开云体育

Hunting Down RFI

Brian Donovan - K2AS All Messages By This Member #1080 开云体育 Just wondering if anyone has any tools/tips for hunting RFI.? Lately I have noticed S9 noise levels on some bands, though the noise appears to be very wide-banded.? It is quite evident in the spectrum display when it is present, and seems to cover hf to 6 meters, but worst around the 10Mhz band.? It will to last for hours and then maybe go away for hours, but when it is present, it will occasionally stop for a few seconds and then start back up.? I seems likely to be a power line arcing issue. On my AM car radio, it seems to be worse both east and west of my house for maybe a ? to ? of a mile.? Hard to know for sure, as I only have the sound to judge. I did try walking around with a HT at 137Mhz AM and a 2 meter 3 el yagi, but not much luck, or I didn't go far enough. ? -- Brian -------------------------------------------------------------------------------- k2as@...
Brian Donovan - K2AS All Messages By This Member #1081 开云体育 Forgot to mention, no noise on rig w/o antenna, so I don't think anything is coming on the AC line. On 1/3/2025 3:49 PM, Brian Donovan - K2AS via groups.io wrote: toggle quoted message Show quoted text Just wondering if anyone has any tools/tips for hunting RFI.? Lately I have noticed S9 noise levels on some bands, though the noise appears to be very wide-banded.? It is quite evident in the spectrum display when it is present, and seems to cover hf to 6 meters, but worst around the 10Mhz band.? It will to last for hours and then maybe go away for hours, but when it is present, it will occasionally stop for a few seconds and then start back up.? I seems likely to be a power line arcing issue. On my AM car radio, it seems to be worse both east and west of my house for maybe a ? to ? of a mile.? Hard to know for sure, as I only have the sound to judge. I did try walking around with a HT at 137Mhz AM and a 2 meter 3 el yagi, but not much luck, or I didn't go far enough. ? -- Brian -------------------------------------------------------------------------------- k2as@...
Robert Karz All Messages By This Member #1082 开云体育 Brian, I have a portable general coverage RX that might help you track the problem down. Bob, K2OID On 1/3/2025 3:52 PM, Brian Donovan - K2AS via groups.io wrote: toggle quoted message Show quoted text Forgot to mention, no noise on rig w/o antenna, so I don't think anything is coming on the AC line. On 1/3/2025 3:49 PM, Brian Donovan - K2AS via groups.io wrote: Just wondering if anyone has any tools/tips for hunting RFI.? Lately I have noticed S9 noise levels on some bands, though the noise appears to be very wide-banded.? It is quite evident in the spectrum display when it is present, and seems to cover hf to 6 meters, but worst around the 10Mhz band.? It will to last for hours and then maybe go away for hours, but when it is present, it will occasionally stop for a few seconds and then start back up.? I seems likely to be a power line arcing issue. On my AM car radio, it seems to be worse both east and west of my house for maybe a ? to ? of a mile.? Hard to know for sure, as I only have the sound to judge. I did try walking around with a HT at 137Mhz AM and a 2 meter 3 el yagi, but not much luck, or I didn't go far enough. ? -- Brian -------------------------------------------------------------------------------- k2as@...
Brian Donovan - K2AS All Messages By This Member #1083 开云体育 Thanks for the offer, I'll let you know. It is interesting to watch my spectrum display, sometimes the intensity of the display will lower, but signal still at S-9.? Then occasionally it will suddenly go quiet and s meter will start to drop, then immediately start up again.? The way I see the display fluctuate pointed me to a power pole issue. I put my FT-857 back in the car and drove down the road and saw a definite peak about a quarter mile west, monitoring 20 meters with a hamstick on the roof of the car.? I tried my HT at 136.7500 AM, walked down the road to that area, and using my Arrow 2 meter yagi, found a peak on a pole.? Strangely, it was not a pole with 14KV, but just a Ginna warning siren pole.? But it peaked pointing right at the control box mounted on the side.? They do have a small vertical higher up, so there may be a transmitter in there, but not peaking where the antenna is higher up. So not sure if the s meter peak I'm seeing is the noise or some other RF.? The audio is definitely noisy there, and the area where it peaked with the FT-857 whilst driving by.? HF might be better if I can get a loop or something directional. I watched W4DD's video presentation.? His RFI Mapper looks interesting.? If I can get that working with my 857 easily, I might try it.? I might also throw together a 3 element yagi for 137MHz. I can't find a specific number at RGE to report RFI, so I'll probably wait until Monday to get a real person. Brian On 1/4/2025 2:24 PM, Robert Karz via groups.io wrote: toggle quoted message Show quoted text Brian, I have a portable general coverage RX that might help you track the problem down. Bob, K2OID On 1/3/2025 3:52 PM, Brian Donovan - K2AS via groups.io wrote: Forgot to mention, no noise on rig w/o antenna, so I don't think anything is coming on the AC line. On 1/3/2025 3:49 PM, Brian Donovan - K2AS via groups.io wrote: Just wondering if anyone has any tools/tips for hunting RFI.? Lately I have noticed S9 noise levels on some bands, though the noise appears to be very wide-banded.? It is quite evident in the spectrum display when it is present, and seems to cover hf to 6 meters, but worst around the 10Mhz band.? It will to last for hours and then maybe go away for hours, but when it is present, it will occasionally stop for a few seconds and then start back up.? I seems likely to be a power line arcing issue. On my AM car radio, it seems to be worse both east and west of my house for maybe a ? to ? of a mile.? Hard to know for sure, as I only have the sound to judge. I did try walking around with a HT at 137Mhz AM and a 2 meter 3 el yagi, but not much luck, or I didn't go far enough. ? -- Brian -------------------------------------------------------------------------------- k2as@...

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