At this stage of the game I've graduated to 'plug and play' RF electronics,
thanks to Mini-Circuits and like parts, all available for a song on E-Bay.
The IC706 made many trips so sea and was most useful as a duplex CW
transceiver on the marine CW and SITOR frequencies, and it is so old as to
be almost serial #1.
The picture @ this link shows a scheme for 10kc-510kc transceive. It is most
self explanatory with the only hidden info is that I cut the B+ lead to the
final of the IC706 and so by magic the RF output level @ 10.500 mhz. dropped
to 7 milliwatts, talk about luck and a happy mixer.
www.radiocom.net/600M/TxVerter2.jpg
The QRG is held to tight specs by use of the GPS diciplined clock 10mhz as
the LO input to the DB Mixer.
On 500kc. I use the modified Ramsey 1W amp shown, followed by a modified
200W Mitsubishi stereo amp with giant 900V FETS, and thence to a modified
SB200, now designated as a SB600M. The Greenlee punches around here are all
dull and old, so why start from scratch any more??
Rework of junk commercial and military boxes is now the caper.
www.radiocom.net/600M/SB600M3.jpg
And here is the best TX antenna I have used so far here, free of any ground
radials and many top load wires hung up in trees, but only meant for really
poor soil conductivity mind you and that is < .5 millimho here on silica
soil. Always wondered how it would be to have an antenna in 'free space'.
It amounts to a 65' vertical of #4 wire inside garden hose and laid over
high pine trees. A free extra is that the loop is certainly more quiet than
the Marconi vertical. It also works DX up to 6M so we took all the other
wire antennas down. Life is getting simple, so we do.
www.radiocom.net/600M/Loop1107.jpg
Too much fun and not enuf air time!! Even had a SKN QSO on 600M, ham radio
is still fun...
Regards to all,
Dave@WD2XSH/17
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