I spent some time measuring K3 power out vs. TUN PWR setting. I used a 60 MHz scope for power measurement and a dummy load that measures 1.06 SWR with the 10X scope probe connected. I did all measurements on 40M and I did these tests after conducting the power calibration procedure that is part of the Elecraft K3 utility.
In general I found plus or minus 5% agreement with the Tune power setting from 5 to 100 watts. With less than 5 watts power out the K3 seemed to have greater errors with more output power than requested. Worse case was 0.1 watts commanded with 0.16 watts measured. At 100 watts I measured 95 watts out, 5% low. I suspect +/- 5% is what I can measure with my equipment so I find good agreement. The measurements were very repeatable and I saw no evidence of power fluctuations on Tune power or later SSB tests. I looked at PEP power out at two commanded power settings (100 watts and 30 watts). PEP was a tad low but it is now the same as CW tune (my TXG VCE is +1 dB which I set based on these measurements). After looking at output in SSB I decided I could probably back my microphone gain off a bit. Perhaps I was pressing the number of ALC bars more than I needed to. There doesn't seem to be an advantage to pushing this. Details are in this table, I hope it renders properly. TUN Measured Error 0.1 0.16 58% 0.2 0.30 51% 0.3 0.46 52% 0.5 0.70 40% 1 1.2 16% 2 2.3 13% 5 5.1 1% 10 10.2 2% 12 12.1 1% 15 15.4 3% 20 19.8 -1% 30 30.3 1% 40 39.1 -2% 50 49.7 -1% 60 58.1 -3% 70 68.1 -3% 80 77.4 -3% 90 85.6 -5% 100 95.1 -5% Mike Scott - AE6WA Tarzana, CA (DM04 / near LA) K3-100 #508/ KX1 #1311 ______________________________________________________________ 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
