Looking For Help w/ Reception Issue

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Emsflyer84
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Looking For Help w/ Reception Issue

Post by Emsflyer84 »

Hey all, looking for someone smarter then myself to help out with a very strange issue I'm having. I'm in central NH and run a Broadcastify feed for Carroll County. I've always been able to pick up Conway PD dispatch from my house (conventional digital) using the following equipment: Uniden BCD325p2 scanner and Diamond X50C2 antenna on the roof. I had regular low grade coax running down the side of the house into the basement and tapped into my home cable network of wires throughout the house so I could plug my scanner into a cable jack in the wall by my desk. NOT ideal but it worked for everything I needed it for. Recently (past couple months?) I've noticed I'm no longer getting Conway PD, except once in a while it comes in broken, choppy and unreadable. I figured I must have cable issues, moisture, connection problems, etc. Invested in new LMR-400 and shortened the cable run so now it goes right from the antenna, down the side of the house and into my office window right to the back of the scanner. No real improvement in reception. I even tried a different antenna with similar results. I can't really improve anything more on my end. Side note, sometime in September I changed out the scanner for a BCD996P2.

Here is the crazy part. I can pick up Conway PD in my car with a mobile antenna only a short distance from my house, even at lower elevation. But EVERYTHING else comes in better on my home setup with roof antenna then in my car.

A few theories:

- Interference from something in my house that is specifically effecting that one frequency
- Something changed on the transmit end and my house is no longer line-of-site, or less so then before
- Something changed with the way they simulcast and the way my home antenna is picking up multiple transmissions where my mobile is only picking up one site

Any other theories or ideas would be appreciated. Thanks!
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W1KNE
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Re: Looking For Help w/ Reception Issue

Post by W1KNE »

Emsflyer84 wrote: 05 Jan 2024 13:24 A- Interference from something in my house that is specifically effecting that one frequency
B- Something changed on the transmit end and my house is no longer line-of-site, or less so then before
C- Something changed with the way they simulcast and the way my home antenna is picking up multiple transmissions where my mobile is only picking up one site
I see that Conway PD is on 155.6400 with an NAC of 817h. Are you running the frequency the NAC programmed in?

OK try this. I labeled the suggestions above and will respond.

A is a likely candidate. Tune to the frequency using quick tune. (Press "Hold/Release", enter the frequency, press "Hold/Release" a second time.). Once you have it tuned in, open the squelch.
Turn it to zero. Do you show any bars on your signal meter? If you happen to see bars, especially 3-5 bars, you have interference. The "signal meter" on these scanners is dumb and only shows signal strength based on sheer raw signal.

B this is possible. In the car you hear them , in your driveway, or only when your further way. I suspect this would also prove A as a theory. Drive from the interfering source, and it gets better. So it's not easy to rule out B.

C this would be indicated by broken up garbage audio or occasionally getting a signal decode. Your reception in the car, unless you had a SDS100 and not the 325, would only be significantly better based on that.

I suspect A is your case here.
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Scott
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Re: Looking For Help w/ Reception Issue

Post by Scott »

I'd vote for A. There are so many things that can cause interference. Older style plasma HDTVs, solar panels, Chinese electronics, to include wall wort AC adapters, wifi, ethernet that does not use shielded cable, USB 3.0 connections with crappy cables, PC's, monitors. Have you added anything in the house recently. Have your neighbors? Tracking down interference is a female dog. I have fought it for years and have myself in a pretty good spot now. Some of the changes are amazing. I switched from an HDMI port on a monitor to the Dell port. Completely wiped out one interference source as a result. Sometimes simply identifying different circuits your plugs are on and moving a plug to another can make a difference. It takes time but when you find the source and eliminate it you'll be a happy camper.
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Re: Looking For Help w/ Reception Issue

Post by Scott »

I see we are redirecting b*tch to female dog, which is hilarious, and a source of interference in and of itself... xD
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Re: Looking For Help w/ Reception Issue

Post by W1KNE »

Scott wrote: 05 Jan 2024 20:29 I see we are redirecting b*tch to female dog, which is hilarious, and a source of interference in and of itself... xD
Only if you have the word censor turned on in your board settings. ;)
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Emsflyer84
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

