G1 short in a 21FBP22

[IsthmusTV]

JR and Old TV Nut,

Thanks very much for the help. I guess I should have realized what was going on (basic vacuum tube theory). But what I don't understand is why the CR-70 indicates a short in this instance. I believe that it just functions as an Ohm meter measuring the resistance between the cathode and G1 in the "G1 shorts" function. You'd think that this method would yield a lot of false positives because of the diode action. Maybe the cathode and G1 are unusually close together in this case. Anyway, I'm glad that it doesn't make the tube unusable. Now if I can just get the emissions up on all three guns...

-Clark