Re: Controlling the HF-150
On page 7 of the HF-150 Technical Manual it states that the HET frequency (ie the interpolation frequency) can be controlled in 128 steps across its 1 kHz range, each step being nominally 7.8 Hz. My comment is that this will be set in the firmware, and is independent of the encoder pulses per revolution. The encoder ppr sets the tuning rate, not the tuning resolution.
Looking at SiriusHardware's numbers, and following on from my earlier edited post it seems that:
the decimal number = INT(last three digits * 0.256) with a range of 0 to 255
and:
the control number = INT(decimal number / 2), with a range of 0 to 127
If this is correct, the sent number uses 8 binary digits, but only the 7 most significant digits are used as the HET control.
Please, if Jez were up to doing more tests, these numbers might help:
0.039 kHz, decimal number = 9.984, sent number = 0000/1001
0.961 kHz, decimal number = 246.016, sent number = 1111/0110
Thanks and 73
John KC0G / M0KCY
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