[time-nuts] frequency reference for portable operation
rexa at sonic.net
Mon Mar 11 03:09:48 EDT 2013
On 3/10/2013 6:10 PM, Hal Murray wrote:
> rexa at sonic.net said:
>> or if you have a beacon in range that you can find to establish your
> What do you do after you determine the offset?
> Do you tweak it out with a trimmer (R or C)? Or tell the software? Or do
> the corrections with pencil and paper?
The typical rig would use a 2 meter radio as the low end transceiver.
The microwave radio usually would be set up so that 10368 MHz would tune
down to 144 MHz on the "IF" radio. So if you tune a beacon that you
expect to be at 10368.300 and find it at 144.301, you now know your
radio tunes 1 kHz high so you transmit and listen 1 kHz high vs the
dial. Or you could go, "1 KHz isn't a lot", so just ignore it and assume
the other more experienced operators will figure it out. After a couple
contacts I usually figure out that I should listen for another
particular station with a certain offset. More complicated, a certain
station may have an offset of xxx Hz between Tx and Rx. I hate that
because my IF radio is a pain to tune RIT (receive vs Tx offset) so it
is hard for me to correct and we wind up chasing each other. up or down
the band between tx/rx iterations.
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