Frequency Measurement with the FT-920


Find Zero Beat:

Set mode to CW (USB)

Tune to WWV 10.00000 MHz or any other reference station you can copy.

Set the dial resolution to Fine. You should see a row of tick marks above the main frequency readout. These are the 1 Hz marks.

Make sure SPOT-TX in Menu 5 is set to OFF

Rotate Pitch control fully ccw. This gives the least amount of error if the tone is off frequency.

Push the Spot button and adjust the sidetone level to about the same audio level as WWV. 

Very slowly tune back and forth until you find the Zero Beat.

If the dial still reads exactly 10.00000 and no tick marks (except for the one in the center) your in luck as your radio is calibrated. If not then at this point you can either take the covers off the radio and adjust the master oscillator or generate a correction factor in the next steps.


Generate correction factor:

Make a note of the exact frequency in Hz. of the zero beat, by counting the tick marks and adding to the main dial reading. Remember the center tick mark is zero. A tick mark on each side of zero is 1Hz.

Calculate the difference between the total dial reading (including ticks) and the know reference frequency (in my case 10,000,000 Hz).

If the dial reading is higher than the reference then the calculated correction factor is negative. If the dial reading is below the reference then the calculated correction factor is positive.

This correction factor is only good at or very near the current reference frequency. To use the correction factor, say for the 80 meter FMT run, first divide the correction factor by the reference frequency in MHz. In my case 10MHz. Then multiply by the 80 meter frequency of 3.55MHz. This is the correction factor to use on 80 meters.

During the FMT on 80 meters do everything in steps above to find Zero Beat except find the zero beat of the FMT station. Use the calculated correction to add or subtract from you dial reading after you find the zero beat.




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