Mitch, Has your K3 had the modification described in <http://www.elecraft.com/K3/mods/ELECRAFT_Application_Note_Improving_the_Immunity_of_the_Rear-Panel_KIO3_RS232_and_Audio_Connectors_to_RF.pdf> performed on it - specifically, bypassing L1 as described at the top of p.4 of the application note?
I had serious noise pickup on the IF output from my K3, which pulsed in time with polls from my radio control software. The source was a USB-to-serial adapter connected to the K3's RS-232 jack. After I performed the above mod the problem disappeared. I did several other mods at the same time, so perhaps it wasn't this one that did the trick, but I suspect that it is what solved my problem. 73, Rich VE3KI K3 #1595 > Thanks to everyone who responded -- as far as directional antennas go the > VX-3R yahoo \ > group pointed out that the hand held has a fairly directional AM antenna that > can be \ > use to chase down noise. > > I have been able to narrow the source of the noise down to the USB to Serial \ > converters or the USB Hubs themselves. The noise is getting into the ground > through \ > the serial interface on the K3 and then out to the coax shields. I'll have > to move a \ > heavy desk to determine which of the two potential offenders is actually > generating \ > the noise. > > I was curious if anyone else had experienced this with a K3 and USB<->Serial \ > converters -- the pulsing of the noise turns out to be HRD polling the K3 for > VFO \ > position -- once every 300ms -- and when I turn off polling the noise > stabilizes but \ > is still present. I am doing research to see what I can do to eliminate it. > > While chasing this down with my HT, I found several other sources of noise > -- all \ > within my shack, so I have a noise eradication project to embark on now. > > 73, > Mitch Mitchell, AE5HO > [email protected] > ______________________________________________________________ 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
