hickok: Specific Procedures to test early C- series tube

ID: 79352
hickok: Specific Procedures to test early C- series tube 
01.Dec.05 01:54
2195

Robert Sarbell † 22.3.22 (USA)
Articles: 363
Count of Thanks: 5
Robert Sarbell † 22.3.22

I have a minor problem which may be due to the limitations of my tube tester, a Hickok 752A.

I have made some adapters to allow me to test the older European tubes - and I have been quite satisfied with the results up to the last few days. I have had essentailly no significant problems testing the majority of the tubes that I created the adapters for - St8 or P8A, and the Au8 (octal side-pin), and the Rimlock tubes. I have even been satisfied testing some RV12P2000 tubes using an "early US 6-pin adapter" that I made.

I have been able to correlate most of the data from the RMorg tubes data, and from
the Funke W19 cards (I have a complete set). And have also received some assistance from Herr Birkner which may be instrumental is solving my dilemma.

But, I seem to have hit a "roadblock" with the early C-series tubes.

I believe the problem may be attributable to the type of potential supplied (AC/DC) for the plate, screen, and signal voltages, as well as the 0.2A required for these tubes.

The filament voltage selection on the 752A tester offers only 25.0v or 35.0v - I had considered the 26-33v between the CL2 and CL4 tubes, with 29volts preferred for typical operation. I have elected to choose the 25.0v filament setting (I would prefer not to use the 35.0 volts, unless the slight additional potential would do no harm to the filament).

I get no observable deflection of the needle on the tester . . . .using any of the X scale factors (1,2,4, or 10)

Comments or observations would be most appreciated.

Respectfully,
Robert
NOTE: These tests are being conducted to restore the Philips AL161 which I believe uses these tubes!

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