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Old March 15th 05, 04:11 AM
RST Engineering
 
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Firstly, 108 to 118 MHz is the international civil
aviation radionavigation band. It's not all that
interesting to listen to unless a local tower is
also repeating voice comms over a VOR or Localizer
radionav transmitter nearby on the ground. The
civil aviation voice band is 118 to 137 MHz.


Firstly, the tower does NOT repeat voice comms over a VOR. The local Flight
Service Station MIGHT, but in the days of crystal controlled navcoms, the
amount of voice traffic on a VOR is next to nothing.

Secondly, the tower/FSS will never in HELL repeat something on a localizer
frequency.

You are correct; the civilian aviation voice band is 118.000 to 136.975 MHz.



Jameco sells the MC145151 PLL IC (On Semiconductor
the Motorola spin-off still makes them) which, with
a prescaler, can make a good, stable LO that is
channelized at 50 KHz increments for precise tuning.
MC145151 is parallel-load for division, no extra
IC needed to get the right division ratio as in
some serial-input PLL or DDS chips.


The 145151 is OK if you don't mind spurs every 25 kHz. from dc to daylight.
The 145152 is a much better dual-modulo prescaler that gets rid of a lot of
trash and garbage from single modulo prescaling that you probably don't
want.

Jim