Unknown mini triode

Hello everyone,

I have two small triodes in my possession of which I know nearly nothing. Experimentally it appeared that the filament voltage was about 6.3 V. That is all I know. There is no marking to be seen on the glass envelope, so I am totally in the dark.

Anyone have any ideas?

Regards,
Sander Stols

• Unknown mini triode (37 KB)
• Unknown mini triode (46 KB)
• Unknown mini triode (49 KB)

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The tubes look very like to the 955 UHF triode.

Regards

Dietmar

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Thank you Dietmar Rudolph for your very quick answer! I think you are right: it looks very much the same. The glass envelope is frosty so it is nearly impossible to see anything inside. And the red top seems to be on the outside, so it is probalbly not original.

Regards,

Sander

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Sometimes called "Acorn" valves.

I tested an RCA 955 a couple of weeks ago (loaned) on my newly built uTracer. It looks identical. Of course there are a number of similar devices in that package. I just uploaded the curves to the 955 page (click on "more" on Characteristics).

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