This tester uses regulated power sources for the bias, plate, & screen voltages, as well as modified operating & testing procedures.

Filament voltage is also controlled. 

Tubes are tested in accordance with the manufacturer's specifications; measurements closely align with a laboratory tester built to rigorously measure vacuum tube characteristics. 

Tubes can be accurately matched for gm & plate current at the manufacturer's specified test points or at other specified test points.

***** This tester was prepared by Mr. Paul Hart of Falls Church , Virginia. *****

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Industry Bogey transconductance =  5900/5900 µmhos  & 

Industry Bogey plate current =  10.0/10.0 mA

Results = 

5500/4200 µmhos  ~   9.8/7.9 mA

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