On 2/28/2012 2:22 PM, Jim Bennett wrote: > > I get TWO SWR > nulls. Yes, two. One is at 3.461 and has R=35, X-0, and SWR of 1.3. > The second null is at 3.654, R=0, X=1, SWR=1.0.
You have something seriously wrong, 0+j1 ohms is a short circuit, or extremely close to one. I'm sure the SWR reading at that point is bogus, the MFJ was not designed to operate into a short circuit. In fact, the apparent "short circuit" could be bogus, I've gotten some very improbable results a few times with my MFJ. I'd suggest: 1. Take your MFJ259 out to the feedpoint of the antenna and see what you get. 2. Put a dummy load at the antenna end of your coax run and measure the impedance at the shack end. It should be 50+j0 ohms everywhere [within reason] 3. Check the SWR with your K3 with the tuner in bypass at 3501 and up the band a few places and draw a graph of the readings. Keep the power down, you can't really hurt the K3, it'll quit making RF if it gets really annoyed. If the null at 3461 is really the resonant point of your antenna, you should see the SWR climbing rapidly as you go up the band. When really weird things happen in conflict with known physics, it's almost always a simple error in the system or measurement configuration. I'd look carefully at the wiring. Let us all know what you find, I'd like to write it into my notebook for future ref. 73, Fred K6DGW - Northern California Contest Club - CU in the 2012 Cal QSO Party 6-7 Oct 2012 - www.cqp.org ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:Elecraft@mailman.qth.net This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
