On Wed, 31 Mar 2010, SC Dxing wrote:

Bruce,

My G5 can do SSB but it's via a fine tune knob. Not separate USB/LSB.
I can't really complain about the G5, I think I just want a new toy to
play with.

But that's not some different technique, it's just cheaper.

it's cheaper to have a variable oscillator as the BFO than two crystals to
allow for a fixed BFO that is properly placed for upper and lower
sideband. Crystals cost money, the tuneable BFO is cheaper and allows
for a level of fine tuning (though once you use it for fine tuning, you
lose the ability to place it right where it should be on the slopes of
the IF filter, but with a tuneable BFO you'd only be guessing anyway).

In both cases, there is a BFO. Some people seem confused by that, since
in the old days of a tuneable BFO, the knob was labelled BFO, but once
sideband receivers came along with crystal controlled BFOs, the knob
was labelled "mode" or "sideband".

With a sync detector, you need a tuneable BFO anyway to lock to the
incoming signal, so there's little sense in tossing that out for a
crystal controlled BFO for SSB reception.

Michael