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Re: Re: 2m to 70cm upconverter design, any interrest ??



Message text written by Andy Brian
>
Hi,
I know about that converter which was published in QST, the author was
KA9LNV.
The main problem for many of homebrewer were the local oscillator or better
the
crystal 101.875MHz, the  problem was to get them somewhere.
Maybe any suggestion to take any similar crystal?

best regards Andy<
-------------------

Hi, all:
        I bought the original crystals from JAN Crystals in Florida. They
were rather pricey even at the time (~$22, as I recall). I just looked on
their
web site and it is a bit difficult to determine if they will even do single
crystals 
any more. Down East used to carry them, but they aren't listed any more.
I have long thought that there must be some way to use standard
microprocessor crystals or oscillator modules in this sort of service. 
Unfortunately, 100 MHz is just not close enough to 101.875 to work with
a standard 30MHz top end IF rig. And you just can't pull them that far.
Good 
project for some RF guru.
        As note on alternate thinking, one of the HF radios I have used
with transverters
is a Kenwood TS-430S transceiver. Nice in that it has a transverter port.
Plug
something into that 5-pin DIN and it automaticallly disables the
transmitter
and supplies 5mW of Rf through the transverter port only. Now here's the
cool thing... although the transmitter will not transmit out of band under
normal
usage, it will give you 5mW of RF out the transverter port on any
frequency. 
Anywhere from 3 to 30 MHz. So, I crystaled transverters to be used on 70cm
so that the top end of the satellite band (436) would be at 30 MHz, and I
could
still use the weak signal portion (432) by simply tuning the TS430S to
transmit
on 26 MHz. Worked fine. I wonder how many other microprocessor-based
rigs will do the same? Now if I could only train the darn thing to transmit
above 30 mHz, I could use 100 MHz microprocessor stuff! Too bad.
        Re: the 2-part 70cm article that Dom I8CVS (who actually built and 
used one!)  and others have referred to... I can send a 3-part zipped .pdf
of it,
 where each part is small enough that most email servers don't choke on it.

73,
Ed K9EK 9ex-KA9LNV)
EM69xd
----
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