Re: Eliminating Buzzing

[suttles1972]

Re: Eliminating Buzzing

Hi all. Need some help on trying to rectify a problem I'm having with my BC296D. Here's what I have. I'm using a Scantenna Dipole antenna with 125 feet of RG6 shielded coax. The coax has a ground at the base of the antenna and another ground at the end of the 100' coax wire. The remaining 25' goes indoors, where the wire goes through a noise and interference canceller and off to the bnc connector of the radio. By doing this, I've eliminated all pager intermod and increased my listening distance. However, during the early morning hours, I pick up what sounds like an idling motor of a 2 cycle engine. I manage to get rid of it, by locking out the frequency. But usually, this noise will find it's way to another channel, causing me to lock out a lot of important communication. Now here are the facts. The frequencies the noise becomes attracted to are all VHF frequencies, with it's favorite on 155.160. The noise doesn't affect communications, but will prevent the scanner from scanning after the voice transmissions are complete. So my question is, What can I do to eliminate this noise?
Thanks in adavnce.

 

[scannerfreak]

Did you try using a PL tone for the Agency that uses that channel? I had the same problem on 155.685 and 154.200 and had to use a DPL tone on 155.685, and that corrected the problem.

 

[suttles1972]

Yes I did. It has a PL tone. I was given the impression that my problem is due to household or neighborhood noise. I have never heard of such, but with it occurring mostly at night, it doesn't surprise me.

 

[jim202]

Ifthe buzz your talking about sounds like wires arcing, you may have to look around some. Fish tank heaters are controlled by cheap thermostats. These cause all sorts of untold radio interference problems.

Another source is the bell transformers for the front door bell. These go bad and start acring between the windings. These are hard to find as many are located up in the attic someplace.

Then there is the electric power pole insulators. These are a little harder to pin down. You may have to drive around the neighborhood while listening to an AM radio. Try to pin point the general area where the noise is the worst. See if you can pin it down to one or two poles. Then call the power company.

I use to do this late at night. Didn't want to have anyone see me wacking the pole with a 12 pound sledge hammer to see if I could change the noise. The power company takes a dim view of people going around and hitting their poles.

Jim

 

[JamesO]

You probably cannot filter this out, you need to find the source and correct the problem.

It sounds like impulse noise, which is usually wideband in nature. The source is most likely very close to your antenna, within a few hundred yards. You might even see if you can hear it with an indoor antenna on the radio.

A handheld radio or scanner is a good tool for locating the source. Set the unit to AM at the freqeuencies you hear the noise, it will probably be more obvious. If you can get on the roof near the antenna, start there and work in circles farther and farther from the antenna to see if you can locate the source. A small directional antenna may also be useful.

Like the previous poster indicated, could be power lines, the power company usually has someone dedicated to solving this type of problem. But, do not call the power company until you know for sure that it is a power company problem and where the problem is located. Also consider neon signs, high Voltage lighting, motors for ventilators etc.

Temperature and humidity can also cause the problem to become worse. Usually morning or eveing dew on the power line insulators can generate more impulse noise.

Good luck locating the source.

JamesO

 

[jwood]

:x BPL???

 

[loumaag]

Another possiblity, since it seems to occur mostly at night, is those wonderful "touch" lamps. Those things are banned in my house.

 

[MetalManMI]

This probably isn't it, but an interesting article and may give you some ideas on how to track it down:

http://www.eham.net/articles/9045

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