• WARNING: Tube/Valve amplifiers use potentially LETHAL HIGH VOLTAGES.
    Building, troubleshooting and testing of these amplifiers should only be
    performed by someone who is thoroughly familiar with
    the safety precautions around high voltages.

Tube labeld ETBB

Best photo I can get...


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Sadly the pix don't help much. You'll need to trace out the electrode connection to each pin and once you do that you can then test them to see what type they test closest to..

They appear to be dual somethings.. :D

Edit: As best I can make out there is a shield between the sections, and I can make out what appears to be a single grid in one of the sections, but I cannot make out much more detail than this. I can't make out the filament either. I'll swag though that it is somehow related to the other tubes that came in that box, and might be a 12A_7 family tube..
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Looks like ET88.
E denotes heater voltage (6v3). The second letter denotes function, "T" means "miscellaneous". The decade numeral is the base type, 8 being B9A. And the last digit is the specific variety. High numbers here would be uncommon - except in types where there is a lot of room for variation (triodes and pentodes) - one might expect to see lots of ET80 or ET81 before seeing an ET88

However, in all my books I can find but ONE valve with an ET prefix - a submin wire ended type.
The pictures look very much like an ECC85 - a screened RF triode for VHF front ends.
Better photos would help.

You've got an Olympus D-520 zoom camera. On the back there is the four-way cursor pad. Look for the little icon that resembles a flower (it's near the up button). That should put your camera into macro mode. Do not use any zoom when in macro mode - keep it at 1x (wideangle). That camera should be able to focus properly as close as 8" when in macro.