There are two problems on 17m with the Omni C. The IF is 9 MHz, so the
LO is mixed to 9 MHz also. Twice the LO injection is 18 MHz, twice the
IF is 18 MHz, both roar through the mixer to produce spurs on transmit,
whether SSB or CW. The Local Oscillator is the main problem. Later
radios mix the LO to the high side which cleans up the spur but makes
their standard sideband inverted on the 17m band.
73, Jerry, K0CQ
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Entire content copyright Dr. Gerald N. Johnson, electrical engineer.
Reproduction by permission only.
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