Re: Need help removing neg feedback from line stage.

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In Reply to: Need help removing neg feedback from line stage. posted by driver8 on March 16, 2006 at 06:05:21:

quick peek at scheme -
note - R14 and R15 (along with R19) form the feedback divider and inject nfb into the grid circuit from the plate's output.
you want to break the feedback loop but retain the 470K load from output cap plus retain 470 ohm output buffer resistor (sometimes chosen ~1/gm).
the end of grid resistor R15 formerly coming off ouput cap needs to tie to ground and 681K might be ok value.
a smaller grid-stopper than R14 (100k) could be helpful - maybe 10k.
try to understand the circuit before doing anything.

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Follow Ups Full Thread

Topic - Need help removing neg feedback from line stage. - driver8 06:05:21 03/16/06 (6)

Thanks for all the feedback. - driver8 08:07:08 03/20/06 (0)

AS a first try... - Allen Wright 03:43:53 03/17/06 (2)

need clarification - driver8 11:34:54 03/17/06 (1)

Re: need clarification - Allen Wright 02:44:40 03/19/06 (0)

Re: Need help removing neg feedback from line stage. - freddyi 13:21:17 03/16/06 (0)

Re: Need help removing neg feedback from line stage. - freddyi 10:37:43 03/16/06 (0)

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Re: Need help removing neg feedback from line stage. - freddyi 10:37:43 03/16/06 (0)

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