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previous: Ed Howard-I know how the circuit w... -- 5/13/2004 5:16 PM

Re: Switching the larger cap in parallel is better?

5/13/2004 7:40 PM
Howard	Re: Switching the larger cap in parallel is better? With the switch open, at DC the big cap will pass no current so the impedance of the branch Zb = (47K -jinfinity) = infinity, so the voltage drop I^2R across the 47K resistor is zero. The big cap sees the same voltage as the little cap and no current flows when the switch is closed. At AC, the impedance is (47K - j(1/2pifC) )At 60 Hz that's (47K - j106). So as far as the 820 ohm cathode bypass resistor sees, this branch is an open circuit. Well, that's my theory.

5/13/2004 7:40 PM

Howard

Re: Switching the larger cap in parallel is better?

With the switch open, at DC the big cap will pass no current so the impedance of the branch Zb = (47K -j*infinity) = infinity, so the voltage drop I^2R across the 47K resistor is zero. The big cap sees the same voltage as the little cap and no current flows when the switch is closed. At AC, the impedance is (47K - j*(1/2*pi*f*C) )At 60 Hz that's (47K - j*106). So as far as the 820 ohm cathode bypass resistor sees, this branch is an open circuit.

Well, that's my theory.