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Re: TRAN-SYSTEM converters



JAN has 'em, courtesy of K5GNA.  Briefly, they are:

Fcrystal = (Frf - Fif) / 256, fundamental mode, parallel resonant (19 pF
load capacitance), 10 ppm drift, ambient temperature, HC-49/U holder.

So, to convert 2400 MHz to 144 MHz, you need a crystal frequency of
8.8125 MHz.  Other than that, this is NOT the same as a Drake 2880
crystal.  Different case, different load capacitance.

I'll defer to Bob for clarification, if necessary.  He was trying to use
a 60 deg. C PTC to help stabilize the crystal, but I believe that he has
since decided that there are too many other sources of thermal drift in
the oscillator circuit to justify the PTC's added cost and complexity.

regards,

Mahlon - K4OQ

Don Woodward wrote:
> 
> I'm new to satellite and am in the process of building my station. I bought
> one of the TRAN-system corner reflector units on eBay a while back - does
> anyone have the crystal specifications/modifications finalized on how to
> move the output to the 144 range? I'm real anxious to listen to AO-40
> directly rather than through one of the audiocasts.
> 
> Also, I have several spare oval DSS dishes - I was considering mounting it
> on one of those later - has anyone tried that yet?
> 
> Don Woodward
> KD4APP
> AMSAT 33535
> www.sunsunsun.net
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