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previous: R.G. >Input impedance of FF is about hfe... -- 3/6/1998 8:42 AM

Re: Fuzz Face for the people!

3/6/1998 8:51 AM
MHelin	Re: Fuzz Face for the people! R.G. wrote: If only that were the case. As I understand it, the voltage feedback connection actually reduces the input impedance even more, as the voltage at the collector is 180 degrees out of phase and much larger. The effective input impedance of the VF stage is probably under 1K. I wrote a reply to my own post of the same subject, but isn't it so that the bypass cap changes things, as the feedback voltage no more strictly follows that of at the collector of Q1 due to the charging/discharging of the 22uF cap and the internal emitter resistance of Q2? -Mikko

3/6/1998 8:51 AM

MHelin

Re: Fuzz Face for the people!

R.G. wrote:

If only that were the case. As I understand it, the voltage feedback connection actually reduces the input impedance even more, as the voltage at the collector is 180 degrees out of phase and much larger. The effective input impedance of the VF stage is probably under 1K.

I wrote a reply to my own post of the same subject, but isn't it so that the bypass cap changes things, as the feedback voltage no more strictly follows that of at the collector of Q1 due to the charging/discharging of the 22uF cap and the internal emitter resistance of Q2?

-Mikko

Replies:

R.G. To the extent that it successfully ... -- 3/6/1998 9:32 AM