On Mon, 2007-09-10 at 22:22 -0400, [EMAIL PROTECTED] wrote: > Was that the one in the ARRL Handbook around 1958 - 1961?
The keyer described earlier sounded different than the one in the handbook in that it had a monitor and didn't self complete.. I built the one in the handbook and used if for many years. It had one sawtooth generator and it oscillated at different frequencies, one for dashes and one for dots. The other half of that 12AU7 was the rectifier tube. The other 12AU7 formed the clipping circuit that clipped the tops off the sawtooth waves and drove the keying relay. Actually, half of that tube clipped the sawtooths the other half set the clipping level -- essentially the keying weight. There was no monitor circuit or speaker in that design. Also it did, as you point out, self complete each dot or dash. It was a cool design and I used it in many a Sweepstakes and CD party. I also built the 4-400 amp and a 6C4 based TR switch out of the same issue of the handbook. It was the 1961 Handbook although I was using it in 1965 and later. Man, that was a long time ago.. 73, -Doug, W7KF _______________________________________________ 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
