--- Don <[EMAIL PROTECTED]> wrote: > At the moment, though, I am having trouble coming up with a software > algorithm that finds minimum swr and this message is a request for > suggestions. > .... > Any ideas?
Hi Don. Most tuners contain directional couplers to indicate VSWR, but they are often sandwiched between the transmitter and the tuning network. The tuning network is then adjusted for zero reflected power using a trial-and-error approach. If the directional coupler were instead placed between your tuning network and the antenna jack (the OUTPUT of the tuner), you could use the amplitude and phase information returned from the coupler to determine the complex impedance of the load (antenna) you wish to match to 50 ohms. Next, you could calculate what conjugate impedance the tuner needs to place in series with antenna jack to produce the 50 ohm resistive output impedance you desire, and then select the appropriate L and C values in your tuner network to produce that impedance. Done! 73, de John, KD2BD Visit John on the Web at: http://kd2bd.ham.org/ . . . . __________________________________ Yahoo! Mail - PC Magazine Editors' Choice 2005 http://mail.yahoo.com _______________________________________________ Elecraft mailing list Post to: Elecraft@mailman.qth.net 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