Jon. . .great advice, particularly about going to higher frequencies as you
get closer to the noise source. We've spent considerable time chasing noise
at our contest station. I addition to using RF we also use a high range
audio device with a highly directional dish antenna which listens in the
20 - 40 KHz range. It is an excellent tool to have in the arsenal when you
get in close (say, 100 yards or so). You can usually pinpoint the noise
right down to the specific insulator, lightning arrestor, etc. In some
cases it would be worth borrowing one.
73. .. Dave
W0FLS
> Dave,
>
> I use my mobile rig to track down such noises (an IC-706Mk2G with a KJ7U
> 160-6m screwdriver antenna and 2/440 whip). I also have a couple of
> small AM and VHF-AM (aircraft band) portable radios when needed.
>
> The closer you get to the noise, the higher in frequency you should be
> be able to hear it. Sometimes I'm up to 300-400 mhz before I can zero in
> on the exact pole that is the source after driving back and force in the
> general area. Beam headings from the house can help with the initial
> zeroing-in.
>
> I make note of the pole number -- there are tags about eye level -- and
> then notify the utility. Here I have two that overlap in this area, and
> I've found the guy responsible for RFI issues in each and report it
> directly to him. They usually appreciate I've done all the legwork and
> get it fixed in short order.
>
> 73/Jon AA1K
> www.aa1k.us
>
> On 12/18/2011 2:36 PM, W5UN wrote:
>> I'm looking for input from someone who has experienced a similar
>> situation as I describe below.
>>
>> About 3 months ago I began experiencing severe noise on top
>> band. It's a constant white noise which begins to drop off above
>> 2.5 mHz, and is hardly noticeable on 80, and not there at all on 40
>> meters and above. Every once and a while the noise will drop off
>> completely, only to return a few minutes later. It is there about 98%
>> of the time.The severity seems to vary a little, but is typically
>> S9+15 db when present, and S3 during the rare times it drops out..
>> This noise is coming from the eastern direction, about a mile from
>> here. There are power lines.there, and these appear to be the source,
>> however there are similar power lines of the same voltage here in
>> other directions, including one to the southwest about 800 feet away,
>> but that one has no noise. Has anyone experienced such noise as this?
>> I need to see if I can track this down and get it fixed. Any help
>> will be appreciated.
>>
>> Dave, W5UN
>>
>> _______________________________________________
>> UR RST IS ... ... ..9 QSB QSB - hw? BK
>>
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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