On Sun, 13 Jul 2003 23:50:42 -0400, "Ed" wrote:

Hi,

I recently aquired a "De Forest Audion 566". The box had "566 (866)"
written on it. I can't find any data on the 566 or whether it would be
reasonable to substitute the device in a circuit which calls for a 866A.

Any assistance would be appreciated.

Thanks !

Ed


The 866A is a half-wave mercury rectifier used in transmitters,
modulators, and similar equipment. It's rated 10,000 volts PIV and
0.25 amps average.

The tube is in a large ST-shaped package with a large plate cap and a
four-pin base. Height is 6 9/16 inches including pins and plate cap.
The diameter at the shoulder is 2 7/16".

You can usually see small drops of mercury clinging to the inside of
the glass. Does this sound like your 566?

At these power levels, I would not suggest substituting one tube for
another unless your ABSOLUTELY SURE that the sub is correct in your
particular application.


73 de Leigh W3NLB