Interference/illegal transmission in Pittsburgh?

[fire42man]

Hey guys, for the past few months I've been getting unwanted interference in my shack in the Oakland part of town. Sometimes the transmissions are a guy yelling, other times it's just a carrier trailed with a roger beep (sounds like a Baofeng's beep), either way the transmissions are too brief and infrequent for me to pinpoint the source. Whatever it is puts out enough power to overload my RTL dongles and a BC760XLT giving them images in the 450-470MHz range, but my PRO-163 has no issues. Scanning the FRS/GMRS frequencies hasn't given me any luck so far.
While the source is probably on my block, I figured I'd toss a line to see if anyone else in the city has noticed anything.

 

[KevinC]

Search the CB band.

 

[soberbyker]

Search the CB band.

I second that. Here in Philly there's a bunch of overpowered guys on CB channel 6, aka the super bowl. There's one guy in a mobile that can bleed from 6 all the way to 19 if he's nearby.

 

[PGHSCANNERWACKER1]

116 uptown Pittsburgh is what I use to hear I haven't really scan the cb band lately in less I go on a road trip

 

[PGHSCANNERWACKER1]

Hey guys, for the past few months I've been getting unwanted interference in my shack in the Oakland part of town. Sometimes the transmissions are a guy yelling, other times it's just a carrier trailed with a roger beep (sounds like a Baofeng's beep), either way the transmissions are too brief and infrequent for me to pinpoint the source. Whatever it is puts out enough power to overload my RTL dongles and a BC760XLT giving them images in the 450-470MHz range, but my PRO-163 has no issues. Scanning the FRS/GMRS frequencies hasn't given me any luck so far.
While the source is probably on my block, I figured I'd toss a line to see if anyone else in the city has noticed anything.

best thing is to take video of the sound so other people might have heard it before

 

[k3fs]

Use the Signal Stalker on the Pro-163 when this is happening. Signal Stalker should work well for this purpose. This is likely a UHF source. What frequencies on the 760 are you receiving this on? I had a 760XLT with the tone board until recently. I really liked that radio. I cannot remember the IF frequency. You are likely hearing an image if the source is close to you. I think you can add or subtract 21.8 ( or it could be 21.6,) from the frequency you are receiving on the 760XLT. One of those should get you to the real frequency, and you should hear the source a little clearer. I'm fairly sure one of those numbers is close enough to the correct IF, that you should be able to find it.

 

[fire42man]

Use the Signal Stalker on the Pro-163 when this is happening. Signal Stalker should work well for this purpose. This is likely a UHF source. What frequencies on the 760 are you receiving this on? I had a 760XLT with the tone board until recently. I really liked that radio. I cannot remember the IF frequency. You are likely hearing an image if the source is close to you. I think you can add or subtract 21.8 ( or it could be 21.6,) from the frequency you are receiving on the 760XLT. One of those should get you to the real frequency, and you should hear the source a little clearer. I'm fairly sure one of those numbers is close enough to the correct IF, that you should be able to find it.

The 760 gets images on 453.4 and 453.7. I also have a BC72XLT set in close call mode since that seems to find signals faster than the 163 can.

 

[tvengr]

I think you can add or subtract 21.8 ( or it could be 21.6,)

Uniden scanners used a 10.8 IF, so it would be 21.6.

 

[Whiskey3JMC]

Search the CB band.

CB intermod on UHF? I'd doubt that. How powerful & close would the source have to be to bleed over that high up?

 

[fire42man]

I think you can add or subtract 21.8 ( or it could be 21.6,)

Uniden scanners used a 10.8 IF, so it would be 21.6.

That yields possible frequencies of around 432MHz and 475MHz. I want to lean towards the latter frequency, since my RTL dongles pick up intermod when they're tuned between 470-473 (I used to live near a commercial repeater sitting on 471, my dongle would get overloaded if it was within 3MHz of the transmitter)

 

[fire42man]

Just heard (approx. 21:50) a radio key up twice with the Baofeng roger beep on Fire 2 (453.85). It was loud and clear but I don't know if the operator keyed directly on the output frequency or the repeater input. I've heard it key up on a few county public safety frequencies over the past few days with the same signal strength, on channels I would normally expect weaker signals. Did anyone else catch it that happened to be monitoring Fire 2?

I'm starting to suspect that the guy yelling (cheering mostly) is from a different source than the key-ups, as the former comes in weaker on my 760. Neither signals triggered the close call on the BC72XLT

 

[nd5y]

You might check some of the default frequencies that some CCRs come with.

CCR Default Frequencies - The RadioReference Wiki

wiki.radioreference.com