Comrades,
The KAT100 Manual suggests that if a control cable between the tuner
and the K2 needs to be longer than about 2 feet, it may need to be
better shielded. My continuing struggle with RFI, in a system where
the 23 foot veritcal whip antenna feed and rfi ground meet at the rear
of the kat100 tuner which is located about 4 feet from the k2 leads me
to want to imporove this cable.
I had used the shielded multi-conductor which came with the KPA100 to
fabricate a control cable about 6 feet long with the pc interface
pigtail maybe 2 inchs long. Initially this setup worked great on 80l,
40,and 20 meters at 100 watts. Then, while tidying up the installation
to better suit the XYL, I somehow changed something which allowed rfi
on 40 meters to invade the system at any power level much above 12
watts. We found that by coiling the control cable as much as possible
given its length and the distance required to reach the tuner, that I
could transmit on 40 meters up to 50 watts without a lot of rfi
feedback.
I have a radioworks isolator between the tuner and the k2 and a whole
lot of ferrites on the control and power cables to the tuner. Power to
the k2 is also beaded throughly. K2 is grounded separately.
So the question is, what should I ask for to get better shielded
multiconductor than that which shipped with the kit which by the way
looked good to me.?
It likely doesn't make much sense to try to help me trouble-shoot the
installation since some of you have already given me a lot of very good
ideas. I think I know what the variables are and will have to go
through them one at a time and make certain that nothing has changed or
if it has, fix it. Or there is nothing stupi lurking in there
73, John Fergusoin KI4NGH
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