Hi,
I had an RF feedback problem with my Omni-VI+ for three years. It just
kept getting worse. I tried all the usual fixes and some inside, like
making sure all the internal plugs were tight, and adding a cap across the
mike connector. I used isolation transformers in the audio in and out,
opti-isolators to key it, RFI chokes, all shielded wires. Some helped, but
it just wouln't go away. It was worse at field day where I didn't have a
good external ground. It even got to the point where I was getting RF
feedback while in CW. I even thought the finals were oscillating. It got
so bad I couldn't operate any mode, so I sent it to the factory. They
fixed it, but wouldn't tell me what they did when I queried them. I asked
if it was a modification, and the technician I queried said it was.
:-(
Chas, W1CG
At 08:36 PM 9/10/2004, Jim Miller WB5OXQ wrote:
I wonder if you have a grounding problem. I run sstv using my omni6+
connected to my pc and no problems even with the amplifier on running 500
watts. I use home a home brew keying device connected to a serial port on
the pc with 1 transistor and 2 resistors to the key jack. Never had any
problems. I have used a cw keyboard and psk32 using the same stuff with no
problems even with the centurion driven near max output. You must have rf
floating in the shack somehow. i do not have any kind of rf blocking
devices on my cables either.
----- Original Message -----
From: "George Allgood" <w4gfa@bellsouth.net>
To: <TenTec@contesting.com>
Sent: Friday, September 10, 2004 4:14 PM
Subject: [TenTec] RF
> I'm having RF attacks. My OMNI VI+ with computer wired to the Key jack
swamps when I strike a key on the keyboard.
> The problem goes away if I reduce power on the OMNI to about one half.
It's a problem trying to use contest programs
> to key the rig. Anyone have a source for high quality, shielded cables
and connectors for this purpose?
> I've placed Ferrite cores on each end of the existing home brew cable,
but no cigar. Any suggestions would be most
> welcome.
> George W4GFA
> _______________________________________________
> TenTec mailing list
> TenTec@contesting.com
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>
>
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