Mike,
I use the SDR with the Delta 44 & Beringer 602 mixer to drive
a Henry 4K Ultra on 20 meters with no RF problem. However, the first time
I tried it on 40 meters I had a problem. I solved the problem by
disconnecting the other rigs from the mixer (I had a FT-1000D & FT-847
hooked to the mixer). Turns out RF was getting into the mixer from
the FT-1000D. I must have had about 50 lbs of ferrite chokes on all the
SDR lines. Today I have none.
Try disconnecting everything from the Beringer 802 except for the mic
input and line to the Delta 44 breakout box. Also, keep the
audio lines short and watch out for resonant lengths on the audio
lines.
Good luck.
73,
Bob
K8MLM
In a message dated 8/14/2005 11:20:45 P.M. Eastern Standard Time,
[EMAIL PROTECTED] writes:
Fellow
sdrmen,
Several of us are struggling with what seems to be a common
problem. All using the 100w sdr with the Delta 44 and breakout
box.
The ssb audio is distorted seemingly by rf getting into the sound
card and/or radio.
I have tried many and varied ferrites, various
forms of grounding, etc. Tonight, I connected to a dummy load, and
monitored the audio on a separate rx - an 775dsp set to 3.6 Khz
bandwidth.
Speaking into the mic, as I turn the power meter from 1 to
100w, I can hear the rf in my particular set up begin to distort the audio
at approx. the 20 w level. Under that, the audio is
presentable. Above 20w, the rf begins to show up and distort the
audio. I am using an EV RE27 mic and the Beringer 802 mixer to feed
directly into the Delta 44.
Several of us are working to find the route
and method the rf is getting into the audio. Seems to be a common
problem. If someone has found the secret, I would certainly like to
compare notes.
Thanks for any suggestions or assist. 73,
Mike K5NU
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