Haha hey thanks for the input on this issue. I’m now leaning toward interference at my house. I’m no stranger to that, I spent months trying to track down bad interference a couple years ago, finally discovered it was power line noise from work they were doing on utility poles. I was driving up and down the road with an AM radio chasing static, shut all the power off to my house and hooked my handheld scanner right up to my antenna, etc. That’s how I knew the source wasn’t my own house because the interference stayed when I did that. Anyway, this morning I was in my car in my driveway and picked up Conway PD, sitting about 30 feet lower than my roof antenna! Then the same broadcast came over my broadcastify feed from my home scanner setup and it was unreadable. So I think the issue is in my house. My son has a gaming PC with all kinds of different keyboards, monitors, etc, but he’s on a different floor and other side of the house from my scanner. I did buy a wired keyboard and mouse with RGB lighting and stuff for my computer, those wires run down right next to the scanner. Maybe I’ll mess around with that. I’m thinking it’s probably my computer that’s the issue just because when I was sitting in my car today I was actually closer to my sons room then my scanner and computer is. Could be anything I guess. I’ll start by cutting all the power and see if it goes away to confirm it’s my house.

Question… will the interference affect the scanner itself? Or is the interference picked up by the antenna? The antenna and coax is basically all outside, so not sure…. Thanks!
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Re: Looking For Help w/ Reception Issue

Post by kelton.dray »

I put a PTZ camera on the top of my tower and the interference that thing caused wiped out the RX on both VHF and UHF repeaters, plus who knows what else.
I'll take it down and spectrum analyze it when the weather is more agreeable. Chinese do not care about RFI whatsoever.
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Re: Looking For Help w/ Reception Issue

Post by Scott »

W1KNE wrote: 06 Jan 2024 06:04 Only if you have the word censor turned on in your board settings. ;)
You know, I completely missed that and thought it was under the hood at the message board level, i.e. a "for all users" setting. Maybe it was at one point and that changed in the newest version. Anyway, cool. I fixed that.

Anyway, interference...yep the Chinese lead the way with that, both "professionally" and with the crappy products they produce, namely their 12VDC adapters. Another good option is to buy a set of the snap-on ferrite chokes. Your mileage may vary widely with them but sometimes they do their jobs if they are used properly. Other amazing things like the re-routing of USB cables and substituting a different length USB or even AC power cable can make a world of difference. I had a situation with AC power where adding a short heavy duty appliance extension cord eliminated interference. It's crazy stuff and sometimes the weirdest solutions work.
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Emsflyer84
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

W1KNE wrote: 05 Jan 2024 17:50 I see that Conway PD is on 155.6400 with an NAC of 817h. Are you running the frequency the NAC programmed in?

OK try this. I labeled the suggestions above and will respond.

A is a likely candidate. Tune to the frequency using quick tune. (Press "Hold/Release", enter the frequency, press "Hold/Release" a second time.). Once you have it tuned in, open the squelch.
Turn it to zero. Do you show any bars on your signal meter? If you happen to see bars, especially 3-5 bars, you have interference. The "signal meter" on these scanners is dumb and only shows signal strength based on sheer raw signal.

B this is possible. In the car you hear them , in your driveway, or only when your further way. I suspect this would also prove A as a theory. Drive from the interfering source, and it gets better. So it's not easy to rule out B.

C this would be indicated by broken up garbage audio or occasionally getting a signal decode. Your reception in the car, unless you had a SDS100 and not the 325, would only be significantly better based on that.

I suspect A is your case here.
Thanks for the great tips here. I tuned to that specific frequency and turned the squelch all the way open “0” and got the typical squelch static and 5 bars on the signal meter. Is this what you were referring to? If I didn’t have any bars on the meter, I’d still hear the squelch static, right? Thanks again.
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Re: Looking For Help w/ Reception Issue

Post by W1KNE »

Emsflyer84 wrote: 06 Jan 2024 21:10 Thanks for the great tips here. I tuned to that specific frequency and turned the squelch all the way open “0” and got the typical squelch static and 5 bars on the signal meter. Is this what you were referring to? If I didn’t have any bars on the meter, I’d still hear the squelch static, right? Thanks again.
Yes!! Exactly. If you hear static but see 5 bars on your signal meter with the squelch set to 0, you are getting interference. You won't hear it, but you'll "see" it.
Good catch.
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Emsflyer84
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

W1KNE wrote: 06 Jan 2024 22:15 Yes!! Exactly. If you hear static but see 5 bars on your signal meter with the squelch set to 0, you are getting interference. You won't hear it, but you'll "see" it.
Good catch.
Great, now the fun part begins. I’ll start throwing breakers….
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

W1KNE wrote: 06 Jan 2024 22:15 Yes!! Exactly. If you hear static but see 5 bars on your signal meter with the squelch set to 0, you are getting interference. You won't hear it, but you'll "see" it.
Good catch.
Hey there again, refreshing this thread. I ended up testing for interference by killing every breaker in my house. No real improvement in reception! So now I'm pretty confident my antenna is picking up something outside. Again, the cray thing is I can sit in my car in my driveway and get better reception then my roof antenna is getting 50 feet away. Maybe with the height of the roof antenna it's picking up interference that my mobile unit is not? Man this is crazy. I'll keep experimenting.
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Re: Looking For Help w/ Reception Issue

Post by ecps92 »

How does the radio work without the external / outside antenna ??

