[Milsurplus] DFing receiver LO emissions (J. Forster)

[J. Forster]

>
>> From: "J. Forster" <jfor at quik.com>
>> > Small universal electric motors make a LOT of broadband noise. Couple
>> that
>> > with hundreds of shavers....
>> >
>> > Not that idiotic,
>> >
>> > -John
>
>
> John, I think the problem here is that a hundred electric shavers
> operating at the
>
> same time on a ship, are not coherent energy, in terms of frequency and
> phase.

I NEVER said they were operating at the same time. Clearly they were not.
Nore did ever imply the sum of all those shavers might combine in ANY way.
They are broadband, essentially random, noise sources.

> Think about a carbon arc light used for AA sky spotting. I don't think
> 15,000
> flashlights pointing at the sky would provide the illumination needed.
>
>
>
> Harold Goates of Gloversville, NY, may he be in peace, worked at some
> telegraph
>
> office in WW2. He was occasionally engaged by FCC for specific
> investigations.
>
> He told me they contacted him about a mysterious signal heard out to sea,
> maybe
>
> out to 400 miles off the Atlantic coast. It was feared this was some kind
> of beacon
>
> or signal.  After driving around for a few days they
>
> came to an upstate farm from where the signal seemed to be emanating. When
> they
>
> approached the resident, he seemed very nervous. But it turned out that an
>
> electric fence charger there, was the source of the signal. ( Reminds me
> somehow
>
> of "On The Beach" movie ). Harold guessed that the actual reason for the
>
> landowner's unease was that he was poaching deer and selling the venison.

Any spark is essentially an impulse source, and putts out RF from almost
DC into the uwave region.

> Harold attributed the range of the signal to the earth there being highly
> mineralized due to iron in the ground, something like that.

More likely the 1000' plus antenna (the fence)

> -Hue Miller

Best,
-John

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