Julian, G4ILO wrote: > > > > Bill Strong wrote: >> >> http://picasaweb.google.com/billstrong50/DigitalMaster780# >> >> This is a screen shot by KG3BOZ of my K2/100 running 50 watts on 40M >> PSK31. It shows IMD -23. This is a distance of about 1400 miles from >> Mississippi to Maryland at about 0100 UTC. My antenna is a Cobra >> Ultralite Senior up 20 feet. I tune it with the KAT100 and a big DXE >> balun. >> >> I usually run 20 or 30 watts but I wanted to see if I could run 50 watts >> mainly for use on 80M. If I blow a small fan on the heat sink the >> internal fan rarely comes on at 50 watts during converstaional PSK31. >> >> I use the Data Mode with the ALC set to light one bar. I transmit in the >> middle of the bandpass of the 2.2K SSB filter at 1000Hz. >> > I would think an IMD of -23dB is barely acceptable. (My KK7UQ IMD meter > defines "good" as better than -23dB.) However IMD measurements received > off-air by software are not reliable and often show poorer readings than > actual because the SNR is not good enough. Looking at the trace on your > screenshot I would have said your IMD was better than -23dB. >
Thanks Julian for the observation. I did not know about the inaccuracy although I did suspect over the air measurement might be different than in the shack. The best IMD I have seen on DM780 is about -27 with a super strong signal. I posted this because I thought it might be of interest to a newby like myself. It took me a while reading on the internet to begin to get a grasp of PSK31. Much of the best information has been on this forum. 73's Bill -- View this message in context: http://n2.nabble.com/K2-100%3A-PSK31-at-50-watts-Screen-Shot-tp2287875p2289131.html Sent from the Elecraft mailing list archive at Nabble.com. ______________________________________________________________ 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
