"Steve Nosko" wrote in message
...
Steve's imbedded comments:

"Avery Fineman" wrote in message
...
In article , "Steve Nosko"
writes:

What's the essence of an AM sync detector? Extract the carrier
(filter/clip/amplify the bajeebers out of it) then product detect the
sidebands ? Steve N, K,9;d, c. i My email has no u's.

...locking a local mixing oscillator to the carrier frequency and
mixing that with the whole thing.

Ah yes! need a reliable LO.


Absolutely not. In a homodyne receiver, it's only necessary to recover
the carrier by way of a limiting amplifier.


... A carrier in-phase lock allows separate
detection of the sidebands...which could be used to
advantage such as having binaural audio modulation with AM.

Ah yes... Back to the old three methods of generating / detecting
sideband signals.


What's being suggested here is a synchrodyne receiver, where an
oscillator is locked to the carrier of the incoming signal. This requires a
Costas loop and is not at all necessary for simple AM detection. A homodyne
is sufficient.

Chris

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