James, The classical method is to use audio isolation transformers between the rig audio in/out and the soundcard, and opto-isolators on the serial port line(s) used for the PTT switching (assuming y
Dear John, Jim LF Group, Oddly though Jame's twin spots of Jim are 100Hz apart: M0BMU 0.503944 M0BMU 0.503844 My signal is on a nominal 503840 centre frequency... I think what has happened is that, i
Dear Jim, LF Group, Me too. I am getting 3 traces (!) from Jim M (he is 9+10 and audible!) and a biggish one from Gus too I am seeing low-level (about -25dB) sidebands on your signal at +/-50Hz and +
I think you find that is caused by 50 hz mains hum .... may be a hum loop in the audio system / pc-tx earthling , not likely to be psu problem as frequency is 50 (fund) and 150 ( 3 rd harm) I had a s
JIm, I think you find that is caused by 50 hz mains hum .... may be a hum loop in the audio system / pc-tx earthling , not likely to be psu problem as frequency is 50 (fund) and 150 ( 3 rd harm) I ha
Ferrite, Ferrite and more Ferrite then! Any suggestions as to where best to place clip on cores? Mains lead? Power lead from PSU (Icom PS55) to rig (IC735)? All leads from ZLP interface to laptop? (D
