No Steve you are wrong. There is side band inversion. I was there.
Look at it this way. say you have a carrier at 9.000 and a tone at
9.0015. Subtract 5.000 for 80 meters, the carrier comes out at 4.000 and
the tone comes out at 3.9985, LSB. Add 5.000 for 20 meters, the carrier
comes out at 14.000 and the tone at 14.0015, USB.
Its NOT folklore or myth, its the truth. AND IT IS THE REASON FOR THE
SIDBAND CONVENTION we have today and that is fundamental to the Corsair
and Corsair II normal sidebands because they use they same mixing
schemes as did many Tentecs before them. In the OMNI VI they arranged
all the LO injections to be on the highside, but CW to be only on LSB so
it runs CW on LSB on all bands. With solid state switching some of the
anomalies were taken out in the control logic that are not so easily
changed in the Corsairs because mode switching is a ganged switch.
73, Jerry, K0CQ
On 4/16/2011 1:00 PM, Steve Hunt wrote:
Jerry,
I never understood that piece of Ham folklore, or should it be "Ham Myth" :)
In a mixing arrangement comprising a 9MHz IF and a 5-5.5MHz LO, designed
to cover 20m/75m, there is *NO* sideband inversion between the IF and
the RF. A USB signal generated at the 9MHz IF would become a USB signal
on 20m and also a *USB* signal on 80m.
So, simplification of the sideband generation or detection for that
simple mixing arrangement cannot be an explanation for the sideband
convention we have today.
73,
Steve G3TXQ
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