Hi Ron, As I replied to Don, I had a slightly different setup last year and did indeed eliminate the balun and feed it directly with my K2 (at the urging of both you and Don BTW). And it seemed to work great.
This year, I moved the antenna slightly higher and after researching some things on L.B. Cebik's site, I realized the feedline length of 33' put me at the half wave point for 40m. Since I had to lengthen it anyway, I went with the recommended 43' which was supposed to make it more of a multi-band use feed length. I'm kind of time strapped right now, but I would like to try this current config with my K2 and see if there is any difference in the way it tunes up. And then I guess I should play with different feed lengths to see if I can eliminate that balun. As I told Don, I should model this thing in EZNEC but I just haven't spent enough time with it to be comfortable with any results ;-) Thanks for the great info Ron. 73, Dave W8FGU > -----Original Message----- > From: Ron D'Eau Claire [mailto:[EMAIL PROTECTED] > Sent: Wednesday, July 02, 2008 1:02 PM > To: 'Dave Van Wallaghen'; elecraft@mailman.qth.net > Subject: RE: [Elecraft] OT: K3 and antenna questions > > No apologies needed Dave. Based on the posts here over the past decade, > your > question is *very* list-appropriate. > > Don's comments are "right on" as always. Any warming of the balun is RF > energy that was never radiated. At low powers, any noticeable heating is > likely a big chunk of your power. > > And a balun is completely unnecessary in most cases. > > About the reciprocity issue, keep in mind that almost *any* receiver has > plenty of gain to make up for poor antennas, where your transmit "gain" > (rf > power) is strictly limited. So almost any antenna will seem to "hear" much > better than it transmits. That's why on-ground and even underground > antennas > often do very well for receiving but are abysmal transmitting antennas. > > The big issue with receiving is usually signal-to-noise ratio. Your > transmitted signal is quite unaffected by local QRN, but your received > signal is terribly affected by such noise. (Again, that's why some use > on-ground or underground antennas for receiving. Local QRN is usually > attenuated much more at ground level than the signals arriving from > overhead, so such an antenna, while not providing as loud signals as a > true > "skywire" will often provide superior signal-to-noise ratios. The receiver > makes up for the overall lower gain and so often you hear signals much > better than with a skywire.) > > Ron AC7AC > _______________________________________________ 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
