Bob Pease would be proud!!! That is a really cool application - not to mention you taking time to explain it. 73s, Pete > > From: wayne burdick <[EMAIL PROTECTED]> > Date: 2007/03/10 Sat AM 12:03:56 CST > To: [EMAIL PROTECTED] > CC: [email protected] > Subject: [Elecraft] Re: sidetone mod now works (RP5, etc., explained)
> There's some subtlety to this circuit. Among the various goals was to > minimize component count. > > C32, on pin 8 of U9, is the AF amp's supply decoupling capacitor. It > would normally be returned to ground, as shown in any LM380 datasheet. > However, we played a trick here, using pin 8 as the sidetone injection > point. In other words, we're treating pin 8 as a low-gain, single-ended > third input to the amplifier. > 73, > Wayne > N6KR > > > --- > > http://www.elecraft.com > > _______________________________________________ > Elecraft mailing list > Post to: [email protected] > You must be a subscriber to post to the list. > Subscriber Info (Addr. Change, sub, unsub etc.): > http://mailman.qth.net/mailman/listinfo/elecraft > > Help: http://mailman.qth.net/subscribers.htm > Elecraft web page: http://www.elecraft.com > Pete Axson WD4LST 17901 NE 18th Ave Citra, FL 32113 _______________________________________________ Elecraft mailing list Post to: [email protected] You must be a subscriber to post to the list. Subscriber Info (Addr. Change, sub, unsub etc.): http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/subscribers.htm Elecraft web page: http://www.elecraft.com