Wondering if it could be the Antenna, Connectors, Coax now being your issues
Water, bad connections, broken coax or the antenna??
Emsflyer84 wrote: 31 Jan 2024 08:40 Hey there again, refreshing this thread. I ended up testing for interference by killing every breaker in my house. No real improvement in reception! So now I'm pretty confident my antenna is picking up something outside. Again, the cray thing is I can sit in my car in my driveway and get better reception then my roof antenna is getting 50 feet away. Maybe with the height of the roof antenna it's picking up interference that my mobile unit is not? Man this is crazy. I'll keep experimenting.
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Emsflyer84
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

ecps92 wrote: 31 Jan 2024 08:50 How does the radio work without the external / outside antenna ??

Wondering if it could be the Antenna, Connectors, Coax now being your issues
Water, bad connections, broken coax or the antenna??
So when this issue started I thought the same thing. So I bought all new LMR-400, shorted the run by about half, and have since tried another antenna on the roof. Same issues. The only thing I haven't tried yet is taking my handheld scanner to the roof and plugging in directly to the antenna to rule out any line / connection issues. That's next. I also have an FM notch filter I want to throw in-line to see if it can catch any FM interference I might be getting, but that's a shot in the dark.
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Re: Looking For Help w/ Reception Issue

Post by CG »

When I had first put up my antenna to a new, higher location, I was thinking I was hearing music in the interference. Sure enough, the Par filter for FM fixed it. I also ended up getting a NOAA WX filter which helped as well
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

CG wrote: 31 Jan 2024 09:08 When I had first put up my antenna to a new, higher location, I was thinking I was hearing music in the interference. Sure enough, the Par filter for FM fixed it. I also ended up getting a NOAA WX filter which helped as well
Thanks, I'll try the filter and see what happens.
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Re: Looking For Help w/ Reception Issue

Post by n1zyy »

Emsflyer84 wrote: 06 Jan 2024 07:33 Question… will the interference affect the scanner itself? Or is the interference picked up by the antenna? The antenna and coax is basically all outside, so not sure…. Thanks!
When you were looking at the 5-bar signal meter with the squelch open and no signal, did you try disconnecting the antenna? That's how I'd try to detect whether it's coming down from the antenna, or being picked up locally by the scanner.

Is the scanner dedicated full-time to Conway PD? I'm curious if it's still receiving other signals well.

Also, apologies if you already tried these things and I just missed it and am making a donkey of myself. ;)

I was tempted to get one of those Par filters myself for travel, but it looks like they're tuned for the ham band and have something like 5-10 dB loss in the broader 150ish MHz range. Although it sounds like maybe that's a totally acceptable cost in this case, if things sound fine in your car.
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Re: Looking For Help w/ Reception Issue

Post by CG »

The two PAR filters I use are PAR VHF-FM and PAR VHF-SYM(162)HT. There is no large loss in the VHF PS band
VHF-FM insertion loss is -1.43 at 120MHz (you lose the bottom of the air band)
VHF-SYM(162) insertion loss is -2.89 at 160 and -3.11 at 164.8 (a bit at the top of the VHF PS band, a bit at the bottom of the Fed band)
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

n1zyy wrote: 31 Jan 2024 19:46 When you were looking at the 5-bar signal meter with the squelch open and no signal, did you try disconnecting the antenna? That's how I'd try to detect whether it's coming down from the antenna, or being picked up locally by the scanner.

Is the scanner dedicated full-time to Conway PD? I'm curious if it's still receiving other signals well.

Also, apologies if you already tried these things and I just missed it and am making a donkey of myself. ;)

I was tempted to get one of those Par filters myself for travel, but it looks like they're tuned for the ham band and have something like 5-10 dB loss in the broader 150ish MHz range. Although it sounds like maybe that's a totally acceptable cost in this case, if things sound fine in your car.
Thanks for the reply, I did not try to disconnect the antenna with the squelch open, that's a good idea, I'll try it.

