Has anyone successfuly extended a buffered I.F. sample point from either the
9 MHz or 6.3 MHz I.F. stages out to the back of the Omni Six? I intend to
sample the receiver's I.F. on an oscilloscope with the intent to monitor CW
and SSB wave forms. At this point, it would appear the best point to
accomplish this is through a 100pF coupling capacitor off of Q1 on the PBT
board. The output of Q1 is the post 9MHz filter I.F. as it enters into the
PBT board. Sampling downstream after the 6.3 MHz I.F. may introduce too
much distortion (through cascaded filters) to critically evaluate received
waveforms and hence the 9 MHz point after an INRAD 2.8 kHz filter appears to
be ideal. Then, a short run of RG-174 could be used from the sample point
out to an existing RCA jack on the rear panel. The "13.5V aux" jack appears
to be one I'll never need. Too bad there's not a designated "spare" jack as
Ten-Tec provisoned on the Pegasus. If isolation or leakage appears to be
problematic, a simple "N" channel FET configued as a voltage follower could
be placed adjacent to Q1 on the PBT board. Comments?
-Paul, W9AC
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