Hi Ed, I have also high SWR (up to 3:1) on my K3 on 20 mts when the amp is operating. IN the Powermaster it show a 1.5:1. When the amplifier is in Standby the SWR on the K3 was 1.5:1, so something bad when the amplifier is running.
I need to do another tests, but your email took my attention. 73, Jorge CX6VM/CW5W K3 #4077 -----Mensaje original----- De: [email protected] [mailto:[email protected]] En nombre de Edward R. Cole Enviado el: Martes, 20 de Marzo de 2012 04:16 p.m. Para: [email protected] Asunto: Re: [Elecraft] How accurate is the K3 SWR meter Just a Post Script (or Note) to the discussion: I was seeing high SWR using my K3 to drive my new 300w HF amplifier, with amp bypassed and QRO tuner (that follows the amp) switched directly to dummy load. This was on 20m. I have the K3 ANT1 (no internal tuner) connected to a MFJ tuner and then thru the 150w Mirage 6m amp and then to the HF amp. DPDT TR relay. The 6m amp bypasses when powered off. Well the solution was removing the 6m amp from the path. Some ham equipment is not well designed for other frequencies it appears! MY SWR went from 1.8 to 1.1 with this simple change. Actual input SWR when driving the HF amp is about 1.4 but the bypass thru the TR relay shows no impedance issues as the 50-ohm dummy is seen by the K3 with no "bump". Since I have a MFJ945E tuner follow the K3, I have two SWR indications to observe and I do often see a difference in indication if the SWR is high. Once the MFJ tunes out any SWR they agree. I have to use a tuner on my triband yagi (very old), but my 80/40m inverted-V is resonant so tuners are not needed. HF amp input matches better at lower freq. bands, though the K3 has no trouble at any band with driving the amp. The Drake MN2000 was added when I installed the new HF amp since it can run up to 2kW. It makes sure the amp sees a good load and also gives me a monitor for the amp output. Summarizing: Check every part of your system from K3 to antenna; you may find some surprises! Always check coax line by line! 73, Ed - KL7UW, WD2XSH/45 ====================================== BP40IQ 500 KHz - 10-GHz www.kl7uw.com EME: 50-1.1kw?, 144-1.4kw, 432-QRT, 1296-?, 3400-? DUBUS Magazine USA Rep [email protected] "Kits made by KL7UW" http://www.kl7uw.com/kits.htm ====================================== ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html ----- Se certifico que el correo no contiene virus. Comprobada por AVG - www.avg.es Version: 2012.0.1913 / Base de datos de virus: 2114/4882 - Fecha de la version: 20/03/2012 ______________________________________________________________ Elecraft mailing list Home: http://mailman.qth.net/mailman/listinfo/elecraft Help: http://mailman.qth.net/mmfaq.htm Post: mailto:[email protected] This list hosted by: http://www.qsl.net Please help support this email list: http://www.qsl.net/donate.html
