Totally random interference?

[RedPenguin]

I have for years never had any issue receiving Metro Police 453.650 (various times I picked them up without any antenna attached), South Police 453.375, Fire 453.225, UPJ PD 453.15.

Yet for a few months now, I have gotten an interference problem like I have never seen.

I get interference that appears to be there one minute and gone the next.

I will for days be able to hear 453.650 for example, then it will start getting a tad staticy then a pure blackout of that frequency then usually the next day when the reception returns.

Sometimes it's just a few hours with no signal.

I have tried turning off/unplugging virtually every device in the room like computers, TVs, VCRs, anything.

I also tried in AM mode on the frequency running past various electronics in the room, nothing seems to hit.

I also tried turning off any CFL light bulbs, everything.

 

[RedPenguin]

Results

I tried listening to my scanners without any CFL bulbs on at all and I figured out they may possibly have created a tiny bit of static but it doesn't seem to be the amount I am experiencing.

I have noticed certain frequencies which are further away seem to be acting up.

Like 453.300 and 453.475 which are both about 15-20 miles away, not too bad, seem to really be having this issue.

453.475 will be perfectly normal for the longest time except a tad amount of static and random dropouts but it's totally listenable. Then all the sudden, I will totally not receive the channel.

Yesterday, 7AM-9AM I totally could not pick it up, then it worked fine then it stopped working until 2PM today.

But the strange part is a scanner in the very next room an old Regancy 45-chan doesn't seem to have this issue for the most part, but I can't easily move the scanner as the PC that controls/records it is in this room.

 

[ScannerSK]

I usually grab a scanner with the AM mode option and then walk around the house and locate the interference.

 

[RedPenguin]

Yea

I usually grab a scanner with the AM mode option and then walk around the house and locate the interference.

Yea I tried that, I may have to try it again.

Whatever is doing it must not be doing it when I check because I never seem to get major hits.

 

[fineshot1]

inband strong signal overload

It sounds like inband strong signal overload to me but difficult to tell over the internet.

Have you started searching uhf while it is happening to see if you can find a strong
and new station near you?

 

[RedPenguin]

It sounds like inband strong signal overload to me but difficult to tell over the internet.

Have you started searching uhf while it is happening to see if you can find a strong
and new station near you?

No, but I will definitely give that a try when it happens again. So far everything is working perfectly, so I will have to wait until something happens I assume.

 

[N8IAA]

No, but I will definitely give that a try when it happens again. So far everything is working perfectly, so I will have to wait until something happens I assume.

What scanner are you using that is receiving the interference? The 330T? The BC15? I could understand with the wide receive of the 330 that noise generated will get into the scanner. I run multiple scanners near all sorts of wifi enabled devices and occasionally on milair frequencies there is some intermittent noise.
Larry

 

[W6KRU]

Yet for a few months now, I have gotten an interference problem like I have never seen.

I get interference that appears to be there one minute and gone the next.

Haven't seen it since 2009?
http://forums.radioreference.com/general-scanning-forum/158543-can-rfi-emi-temporary.html

 

[RedPenguin]

Well

Haven't seen it since 2009?
http://forums.radioreference.com/general-scanning-forum/158543-can-rfi-emi-temporary.html

Well I have already apologized for all that stuff and that was strictly 453.350MHZ which has nothing to do with the problem this time.

Also after months of messing with it, apparently the decision to put a data channel one NFM channel away from a voice channel, is just going to mess with any scanner that attempts to listen to the voice channel. This was found to be the answer because no scanner besides my BCT15 can listen properly. My BR330T can't, my friends BC346XT, and a few other people with local scanners in totally different sections of my area can't listen to the channel without the interference. Even the company themselves is having interference with the data and their voice.

 

[RedPenguin]

Multiple

What scanner are you using that is receiving the interference? The 330T? The BC15? I could understand with the wide receive of the 330 that noise generated will get into the scanner. I run multiple scanners near all sorts of wifi enabled devices and occasionally on milair frequencies there is some intermittent noise.
Larry

Well the 330T is getting the problem on 453.475 while my BC147XLT and my Pro-2028 is getting it on 453.375, and my Pro-2028 sometimes gets it on 453.650.

For some reason the BCT15 seems to be alright.

650 is the one that's really amazing because that was always the best received channel besides NOAA weather.

 

[RedPenguin]

I got some where

Well so far I have gotten somewhere.

I have swapped the Pro-2028 and the BC147XLT.

I have a suspicion that the 147 is not really picking up that great even though I have put a Diamond RH77CA on it.

So I decided to put the best signal channel on it 453.650 which sounds very decent and threw all the channels that were one it to the Pro-2028.

So far it's sounded a fair amount better.

So far it seems to mainly be 453.375 (South PD) and 453.475 that just get totally staticy.

Also in search mode I am not hitting on any nearby UHF stations.

EDIT: One thing I found odd so far is, I am picking up my local NOAA (162.4) at 465.5MHZ.

Also something must be going wacky with my BC147XLT, I seemed to be getting 464.275 on my Ch 1 which was set to 453.650, like it was bleeding though, but I had one of the other channels set to that. I tried 0'ing out the other channels but it just said Error, so I just set all 16 channels to 453.650 and for some reason the 147 sounds excellent now.

 

[RedPenguin]

Possible Problem

It looks like I may have actually found the problem.

It appears that Centre Communications's radio systems near or at the Fire Tower on Laurel Mountain are quite possibly the UHF transmitters that are messing with my radios.

I noticed that Med Star on 464.275 no where near Metro PDs 453.650 was no where near to normally cause interference but at total random MedStar is heard on 453.650 on my BC147XLT.

Also I think the totally random clicks that I am experiencing on some other channels like 453.475 might actually be from what appears to be a private LTR system at the same location.

According to a map the towers can't be much further than 1-5 miles from me.

 

[RedPenguin]

453.475 Explained

It appears I most likely found the 453.475 problem exactly.

It looks like The State of PA was nice enough to put an OpenSky Tower CAM02 right on Laurel Mountain within 2 miles from my house and not only that put 453.4625 as one of the frequencies only 12.5KHZ or an NFM channel away from 453.475.

I thought the OpenSky system was going to use more like 800-900MHZ or at least not the 453 range.

 

[RedPenguin]

453.475 may be solved.

I may not know the exact cause of what sounds like an LTR Passport system on 453.475 when you turn off CTCSS. (Sounds like keying up 2-4 seconds), as after searching the FCC database and using the scanner to search, it seems there is really no LTR system or similar around that frequency range.

I seem to get this on any of my four scanners even outside my house.

But it appears that my BR330T may have totally hated being hooked up to the PC Programming Cable for bcTool logging.

After unhooking it to move the scanner, it seemed like it maybe was picking up again and so far it has not stopped picking up the channel.

I was using the cable for bcTool to sometimes record CTCSS/DCS tones but it looks like I cannot really do that anymore unless maybe changing which computer it's hooked to would help, but for now, I'm leaving it off.

EDIT: It's still going strong, but I will have to wait and see what happens tomorrow. I will be totally surprised if that is all it ends up being, because I thought like a poster said above, I was going to find out that it was UHF overload. Apparently so far in my case it was serial overload.