[Boatanchors] Peristent, annoying, intermittent, elusive QRN problem: help please!

[Will White]

I have a local noise problem I am hoping someone can help me track down.  I hear

S-6 or 7 loud, 'coarse' has on all HF bands, on all frequencies, though the
intensity of noise diminishes somewhat on higher bands.  On 40M, my main band,
it is all but intolerable, making QSOs with all but the loudest stations
difficult, even at 12 WPM or so.

The noise comes on for exactly 2' 15", and goes off for exactly 1' 25". Over and

over. I have timed it many times over two weeks.  The noise is only there after
dark. Aha! But I have searched and searched for an intermittent streetlight, to
no avail. I have gone about three blocks in all directions from the house in
this search, and also looked for automatic driveway/porch lights nearby, but
can't find any. What the &*%$ can this be!??  I am really puzzled by the exact
timing, since it would seem that a streetlight malfunctioning wouldn't do this,
and a driveway light might stay ON for a specific time, but not off! HELP!



--
Will White, KD7BFX
Seattle WA US
King County, Grid CN87tq
ITU Zone 6, CQ Zone 3
***************************************************
"The wireless telegraph is not difficult to understand.
The ordinary telegraph is like a very long cat.
You pull the tail in New York, and it meows in Los Angeles.
The wireless is the same, only without the cat."
                                                      - Albert Einstein
***************************************************