• 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.

United Electronics 805 tube dating

I found a very large United Electronics 805 tube recently at an estate sale. (In good shape). I’m trying to identity and date it.
I understand these United tubes are USA-made WWII era. Is there any way to find out the year and place of production?
 
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