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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default A sea story, a reminder, and a parable (CAUTION: LONG)

Gordon wrote in
:

We decided to jamb him once. The radiomen rigged an antenna using a
rat guard to make it directional. Came alongside the trawler and turned
on the jambing for a minute or so. Turned it off and all we heard from
the fleet was "What in the hell was that?" Seems we killed everybody in
the Tonkin Gulf. I often wondered if the admiral ever found out who was
responsible.


Shipalt took our old AN/SPS-6A air search money pit off USS Everglades,
but we got them to leave the nice antenna mount hooked to the gyro system
with manual control. Metal shop and welders made a nice TV antenna mount
to fit it with slip rings so the TV cable had a coax rotary joint you
couldn't wind up. We bought a bright blue Winegard dual bay VHF/FM/UHF
monster antenna for it out of geedunk funds and installed more TV cable
system inside the hull for the crew.

We were, oddly for us, traveling slowly, the only speed we went, in a
formation of Navy ships in the Med near the Italian/French border. I
don't remember how far offshore but it was way over the horizon. The
Russian trawler showed up, and I notice them taking pictures of our
pretty TV antenna and reported it to the OOD. Captain Tidd was the CO
and he used to come down to my cal lab to use my ham gear for phone
patches to his wife back in Charleston. He knew me, a simple ET1 at the
time.

"Is there any way we can put some kind of signal out and rotate that
antenna to look like it is radiating?", he asked me on the bridge I'd
been summoned to. There was. I had an RF Power Pulser to calibrate
pulse reading wattmeters up to several kilowatts, peak power, back in my
lab.

I rigged up the Power Pulser into some heavy coax and the lowest
frequency feed horn I could find. I called the electric shop and got a
box of powdered carbon for a dummy load. There was a light lock hatch
sort of under the antenna where I could sit, unobserved from the trawler,
and someone on deck could tell me when the TV antenna was pointed in
their direction. I set the Pulser to the bottom end of the feedhorn's
bandwidth, full power about 4KW peak and held the feedhorn in the box to
absorb the radiation. Each time the TV antenna rotated around towards
the trawler, I pulled the feedhorn out of the box and pointed it at them
out the hatch, briefly, then put it back in the carbon. After putting it
back in the carbon, I'd change frequencies (wifi 1966) and pulse width
and repetition rate before it swung around again....great fun.

The effect on the Russians was profound! Important-looking people showed
up on deck with more cameras taking pictures of our big Winegard secret
weapon and I'm sure my Power Pulser was showing up on ELINT equipment in
the hold to be taken back to Moscow for evaluation. This went on for a
couple of hours before someone coordinated the "secret weapon shutdown
sequence" where I turned off the RF while the guys on the bridge turned
off the rotation. Satisfied they'd had the tapes, they soon left. The
diversion allowed other important ships to do things, unimpeded by the
fascinated Russians.