A few people asked for a recording of the noise, which is posted here:
https://m.youtube.com/watch?feature=youtu.be&v=Hht3peCne9Y
Regards , Kenny K2KW
> On Jan 8, 2020, at 7:46 AM, Don Kirk <wd8dsb@gmail.com> wrote:
>
>
> Hi Ken,
>
> One last comment or clarification. I do agree that looking at the audio
> signature ahead of time is useful to help decide if the noise looks like
> power line type noise as that provides a clue about my 136 MHz AM tracking
> equipment being useful or not.
>
> Therefore I would indeed like to see the .wav file you mentioned when you
> obtain it. Make sure you record in AM mode using wide filter.
>
> 73,
> Don (wd8dsb)
>
>> On Wed, Jan 8, 2020 at 7:31 AM Don Kirk <wd8dsb@gmail.com> wrote:
>> Hi Ken,
>>
>> I helped W9TC locate a street light that was causing interference on HF that
>> sounded just like power line noise. Noise only during hours of darkness,
>> and it was on continuous. The bad light pole had a bulb that appeared to be
>> burned out (it never illuminated). The audio signature was similar to what
>> you see from power line noise (120 Hz), and I was able to use 136 MHz AM to
>> confirm the light pole was the source. Don't know what the problem was with
>> the light pole, but the property owner had the light repaired, and problem
>> went away. The light pole was located 560 feet from W9TC antennas.
>>
>> I really don't think you should be thinking about anything, other than using
>> good direction finding techniques to locate the source. You need to use
>> direction finding techniques to identify the property where the noise is
>> originating, and then identify the culprit device, not the other way around
>> (just my stead fast opinion).
>>
>> Just FYI,
>> Don (wd8dsb)
>>
>>> On Wed, Jan 8, 2020 at 6:52 AM Kenny Silverman <kenny.k2kw@gmail.com> wrote:
>>> Thanks for the replies so far. Just to reiterate, the noise is only from
>>> sunset to sunrise and it’s constant. So it’s likely lighting related, but
>>> it doesn’t cycle. Have there been examples of constant noise from street
>>> light or should we be thinking more about store signage?
>>>
>>> Regards , Kenny K2KW
>>>
>>> > On Jan 8, 2020, at 3:47 AM, Don Kirk <wd8dsb@gmail.com> wrote:
>>> >
>>> >
>>> > 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
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