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Old November 1st 04, 02:20 AM
Michael Black
 
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"Jim" ) writes:
Bob,

Thanks for the info.

Do you have any experience with this kit?

One question I have is the since the converter has a simple local
oscillator, will the "readout" be accurate and will the frequency be
"stable"??

Thanks

Jim


A crystal controlled converter is a very old scheme to add coverage
to an existing receiver. Since it's crystal controlled, there would
have to be very odd circumstances for it to be unstable.

All you do is add the frequency of the crystal to the frequency
displayed on the receiver. It's easy so long as the crystal in
the converter is a nice even frequency. In the analog days, the calibration
of the dial would likely be more significant than the exact frequency
of the crystal. With digital redout receivers, this is likely somewhat of
an issue, since while the crystal will stay on frequency, in the circuit
it may oscillate at a slightly difference frequency from the marking on
the case. If you're lucky, the converter has a trimmer capacitor for
this sort of adjustment; all you'd have to do is tune in the oscillator
frequency with your receiver and see if it's on frequency. If not, then
you adjsut the trimmer. If there's no trimmer, you still take note of
the crystal frequency in the receiver, and use that knowledge to adjust
your mental readout. If it's 1KHz off from the marked frequency, then you
know you know you will have to add or subtract that amount (depending on the
direction of the offset) when looking at the receiver's readout.

Michael
Bob Monaghan wrote in message
...
see http://home.att.net/~jacksonharbor/lfconv.htm Jackson Harbor Press
kit - $12 for the basic kit (10 to 300 khz to HF) with the crystal
included, parts and circuit board etc. They take paypal etc.

hope this helps bobm
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