First use of long stored tubes.

This is an AGING instruction,
not Rejunivation instruction.

 

here is an old instruction of how to start using very long stocked tubes, translated by someone from a Chinese document. Sorry for the bad English. This instruction looks made by experienced people, and I see only good things written in there.

Still no guarantee that this is the right way!

Before using new electron tube or reusing the tube that has been stored very long, please age it.

1. Before putting any electrical signal on it, the electron tubes should warmed up at 45°C for 20minutes, to make sure there is no humidity inside the socket any more. When the tubes were stored in a dry, warm place, this step is not necessary. When the tubes was stored below 15°C, this step must be done.

2. When electron tube is in service, parameters that reach usage limits should be not more than one. For instance, when you use maximum voltage, do not use maximum dissipation at the same time.

3. Filament voltage should be brought to the rated voltage moderarely slow. While measuring current. Make sure Filament starting current should not more than 150%. Its voltage should be measured precisely and the alteration should not more than 2%. Now check if rated current is same as in datasheet. When too high, the tube vacuum is suspected.

Filament under half voltage should now be aged for 10-15 minutes. Next step is under full voltage should be aged for 30 minutes. No other voltages should be applied.

4. When the tube is under static aging with high voltage, the rated anode dissipation should not more than 60%. Observe if anode current stays the same, or will increase moderately. When anode current increases, adapt grid voltage to keep anode current at 60%.

5. When previous step was succesfull, normal working condition can come now. Observe if anode current is stabile. When anode current changes, observe carefully and adapt settings. No parameter should be over the usage limit.

Note for steps 4 and 5: When anode current will go down slowly, do not continue, or tube will damage. This problem may be solved by an experienced person.