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previous: Charlie Does the guitars volume pot effect... -- 4/7/2000 5:39 AM

Re: Input impedence

4/7/2000 1:48 PM
J Fletcher	Re: Input impedence I think of the guitar pickup as an AC generator with an internal impedance of 10k or so. One side has to go to ground to complete the circuit. The top of the pickup is in parallel with the volume control and the 1 meg grid resistor. Most of the signal is dropped across this parallel network, since it's much higher in resistance than the 10k guitar pickup. Some will be dropped across the internal resistance of the pickup, but it will be a small amount. It might help to visualise the pickup as a battery connected to the volume control and the grid resistor. One side, negative, goes to ground, the other side, positive, to the top of the resistors. Current flows. Does that explanation make it better...or worse ?...Jerry

4/7/2000 1:48 PM

J Fletcher

Re: Input impedence

I think of the guitar pickup as an AC generator with an internal impedance of 10k or so. One side has to go to ground to complete the circuit. The top of the pickup is in parallel with the volume control and the 1 meg grid resistor. Most of the signal is dropped across this parallel network, since it's much higher in resistance than the 10k guitar pickup. Some will be dropped across the internal resistance of the pickup, but it will be a small amount.
It might help to visualise the pickup as a battery connected to the volume control and the grid resistor. One side, negative, goes to ground, the other side, positive, to the top of the resistors. Current flows. Does that explanation make it better...or worse ?...Jerry

Replies:

Charlie But isn't the the total impedence t... -- 4/8/2000 5:09 AM