On Sun, Aug 11, 2019 at 8:07 PM Don Kirk <wd8dsb@gmail.com> wrote:
> Hi Roger,
>
> Here is what I would suggest. I would make a 1 or 2 inch diameter single
> turn un-tuned loop antenna. Connect it to a portable HF receiver, and use
> the loop antenna to see what circuit breaker or breakers appears to be
> producing the strongest signal. Then you can turn on and off breakers to
> figure out what circuit is the real source of the noise. Typically if you
> turn off a breaker not related to the noise but that acts as an antenna you
> will hear the signal level change but not disappear. Turning off the
> breaker powering the noise generating device makes the noise totally
> disappear (you may even hear the frequency change slightly as the device
> powers down and/or up which lets you know it is absolutely the real culprit
> circuit). Here is a link to a youtube video I made last winter showing one
> of my small loop un-tuned loops in action.
> https://www.youtube.com/watch?v=UqLQ-mmUrVA
>
> The video is brief as the temperature was around 10 deg F and we were
> outdoors, but it shows you how simple it can be.
>
> I make my single un-tuned loops using RG-58 U coax, and they are extremely
> easy to make. Below are 3 of my small Un-tuned loops and they all work
> just great. If the picture below does not make it to you let me know.
>
>
>
> 73,
> Don (wd8dsb)
>
> On Sat, Aug 10, 2019 at 4:03 PM ROGER STEPHENS via RFI <rfi@contesting.com>
> wrote:
>
>> Listmates - after 60 good years in our hobby with more than enough rfi
>> sniffing and eventually eliminating I have met my match. I ventured
>> yesterday into my infirmed and mideighties afghan neighbors home which is
>> producing a roughly 25-30 db hash above my noise level on all bands.
>> After
>> a complete house recon, I still could not locate the source with my trusty
>> grundig yachtboy since the whole house was so hot (rfi can be heard from
>> several hundred yards away) that I could not discern a specific culprit.
>> The owners who were a bit confused by my endeavor and our language
>> challenges said that nothing had changed recently except when a bathroom
>> was
>> remodeled, the handyman replaced numerous wall outlets. So after more
>> chat
>> effort, I shut down the house mains and the noise disappeared so I know
>> the
>> gremlin(s) is hiding within. Not overstaying my welcome, I begged
>> forgiveness for the fruitless invasion but assured them I must come back.
>> My plan so far is next visit to shut down each circuit at the fuse box
>> till
>> the noise is isolated and then attempt to sweep that area of the house.
>> Since my detective work must be short time wise and the rfi is so strong,
>> what possible source might I look for and hopefully be able to unplug
>> knowing that it pulses 30 times a minute continuously and sounds like
>> arcing
>> to me with an audible preemptive spike at the beginning of each hash. It
>> begins as low as 85 khz and continues to pulse up to around 3 mhz where it
>> gradually becomes a continuous noise all the way up to 6mtrs. I trust
>> that
>> some of you reading this postmightl have some guidance to share as I
>> really
>> do miss being able to hear both my modern rigs as well as the fleet of
>> aging
>> boatanchors. J 73 es bye4now, roger k5vrx
>>
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>>
>
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