Thanks Dave! This looks like a great tool.
Regards , Kenny K2KW
> On Jan 8, 2020, at 10:02 AM, Dave Cole <dave@nk7z.net> wrote:
>
> Download S-Meter Lite, and run it for at least week or more, more is better,
> watch the start and end times of the RFI. If they stay rock solid, the
> problem is probably on a timer, if they are shifting with sunset/sunrise, or
> bobbling around by a minute or more, then it is something controlled by
> light...
>
> The key is to note the start times to the second. S-Meter Lite allows this,
> with repeatability. The sunrise time should be creeping earlier. This will
> take a week or so to see at least... If the start time is moving around,
> then it is probably not on a timer.
>
> Read the instructions for setting up S-Meter Lite to capture to a file... It
> is not intuitive...
>
> 73, and thanks,
> Dave (NK7Z)
> https://www.nk7z.net
> ARRL Volunteer Examiner
> ARRL Technical Specialist
> ARRL Asst. Director, NW Division, Technical Resources
>
>> On 1/7/20 9:08 PM, donovanf@starpower.net wrote:
>> Hi Kenny,
>> The RFI you describe certainly appears to be triggered by sunset,
>> either a streetlight or one or more outdoor lights in a residence.
>> Night time only RFI is extremely rare on power lines.
>> You've got the right idea about how to track 160 meter RFI. A loop
>> antenna will provide excellent directivity and will immensely valuable.
>> As you get closer to the RFI source you should be able to go up in
>> frequency, ultimately to perhaps 450 MHz. But not always...
>> Some RFI sources do not produce much energy at VHF and above.
>> Two of my most eggregious RFI sources were exactly that way. One
>> was an electric fence charger that failed continuously on (no pulsing)
>> and produced RFI only below about 2 MHz. The other was a
>> Highway Advisory Radio Station with a failed synthesizer that produced
>> S9+ broadband RFI all over the 160 meter band b ut nothing above 2 MHz.
>> Good luck with the hunt!
>> 73
>> Frank
>> W3LPL
>> ----- Original Message -----
>> From: "Kenny Silverman" <kenny.k2kw@gmail.com>
>> To: rfi@contesting.com
>> Sent: Wednesday, January 8, 2020 4:55:11 AM
>> Subject: [RFI] Quidance on finding noise?
>> 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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