[TenTec] Orion prototype

[Jim Reid]

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)