Duane has suggested:
> Nothing in those two sentences implies that the main
> RX will not be DSP based, in fact plainly says it will
> have DSP. I interpreted his comment to reflect that
> there will be a mix of analog elements and DSP in the
> IF chain. Much the same as Ten Tec's DSP radios to
> date already are. This makes good sense because 130+
> dB dynamic range A/D devices are rather rare or at
> least very expensive. I'm sure that much of the
> top-notch performance will come from choosing more
> capable analog devices in the RF/IF chain before the
> signal gets digitized.
The RX-340 manual lists manufacturer's part numbers for
the D/A and A/D converters, surface mount IC's, but
not a manufacturer's name. Part numbers are:
A/D on boaard 81790, AD7872JN
D/A, same board, AD7840JN .
Does this info tell us anything about the dynamic range
of these devices in the 340, if you can ID the manufacturer?
> There are several really low phase noise synthesizer
> chips out there already that rival crystals.
The synthesizer chip in the 340 is Motorola part
MC145170D1; is this the same as the Pegasus/K2?
The first LO in the 340 is a three loop architecture
synthesizer. There are two 10 MHz TCVCXO crystals
on this board (81772). They have manufacturer's
part numbers of VTXO14010G and the other
DFA20-HAV10MHZA1 if these part numbers will shed
any more light on what is going on, hi.
I could post the circuit description of the entire 81772
board from the 340 manual, if that would be of interest/
help to this discussion of what we might see in the Orion.
> Did you realize that the K2 and Pegasus/Jupiter share
> the same Motorola synthesizer chip? One has exemplary
> phase noise specs and the other is mediocre by today's
> standards.
73, Jim KH7M (and using the Pegasus/RX-340/N4PY system)
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