> Today, I got a response from Scott Robins at TenTec to a question
> regarding "phase locking" the ORION's receivers. Here is his
> response:
>
> > You don't have to do anything for diversity reception. Merely push
> > a
> button on
> > the front panel to assign both receivers to a single VFO and start
> > tuning
> around
> > the band with one or the other of the main tuning knobs (you can
> > assign
> both
> > receivers to either of the two VFO's). Mix the audio any way you
> > want - separate rxers in each ear, both in one ear, both in both
> > ears.
> Put
> > each receiver on a separate antenna. With Orion, you can even run
> > each receiver to separate Beverages, then transmit on a 3rd antenna.
> > We've
> tried
> > to make it as flexible as possible
The question must not have been worded correctly, because Scott
answered everything but the phase question.
For everything but AM reception the question is...."Do the receivers
share the same local oscillators for all mixing and detection
stages?"
If the answer is no, then the next question is...."Are the
oscillators that are not common to both receivers directly phase
locked with a system that always keeps them locked to a common
timebase?"
If the answer is "no" to both, diversity performance is seriously
limited.
Also, if receiver phase delay (mainly group delay in filters versus
frequency) is not matched it will either ruin or damage combined
audio (mono) performance. Stereo would still work in most cases.73,
Tom W8JI
W8JI@contesting.com
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