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Old 07-02-2019, 11:29 PM
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Quote:
Originally Posted by Yamamaya42 View Post
yes, its at 147 v DC still and when i hooked a o-scope i saw a 13 volt wave there left side of c135
Cathode @ 6v , grid @ -86v with 240v waveform


edit
r203/204 new and V21 new.
As you are getting a good blanking pulse, my bet is that the designers expected the variation in the range you are seeing and determined that the circuit would still work properly with this variation.

Edit: if you have extra tubes, it might be educational to plug a few in and see if the DC changes but the pulse is still OK. If you don't have extras, you could still experiment by exchanging V21 and V20.
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