Mike, I see the same thing. My Autek says my antenna is 2.5:1, the K3 (#476) says 1.2:1 at the same frequency (numbers mentioned were on 40M).
My Palstar SWR meter pretty much agrees with the Autek. -Jeff N6GQ On Thu, Jan 1, 2009 at 17:47, Mike Scott <[email protected]> wrote: > I have been working on antennas today and have a puzzle. I am finding that > the K3 SWR indications are unbelievable generous. > > With my 40M inverted V fed with RG8X (50 ohm) coax I see that the K3 seems > generous in the SWR indication on tune with ATU bypassed. I have noticed a > slight change in SWR with K3 power setting so the following was taken with > K3 tune power set to 100 watts. If I set it to 10 watts the discrepancy is > greater... > SWR SWR SWR > Freq. K3 VA1 Daiwa > 7.00 MHz 1.3 1.92 2.0 > 7.05 MHz 1.2 1.92 1.9 > 7.1 MHz 1.2 1.98 1.95 > 7.15 MHz 1.3 2.26 2.1 > 7.2 MHz 1.9 2.60 2.3 > 7.25 MHz 1.5 2.88 2.6 > 7.3 MHz 1.6 3.32 2.7 > > The Daiwa is the CN-101L cross needle meter. The VA1 is the Autek Rx Vector > antenna analyzer. The VA1 does not have a tuned input so it is possible > that it can be fooled by local broadcast stations. I don't suspect this > issue here as there aren't any close by broadcast stations that I am aware > of. The Daiwa and the VA1 tend to agree pretty well anyway. The K3 > measurements are the outliers. This antenna on a "Tenna Dipper" shows > minimal SWR at 7.040 MHz, just where I tuned it a few years ago. The LED > does not extinguish indicating higher than 1:1 SWR at the minimum. If you > look at the numbers, I guess I don't believe the K3, Do you think my antenna > is below 1.6 to 1 across the entire 40M band? > > > So now on to 20M dipole fed with RG58 (50 Ohm Coax)... > The Tenna Dipper fully extinguishes at 13.805 MHz indicating that my antenna > is bit too long but is close to 1:1 at that frequency. > > Freq K3 VA1 Daiwa > 13.81 -- 1.12 -- > 14.0 MHz 1.1 1.24 1.31 > 14.1 MHz 1.1 1.30 1.70 > 14.2 MHz 1.1 1.55 1.85 > 14.3 MHz 1.2 1.69 1.85 > > RG58 may have some losses on this band so perhaps all of the SWR indications > are generous, some more than others. The dipole is a low one and probably > isn't 72 ohms at the feed point. > > Mike Scott - AE6WA > Tarzana, CA (DM04 / near LA) > K3-100 #508/ KX1 #1311 > > > _______________________________________________ > 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 > > _______________________________________________ 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
