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Qualcomm Synthesizers for 2256 MHz LO (144 MHz IF for 2400 MHz Rx)

Well,  I got the bug last evening  and  just to show how easy it really is
to put together a  Qualcomm surplus synthesized LO for 2256 MHz (144 MHz IF
for 2400 MHz Rx) I converted one.  It took me about 1 hour from digging out
a board through checking it out on a spectrum analyzer & included time to
kick my wife off of the computer so I could run the Excel spreadsheet which
does all of the calculations including indicating which pins are to be
lifted or grounded. I also found a couple of mistakes and added a 0.5 pf
cap to lower the VCO frequency range slightly in that time .  I don't
expect anyone else to be in a position to do it quite this fast but it
should give an idea of how easy it is if I can work out the procedure on
the first unit & have it operating in an hour.  I'll be talking to Dave
Guimont about helping to distribute these synthesizers as well as some
pieces to build 2400 MHz markers. BTW - These same synthesizers can be
programmed to produce 2400 MHz as a not so weak signal marker (about + 10
dBm out). The PLL chips have the capability to be either parallel
programmed (the mode I use them in by lifting pins) serially downloaded. We
also have plenty of teh 10 MHz TCXO's to go with them (same as themany
TCXO's that were ditributed at the 1999 AMSAT Convention here in San Diego)
 - Kerry N6IZW -
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