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Drake 2880 Downconverter

Message text written by INTERNET:brisch@qwest.net
I have a question for those of you who have already converted the Drake.
I have one that I have not converted yet but have (most of) the info for
converting it.

I would like to know if it is possible to make the downconversion to 420
by substituting another crystal.  I have no info on the oscillator
circuitry in the downconverter and do not know its limitations. Could a
7.??? Mhz xtl be used.
While I am experimenting I, also, am giving thought to driving that circuit
with a DDS source allowing me to move the frequency at will.  

Just ideas that I would like comments (pro and con)  on and any suggestions
from those who have made the conversion.

Bill K0QK<

        Convert the Drake 2880 to a 70 cm IF? Heavens, yes! It's the
easiest, cheapest conversion of all. The LO multiplies by 256. Use a 7.65
MHz microprocessor crystal (about $1.29). Mine gives a 1966.08 LO, so I get
2401 = 434.92 MHz. Don't bother to do the IF conversion, since 434 MHz is
within the specified IF bandwidth. Replace the crystal, make it run, button
it up and go. Nothing to it and it works like a charm.

Ed Krome K9EK

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