amdx wrote:

...Is it possible to have a high Q LC front end at the output from the
antenna,
split the signal and feed one output to the rf input of the mixer and feed
the other splitter output to an amplifier and use the amplified signal to
drive the osc input of the mixer? ...

the idea is not new (a few decades ago it was called "carrier
regeneration", and has been extensively used in synchronous demodulation
of AM and DSB, VSB and SSB with partially suppressed carrier), but you
need at least a residual carrier.

In the case of SSB, although carrier suppression is far from perfect,
filtering and amplifying the residual carrier up to an usable level is
not impossible, but definitely far from easy...

Speaking about CW, recovering the carrier is very easy (a simple PLL
with a very slow time constant would do the trick), but the next step
should be displacing said recovered carrier of a useful amount (say,
600-800 Hz) to give a beat note, and this is not so easily done.

Regards,
--
73 es 51 de i3hev, op. mario

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