[Test-Equipment] Sprague TO-6A question

[k4pf at juno.com]

Hi, Ken

Maybe V-4's grid bypass capacitor C-16 is itself leaky.
It is a molded paper type, according to the parts list.
I'd replace it with a .005 disc ceramic.

I don't have a Sprague TO-6, but do have a good TO-4.
On my TO-4, I replaced all the paper capacitors,
most of which were "Black Beauties".
Surprisingly, the 1952 vintage electrolytics were fine.

73,
Ed Knobloch

> Ken Kaplan <krkaplan at cox.net> wrote
I was trying to test some old 600v paper caps (Black Beauties, etc.) 
tonight and didn't see what I expected. 
I got nearly infinite insulation resistance. 
My really old caps (some from the 1940's) tested as good as 
some brand new caps I just bought. Hmm - maybe the TO-6 is faulty? I 
placed a 33 megohm resistor in parallel with a cap and it had no effect. 
I still had nearly infinite resistance. Then I tried it with a 1 meg 
resistor - same thing. I was using the L range and following the manual. 
<snip>