Hi Everyone,
I have a dumb question...
I have an RFI problem on 20 meters when I connect my soundcard to the
audio in and audio out jacks on my Omni VI +. I have grounded both the
computer case and the transceiver with short direct ground wires to the
common ground point (8 inch strap for the computer, 24 inch for the
transceiver).
If I unplug the phone plugs from the back of the rig the RFI hum goes
away, when I plug them back in the noise is back.
I bought a couple of audio isolation transformers from RS (273-1374) but I
can't get them to pass the audio signals. I soldered the White wire to the
center conductor on jack #1 then the Black wire to the jack #2 center
conductor. I then soldered the Yellow wire to the ground tab on jack #1 and
the Red wire to ground on jack #2.
I used a non-conductive box since I didn't want the audio grounds from
input and output to mix (I figured this would defeat the isolation part).
No audio passes through when soldered this way and there is only
continuity between center conductors when measured with a VOM. I have three
of these "isolators" and so far all they're good for is isolating the audio
signals from between the rig and the sound card.
Can one of you tell me what obvious, dumb, "I should have remembered
that!", mistake I'm making?????
I want to get on for the contest part-time this weekend (I'm on-call this
weekend so it will really be part-time) and I haven't ordered the new
motherboard so I can do FSK (Longer Story, don't buy a FIC Athlon
motherboard!!!!!) so a fast answer would be appreciated.
Thanks everyone,
George / KF9YR
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