[ARC5] Quick sensistivity comparison

[J. Forster]

In my experience, just about all WWII vintage receivng tubes can benefit
from some gettering time.

I just put them in a tube tester, adjust the grid for the suggested plate
current, and lo9ck down the TEST button and go do something else for a day
or so.

-John

=================




> On 13 Jun 2013 at 4:45, J. Forster wrote:
>
>> Ken,
>>
>> It might be worth checking for gas in the tubes.
>
> In which? Do you mean the 12SK7s? Or in all?
>
>> I'd suggest running them for several days at nominal filament, nominal
>> plate, and biased to conduct about 10-20% of rated plate current to
>> allow the getter to clean up anything that has diffused into the tubes
>> in the last 70-odd years.
>
> OK. I can do that easily enough.
>
>> After that, try the NF test again.
>
> OK. Will do, John. Thanks very much for the suggestions.
>
>> YMMV,
>
> Yes! Won't it just! :-)
>
> Ken W7EKB
>
>