RadioBanter - View Single Post

November 15th 04, 06:02 AM

On 14 Nov 2004 03:15:13 GMT, (Michael Black)
wrote:

matt weber ) writes:
On Sat, 13 Nov 2004 07:20:09 GMT, m II
wrote:

Is the Superheterodyne set over rated?
Useful Bandwidth control and true synchronous detection are things you
cannot do with a Regen. Try receiving SSB or FM with a Regenerative receiver.

You most definitely don't need a synchronous detector for SSB reception;
Actually you are taking that out of context. Synchronous detection is
useful only for AM, and a Regen cannot deal with selective fading any
better than a standard envelope detector can.

The fact is however, that synch detection is unavailable on a regen,
because you need to phase lock to the original carrier. In theory a
Regen can handle SSB, in practice it cannot due to lack of a stable
carrier, lack of a product detector, and inadquate sensitivity. YOu
can get SSB without a product detector, as long as the injected
carrier is very large relative to the SSB signal so the envelope
detector is operating in a linear part of the V/I cure. NB fm can be
slope detected, standard FM cannot, it is much too wide for slope
detection work. NB FM is mathematically the same as AM with a low
modulation index.

Synch detection isn't much good for FM.