January 19, 2017
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I am seeing some weird noise on mainly the low bands here with the new vertical antenna. It is fairly broadband and the rig’s noise blanker seems to effectively null it but I would like to track down the source.The weird part is that is seems to go away on it’s own during daylight hours and return in the evening. I haven’t been able to track a specific time yet. I suspect somethjing here in the shack is causing the problem. I walked around the property yesterday with a battery powered receiver and I see the noise coming from the wall around my workstation. I suspect a bad patch cable as this has caused problems before and I did add some patch cables that may be a bit dodgy.
November 30, 2015
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Started noticing RFI issues again after I swapped out the LDG tuner for the new MFJ. Problems were noted mainly on 40m and below this time. I also noticed the tuner would not find a good match on 15m and 17m. I checked all the connections today as well as the cable routing today. I found a subtle problem with one of the patch cables I was using in which the connector was rotating a bit. I replaced it and the RFI went away on all bands but 80m. The tuner now seems to be finding a match on 15m and 17m without any issues. Looks like everything is running well again now.
September 7, 2015
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Now that the RTL-SDR songle is working again as my panadapter…I noticed a lot of noise spikes on my HF spectrum. Tracked it down to the 12V 15A supply I was using for the FT-2900R. I tried to suppress the noise using ferrites but it didn’t have an effect so I am figuring the supply itself is radiating. I moved the FT-2900R to the Samlex supply and it is now sharing with the Yaesu FT-450D. Not a problem running both as long as I don’t try to transmit with both at the same time. I’ll keep the noisy supply when I try and operate the FT-2900R on the 2m Moxon when I get the mast up and running.
Otherwise, the rig is running real smooth now and playing very nicely with all my computer and USB peripherals.
September 6, 2015
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I had not mentioned this before but ever since I set up my HF station last year I have had off and on problems with RFI in various devices. This was not much of a problem when 10m was open as I spent much of my time there and my problems were showing up mainly on 20m. First there was the issue of my Eaton ACFI breakers tripping when transmitting on anything below 17m. This is a well documented problem but I lived with it until just last week when I replaced them with standard breakers and installed GCFI outlets. That settled the issue of visiting the breaker box after playing radio.
It seemed as though whenever I made even minor changes to the station wiring I would get RFI into either USB peripherals or get RF breaking the squelch on my 2m rig which I leave on when using HF. The worst problems of this type were on 20m. SSB would be relatively minor at 100W but PSK31 on 30W would drive some stuff crazy. Her’s a list of stuff that would go wacky at various times:
- USB Conference speaker would light up like a Christmas tree and hang
- RTL-SDR dongle would over load when I transmit and freeze
- USB keyboard would lose connection
- SignaLink would drop occasionally during transmit
- Squelch would break on my 2m rig when using PSK31.
- LCD computer monitor would pick up RFI during transmit
- Cable modem would drop internet signal.
These were the main issues and I should note that these did not always happen. The last straw came when the keyboard would lock during PSK31. Makes it hard to close a QSO when you can’t type….arrrgh!
So the battle was joined. First up I adjusted all the wiring on the radio and tuner and attempted to keep things from being to close to cables carrying RF. I added a line isolator right out of the rig. Some improvement preventing the 2m rig RFI but not much else. Off to Amazon and Ebay next to buy some snap-on ferrites. Didn’t have much luck with these initially. Today I got into it a lot deeper and found success. A snap-on ferrite on the power supply wire to the cable modem and making sure the feed-line was not in proximity to the cable line outside fixed the Internet issue. Next the USB cables. Ideally, six turns around the snap-on ferrite applied to the USB cable where it connects to the computer settled down the USB speaker. The same was done with the SignaLink, RTL-SDR dongle and mouse, keyboard USB lines. Also coiled up the excess wire into an air-choke. The results have been very nice. Everything is behaving now. The RTL-SDR dongle was moved a few inches away from the radio and with the snap-on ferrite it no longer overloads when I transmit.
December 2, 2014
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About the time I set up my station, I updated and repaired some electrical issues around the house. Part of this was for the radio setup. I added some ground rods and bonded them to the main house ground rod. I have one rod outside my station and the other is over by the where the antenna is installed.
Inside the house, I had to replace a GFCI breaker that was faulty on my load center. This breaker controlled by outside outlets as well as the bathroom outlets. While I was at it I had the electrician add a second one to cover some outlets near the kitchen sink. All was well for a while.
I started noticing that the GFCI would trip on both new breakers. I suspected the radio but didn’t see a correlation until I started using PSK31 on 20m. I started digging around some more and found that what was installed were Eaton AFCI breakers. These are well know to be susceptible to be tripped by HF signals in the 20m to 12m range. So using 10m everything was ok. When I tried 20m PSK31 transmission the breakers tripped almost immediately. Go figure….
So my plan now is to have the electrician come back in and replace the AFCI breakers with standard ones. Then I have to replace about five standard outlets with Leviton GFCI types. That should so the trick.