George, the Pegasus and most other tranceivers do not have a high
stability option, so they will change frequency when they change
temperature. The Pegasus has a software frequency offset that can
be set. After the Pegasus is at opreating temperature I check the
frequency and set the offset. For digital modes or weak signals
it is usefull to have the correct frequency.
This is the frequency accuracy for the Pegasus without the offset
adjustment:
FREQUENCY ACCURACY: +/-90 Hz at 25 degrees C at 30 MHz for 1 yr
That is +/-3ppm.
Regards, Jim FitzSimons W7ANF
George T. Baker wrote:
>
> Hi, Jim
>
> I use exactly the same procedure with my Kachina and consistently measure
> calibration errors in the order of two Hz or less. Amazing that radios in
> these price classes could be so accurate. My Kachina has the High
> Stability Crystal Oscillator option (crystal oscillator oven, etc.).
> Jim FitzSimons wrote:
> > The fastest way to get
> > a frequency measurement of 0.1 ppm at 2.5, 5, 10, 15, and 20 MHz
> > WWV or WWVH is to use the sound card. Tune 1000 Hz high in LSB
> > or 1000 Hz low in USB and look at the frequency with digipan or some
> > other sound card FFT program. Select AFC so the program locks on the
> > carrier. The frequency readout is good to 1Hz. I checked that with a
> > frequency counter.
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