robert,
I am sorry that happened but at least 832 tubes are still fairly common. A replacement shouldn't be hard to find or that expensive. The only use for them that I can recall was for the SCR-522 and SCR-274N VHF aircraft radio transmitters that were converted to 2 meter ham use after WWII. Fred M. Link used the 832's big brother in his line of FM taxi cab and police band radios, namely the 829 tube, and it was common to find it in the "final" amplifier in those type of rigs. Some time ago, I found that many of my Eimac style transmitting tubes sitting in boxes had bad stem press or grid-plate seals. It wasn't apparent they were full of air until filament voltage was applied and then watch the filament go up in smoke! 
73, Roderick  WB6FBF

By about a dozen new words! [You must be registered and logged in to see this image.]

Putting my tube back on the shelf and barely touched the pin sticking out at the top to the shelf above it. I heard a loud 'SNAP' then the tinkle of glass landing on the shelf. The only thing going for me is that the tube was a dud in my collection, but it was still part of my collection. [You must be registered and logged in to see this image.]