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Larry Larry is offline
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First recorded activity by BoatBanter: Jul 2006
Posts: 5,275
Default FT-857 vs 706 MkII ?

"Lynn Coffelt" wrote in
:

Of course, since the current node of a vertical did most of the
radiating, you had to get that current node out of the pilothouse (or
radio room) and out into the clear. (where, pray tell, is that on a
well rigged fishboat?)


Over on www.qrz.com put my call w4csc into the search box and bring up my
webpage. That insulator I'm holding in my hand was the bottom half of an
antenna feedthru insulator that fed 70KW on HF from the fish hold on an
old Canadian fishing trawler to a T cage vertical mounted between two
90' towers welded to the deck fore and aft. The T feedpoint was right on
the deck, offcenter about 20% of the flattop.

That little black mark down the side of this 360KV porcelain insulator
was what happened when they lit off the Technical Materiel GPT-40K inside
the fish hold. It fed the antenna from its 600 ohm open feeder output on
top of the cabinet with 3/4" copper tubing sort of in parallel. One of
the tubes simply ended 2' under the hatch this insulator was mounted
through and the other tube was bolted to the bolt at the little end of
this insulator. Here's a picture of the transmitter before Reverend
Stair of Overcomer Ministries bought it from VOA Greenville, NC:
http://hawkins.pair.com/voanc/voanc07.jpg
Rev Stair runs a religious commune out of some trailers in Canadys, SC,
and buys lots of radio time on WRNO and other shortwave broadcasters:
http://www.overcomerministry.org/
He's a scallywag and parttime sex offender:
http://www.christianmediaresearch.com/stair-01.html
http://www.clrc.net/brostair.html
http://www.freewebs.com/brotherstair/
http://home.bellsouth.net/p/s/commun...geid=21724&ck=
Jim Jones is alive and well in many places in South Carolina....(sigh)

The idea was they had permission to anchor the ship in international
waters off Belize and Belize would allow them to microwave relay
programming to the ship from Belize. The FCC used their little tests
from the Wando River shipyard as an excuse to confiscate everthing before
they could leave the country and try it.

I was standing beside the transmitter during the failed test. The
insulator was my souvenir...(c; The boat's captain was a ham from St
Kitts and had invited me aboard to show off. He wanted out of the
project because he was afraid the "brothers" were going to dispose of him
at sea as soon as he got the electronics running with his engineer.

Glowing blue inside the fish hold just before the flashover to the hatch
was most exciting. The whole place glowed blue from the intense RF on 41
meters just above 7.3 Mhz. The flashover didn't harm the massive
transmitter, at all. It simply tripped out on load impedance....(c;

All in good fun....Every flourescent tube at the boatyard lit up REALLY
BRIGHT, even though the little ship was anchored out in the Wando River.
It wasn't going to work. The intense RF current from the hull to the sea
was eating holes in the steel hull. First indication of that was when
the fresh water tanks in the bilge started tasting like SALT and filling
themselves. Attempts by Brother Stair's divers to weld up the holes the
RF was creating as massive electrolysis were proving unsuccessful. 70KW
into a 13 ohm feedpoint impedance creates an impressive current as well
as voltage nodes. The insulator is in my trophy case...(c;

Larry
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