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How do I estimate cathode bypass capacitor voltage?

Hi all,

I'd like to learn how to calculate and select a safe voltage rating for the output stage of my next amp build. I have read a few posts, but I still don't seem to have it straight in my head.

The input stage is directly coupled to the 2A3 output stage. Output stage grid sits nominally at 152VDC, the cathode at 200VDC and the plate at 450VDC (bias -48V, plate to cathode 250V). Cathode R is 4,750 Ohm, bypassed to ground by the cathode bypass capacitor (not "Ultrapath").

How do I go about working out the required voltage rating? I assume it is not as simple as the VDC across the capacitor.

Please refrain from posts about the best "sounding" cap or capacitance, unless it is directly relevant to my question - I am interested in how to choose a cap with a safe voltage.

"Confusion of goals and perfection of means seems to characterise our age." Albert Einstein

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Topic - How do I estimate cathode bypass capacitor voltage? - 91derlust 18:34:45 03/18/17 (5)


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