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Vintage threads from the first ten years

Re: Advanced feedback loop questions..

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11/5/1999 2:27 AM
John Stokes	Re: Advanced feedback loop questions.. Dave to get books that go into NFB in detail, you'll probably have to get some college level engineering textbooks. How's your calculus? It gets DEEP in the math real fast. Control systems classes....ugh...you bring back nightmares.

11/5/1999 3:40 AM
David Manson	geez -- i hate calculus..

11/5/1999 8:34 PM
Don Symes	Any circuit that involves a cap or inductor is a hardware realization of a differential or integral equation. Not that I like it any better ;-[

11/5/1999 11:27 PM

I have a UK booklet I bought in xerox years back all about -fb loops.. nyquist plots and the whole thing.. written in english too.. I'll scan it up and make a *.pdf this w/e hopefully. It's quite helpfull as far as understanding the concepts, simple equations, etc etc. It goes deep without getting too calculus heavy.
I'll let you know when it's up and where to DL. maybe it will help.

other than that, the RDH has good stuff about -fb, pphase gain etc etc.

my one rule of thumb is that you can always (ideally) use LESS -fb, but you can get into deep yogurt using MORE.

11/6/1999 4:33 PM
Dave Stork	Speedo wrote: my one rule of thumb is that you can always (ideally) use LESS -fb, but you can get into deep yogurt using MORE. Yes, with a typical tube amp, it's generally safe to use less feedback. But solid state amps are a different matter. Many will become unstable if you try to run them open loop.

11/5/1999 11:44 PM
SpeedRacer	I have a UK booklet I bought in xerox years back all about -fb loops.. nyquist plots and the whole thing.. written in english too.. I'll scan it up and make a *.pdf this w/e hopefully. It's quite helpfull as far as understanding the concepts, simple equations, etc etc. It goes deep without getting too calculus heavy. I'll let you know when it's up and where to DL. maybe it will help.

11/5/1999 12:56 AM
David Manson	If you take the signal back 2 gain stages it would be a positive feedback loop? and whats LFO? I'm still kinda new at this..

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