Kenny,
I should also mention that I did have to track down noise from faulty light
pole (problem only between sunset and sunrise), and same setup I use for
power line noise worked great to find the suspect light pole. 136 MHz AM
in close again was necessary to pinpoint the pole that was in a commercial
parking lot. (Distribution/trucking company parking lot).
Don (wd8dsb)
On Wed, Jan 8, 2020 at 3:38 AM Don Kirk <wd8dsb@gmail.com> wrote:
> Hi Kenny,
>
> I normally use portable HF radio with portable tuned loop and preamp on
> 160 or 80 meters to triangulate on power line noise and then back the RF
> gain down as I get close and sometimes use my car radio on 1710 KHz to
> locate potential areas. I also have 3 pennant RX antennas at home that
> each point about 120 degrees from each other that let me know the exact
> direction from my QTH the problem is coming from which really helps get me
> started if I’m working on issues at my QTH versus another hams QTH.
>
> Typically using portable AM receiver (portable police scanner) on 136 MHz
> and 4 element hand held beam with elements lengthened for 136 MHz I
> typically hear power line noise at least 0.2 miles from the arcing power
> line pole and sometimes greater distance. When I’m in close (when I can
> see the suspect pole) I normally have to throw in 20 to 30 db of
> attenuation to pin point the pole.
>
> The arcing power lines I have located have typically been 1.25 miles away
> or less.
>
> To pinpoint the pole I have to use 136 MHz AM with lots of attenuation
> (not HF).
>
> 73.
> Don wd8dsb
>
>
>
>
> On Tue, Jan 7, 2020 at 11:55 PM Kenny Silverman <kenny.k2kw@gmail.com>
> wrote:
>
>> Hi and thanks in advance!
>>
>> We’ve been trying to track down some noise at a friends house but no luck
>> so far and I was hoping for some tips on finding it. The buzz comes on at
>> sundown and turns off at sunrise. It’s bad on 160 but it can be heard
>> Lightly on 80 and 40. The noise is constant and does not cycle (at least
>> for the 90 minutes I was listening to it tonight). The worst direction is
>> on the East beverage on 160. On 80m it seemed like the worst was to the
>> NW... it could be 2 sources but the noise appears to come on at the same
>> time in all directions, not a staggered turn on/off. Could be a single
>> source but poor F/B on the beverages. The Listening to the ARRL RFI files
>> it sounds like power line noise or street lamps ( but without the
>> cycling). Over the 90 minutes tonight there were almost no variations
>> (except for an occasional change in pitch).
>>
>> We've DF’d on a portable AM radio, 2m and ultrasonic device. AM
>> identified some noisy poles but we’re not convinced these are the main
>> offenders. Not much luck with VHF or ultrasonic. Our next plan is to use
>> a KX3 on 160m and a decent RX loop to direction find and triangulate.
>>
>> I suspect we’re not looking out far enough... suggestions on how far
>> away we should be looking? And how close do we need to be to hear it on
>> VHF?
>>
>> Besides power lines and street lamps, other thoughts on possible
>> offenders? Most of the area is residential with street lamps on most
>> streets.
>>
>> Regards , Kenny K2KW
>> _______________________________________________
>> RFI mailing list
>> RFI@contesting.com
>> http://lists.contesting.com/mailman/listinfo/rfi
>>
>
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