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Old 05-04-2019, 09:43 PM
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Join Date: Jul 2004
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Sawtooth on cathode is normal.

Back of envelope without using exponentials: Average current is 1 ma (40v/39kohms). This is supplied in a narrow pulse of, say 2.5 microseconds, or 1/20 of the horizontal rate. So, the peak current is 20 ma for 2.5 microseconds, = 50 nanocoulombs. This causes a rise of 5 volts on 10 nF C98.
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