Sudden Loss of Reception
- Thread starter emsflyer84
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So, a bit of history, I used to pick this up fine from my house. When I realized I wasn't getting it anymore (sometimes broken) I went and shortened my coax run and bought new cable and connectors thinking I had an issue with my feed line. No improvement. I thought maybe I had an antenna issue. Put a new antenna up, no improvement. I opened the squelch all the way on my scanner on that frequency and saw like 3-5 bars of signal, telling me it's picking up interference. I haven't tried on other frequencies because everything else I scan is strong enough that it's still coming through fine. This particular frequency is on the edge of my reception range, but again I was picking it up fine previously. Unfortunately I don't know exactly when this started happening so I don't know what might have changed at my house. We've bought some random electronics, who knows what it could be.... Pretty much everything I scan is in that public safety VHF range.
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Did you do any of the suggestions in the other thread?
Yes, I was about to start with that, just checking to see if there are any other ideas as well. I can start throwing breakers room by room, I just have to figure out what to do when I get to the room where the scanner is, etc. I suppose I'll connect a handheld direct to the antenna line when I do that...
Run the scanner off a battery then turn power off to the whole house. That will instantly tell you if it’s within your house and under your control without wasting time with individual breakers. If you find your house is making noise then go room by room shutting off breakers to narrow things down.
RFI-EMI-GUY
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Many if not most VHF scanners get wiped out from high power paging and/or NOAA VHF weather transmitters. A third problem is FM broadcast interference. The reason is that the receivers are rather broad band and all this other stuff saturates the "front end" of the receiver, the RF preamp, the mixer, sometimes first IF. You can get notch filters from PAR specific to your intereference. You can also get band stop filters from Mini Circuits. With one high pass filter and one low pass filter, you can create a window or band pass to block broadcast or other out of band. However with VHF paging and NOAA , you pretty much need to notch them out.
PAR Electronics | Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave listening enthusiasts
PAR Electronics Inc. Filters for the commercial 2 way market, MATV, FM broadcast, laboratory, marine industry, amateur radio, scanner and short wave
www.parelectronics.com
MTS2000des
5B2_BEE00 Czar
Also a good idea to check the noise floor. VHF in particular, is full of hash and trash thanks to Chinaturd unintentional radiators. Back when the FCC cared, part 15 used to mean something. That being said, the idea of getting a baseline for what the noise floor is on that desired frequency with everything on, then turned off, should be a starting point.
Quick update. Shut all the breakers off in my house yesterday and ran a handheld scanner on batteries. No real improvement! Now I’m at a loss. Maybe there is outside interference that is being picked up by my roof antenna and not the small mobile antenna on my car? Can’t really figure it out. Next step will be to take the handheld up on the roof and plug directly into my roof antenna and rule out any antenna feed line issues.
