I.D. This Tube?

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kraml
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I.D. This Tube?

Post by kraml »

Anyone able to I.D. this large tube? Quite certain it's "worthless" but would be interesting to know what it is. At least I could test it then. It's being scotched by another worthless guy.
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Stevem
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Re: I.D. This Tube?

Post by Stevem »

Well it looks like it’s a duel section Octal, with one rectifier section and what looks like one Triode section .

Any more then that I don’t know how one would figure that out!
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Not screaming like the passengers in his car!

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Phil_S
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Re: I.D. This Tube?

Post by Phil_S »

I like a good challenge. I like what Stevem suggests. If we knew more, we might be able to find a picture. There are a couple of museum type websites for vacuum tubes that have pictures and eBay is another source of pictures. It is possible to develop a list of double diode + triode tubes. The list might be expanded for tubes with 2 configurations inside.

Museum picture example:
https://www.radiomuseum.org/tubes/tube_6sq7gt.html
eBay example:
https://www.ebay.com/itm/Delco-GM-Vinta ... 3534590736

Do you know or do you have any idea what device that tube came from? I'm thinking an old car radio. What I'm driving at is the heater voltage requirement. If we know it is 6.3V or 12.6V it narrows the choices. And/or, is there any way to identify which pins are the heater pins? This might be done by simple observation of where they go at the bottom of the glass tube. The pictures don't show this and I'm not sure you could easily get one. When we know the heater pins, we can narrow the base configuration. For example and 8Q Octal will have heaters on pins 7 and 8. This will narrow the choices further.

We know it is a glass tube, so we can eliminate all the metal tubes. We can eliminate those with a top cap. We can also eliminate tubes that have curved glass. It's a start.

Here's a long shot. Put the tube in the freezer for a while. When you remove it, breathe on the glass so moisture will condense on the glass. Sometimes this will reveal the tube type mark...problem solved.
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didit
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Re: I.D. This Tube?

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Phil_S
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Re: I.D. This Tube?

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