Topband: Noise problem question

Jon Zaimes AA1K jz73 at verizon.net
Tue Dec 20 16:53:30 PST 2011


tnx info Dave ....where can those be had?

On 12/20/2011 2:30 PM, David Raymond wrote:
>
> 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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