The scanner is covering all of my county, Conway is the farthest away. There is another town that's not too far that I sometimes can't get well either, but can get in my car, so I don't think the issue is specific to that frequency, but more about the distance.
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

Ok guys, quick update. I manually listened to a frequency this morning, opened the squelch all the way and got the same 3-4 signal bars on the screen. When I disconnected the antenna they went away and the static got “cleaner” sounding. Tried on several frequencies with the same result. Then I plugged the antenna back in, signal bars back immediately. Then I noticed what sounded like a digital phone ringing off and on in the static. Only heard this with antenna connected. I assume this is what is causing my troubles. I got a video of that noise. I also a suspect it’s affecting reception across the board, but the stronger signals are just overpowering the interference so I’m only noticing it on more distant frequencies. Anyway, I’m not sure how to link a video here but I’d be happy to send it to anyone who wants to take a stab at what the noise might be. Thanks, we’re getting closer to figuring this out!
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

Here is a link to the video:

https://youtube.com/shorts/uqYgGwCdy2g?feature=share

I also did the same test with my handheld in my car in the driveway, tuned to the same frequency and opened the squelch. No noise or signal bars. My roof antenna must be picking up something my mobile isn't.
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Re: Looking For Help w/ Reception Issue

Post by CG »

not very clear but paging interference perhaps?
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

Yes it's hard to hear but does sound like that. Not sure what would have come up in the past 6 months or so that wasn't there before.... I'll have to do some more research.
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Re: Looking For Help w/ Reception Issue

Post by n1zyy »

+1, I think that's POCSAG: https://www.sigidwiki.com/wiki/POCSAG (turn your sound down before playing those clips, they're loud and obnoxious). That "doo-DOO!" sound is pretty distinctive, and the other annoying data sounds are likely indistinguishable from static.

See if you're hearing a very strong signal from them on 152.6000 or 157.7400. Those are the ones that periodically cause me headaches. In several spots they're licensed for 1000+ Watts ERP so they can be a real nuisance. (I'm sure you'll hear a paging transmitter on at least one of those frequencies, but the question is whether they've got a ludicrously strong signal audible if you tune away a bit. Obviously neither of those signals should be heard on 154.64, and yet it sounds like one of them is.) If this is what it is, the aforementioned Par filter is probably precisely the fix you need.

I bet that what's happening is that in your car, the paging signal is not so incredibly strong that it's causing intermod, but the higher-elevation, higher-gain antenna on your house is bringing the paging signal up to the point that it's more than the radio can cope with.

Edited to add: I once tried to get some 2-meter QSOs for Field Day atop Mt. Uncanoonuc. One of those frequencies has a paging transmitter up there, and I ultimately disconnected my radio's antenna and it was still coming through as S9+60 on the S-meter on 146 MHz. That was... not a successful trip. xD
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Emsflyer84
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Re: Looking For Help w/ Reception Issue

Post by Emsflyer84 »

n1zyy wrote: 03 Feb 2024 13:41 +1, I think that's POCSAG: https://www.sigidwiki.com/wiki/POCSAG (turn your sound down before playing those clips, they're loud and obnoxious). That "doo-DOO!" sound is pretty distinctive, and the other annoying data sounds are likely indistinguishable from static.

See if you're hearing a very strong signal from them on 152.6000 or 157.7400. Those are the ones that periodically cause me headaches. In several spots they're licensed for 1000+ Watts ERP so they can be a real nuisance. (I'm sure you'll hear a paging transmitter on at least one of those frequencies, but the question is whether they've got a ludicrously strong signal audible if you tune away a bit. Obviously neither of those signals should be heard on 154.64, and yet it sounds like one of them is.) If this is what it is, the aforementioned Par filter is probably precisely the fix you need.

I bet that what's happening is that in your car, the paging signal is not so incredibly strong that it's causing intermod, but the higher-elevation, higher-gain antenna on your house is bringing the paging signal up to the point that it's more than the radio can cope with.

Edited to add: I once tried to get some 2-meter QSOs for Field Day atop Mt. Uncanoonuc. One of those frequencies has a paging transmitter up there, and I ultimately disconnected my radio's antenna and it was still coming through as S9+60 on the S-meter on 146 MHz. That was... not a successful trip. xD
I think you nailed it! Here are the two frequencies you mentioned.

https://youtube.com/shorts/2QAgINBewW8?feature=shared

https://youtube.com/shorts/_PlAxq1mduc?feature=shared

https://youtube.com/shorts/5REOI96bm80?feature=shared

Guess I need to figure out a solution now. Very interesting, these signals seem very strong. There must be something in my town that’s putting this out. Maybe paging at the hospital? Small town with not many business big enough for paging systems. Hospital and Schools are about it…
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