Strange signal on 156.165

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arlojanis
Posts: 1055
Joined: Mon Jan 28, 2002 4:00 pm

Strange signal on 156.165

Post by arlojanis »

I am getting an interference signal on 156.165. The frequency very slowly
drifts from 156.135 up to 156.170 and back down. The strength varies from weak to strong. The modulation is just a steady buzz with no changes. It sounds like a power supply that is not completely filtered. Do you hear anything thing like this on VHF? I remember the Winegard TV amp that did this on UHF.
"The world runs on radio."
Will
Posts: 6823
Joined: Tue Sep 04, 2001 4:00 pm

Re: Strange signal on 156.165

Post by Will »

Arlo,

Time to get out your VHF yagi and do a little direction finding.
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Renamon
Posts: 380
Joined: Tue Apr 09, 2002 4:00 pm

Re: Strange signal on 156.165

Post by Renamon »

That's one of the freqs for the snow plows in my town! LOL

Ok sorry, back to the post.
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tuckerm
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Joined: Thu Jun 10, 2010 12:21 pm

Re: Strange signal on 156.165

Post by tuckerm »

Does it happen everywhere or just your house? Is it only in your car? We need some more information
Schrodinger's Radio: It is simultaneously too loud and too quiet, but you will never know which until someone transmits.
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arlojanis
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Joined: Mon Jan 28, 2002 4:00 pm

Re: Strange signal on 156.165

Post by arlojanis »

Update: Spur signal is coming from a group of towers about 35 miles away. There is a 1000 watt weather transmitter, wireless internet transmitters, a lot of microwave antennas, and many two-way antennas. A visit to the hill proved this is where signal is coming from. Since the drifting spur is always there, I am thinking weather transmitter may be causing it. Signal strength is strong on my tower and can be tracked from mobile for 20 miles.
"The world runs on radio."
Will
Posts: 6823
Joined: Tue Sep 04, 2001 4:00 pm

Re: Strange signal on 156.165

Post by Will »

Good job tracking the spur.

Now it is time to notify the site manager. If no results, then notify the FCC Field office.
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Bill_G
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Joined: Thu Sep 17, 2009 5:00 am

Re: Strange signal on 156.165

Post by Bill_G »

Do both at once - notify site owner AND contact the FCC. Ask for their help in locating the spurious emissions. Their gear is better than yours, and their presence tends to promote speedy cooperation. Set a date and time for a site meet. Might be a bad power supply. Might be a bad PA. Might be somebody running barefoot.
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arlojanis
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Joined: Mon Jan 28, 2002 4:00 pm

Re: Strange signal on 156.165

Post by arlojanis »

Problem was a new VHF TPL brand amp self oscillating during standby.
"The world runs on radio."
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