Tonight I hooked up my little TH-F6A to the same antenna and got the same noise. I do have to test out my radio, but I am 85% convinced that it is QRM from a pole transformer located about 25 ft from the long end of my OFDP. This is a reasonably new transformer, since they replaced it about 5 years ago when the old one blew. Anyone have experience with getting the electric company to do a RFI survey?
On the down side, I carried my AM radio to my back yard and heard no detectable interference. This is turning into a real mystery. Mark N5PRD > On Feb 3, 2021, at 6:55 PM, Gus Bernard via BVARC <bvarc@bvarc.org> wrote: > > What Rick says. Then try taking it portable, away from the QTH and power > lines. > > Gus, K5GMB > > On Sun, Jan 31, 2021 at 7:33 PM Mark Brantana via BVARC <bvarc@bvarc.org > <mailto:bvarc@bvarc.org>> wrote: > I am reaching out for ideas on a radio issue. I have installed an IC-745 Icom > with an MFJ-2010 offset fed dipole. The power supply is a 20A MegaWatt > switching power supply, which is located right next to the radio. The antenna > is under some high power-lines with the long leg 90 degrees to the > power-lines. I used my nanoVNA to study the band SWR response, and everything > looks reasonable, though some small adjustments may need to be made. Nothing > is grounded as yet. > > Here’s my problem. I am only attempting to receive at this time and I get > consistent QRM white noise across all bands to the point where I can barely > pick out some voices, etc. > > I am confident that the antenna is properly connected due to my antenna study. > I don’t believe the power lines are an issue, since the problem would likely > be more isolated show up as birdies at certain frequencies. > The radio settings seem to all be correct according to the manual. > Lack of grounding, but again the white noise is generally consistant across > the spectrum. Still, this could be the problem. > I have turned off my computer, so there no QRM from its power supply. > It does not help to have the switching power supply right next to the radio, > but other users give good reports on this model and no QRM issues are > mentioned. > I tried the radio at different times of the day on 20-m voice band, with the > same noisy result. > It could be the net result of a large number of small device transformers, > but I doubt it. > I turned off the wifi, and still no change. > > Hmm… I am a little stumped. Any thoughts or ideas? Personal experiences? > > Mark > N5PRD > ________________________________________________ > Brazos Valley Amateur Radio Club > > BVARC mailing list > BVARC@bvarc.org <mailto:BVARC@bvarc.org> > http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org > <http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org> > ________________________________________________ > Brazos Valley Amateur Radio Club > > BVARC mailing list > BVARC@bvarc.org > http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org
________________________________________________ Brazos Valley Amateur Radio Club BVARC mailing list BVARC@bvarc.org http://mail.bvarc.org/mailman/listinfo/bvarc_bvarc.org Publicly available archives are available here: https://www.mail-archive.com/bvarc@bvarc.org/
