I agree, very good post from Jason. BUT -- I am not sure this is likely to be exactly correct. I would believe that they may be dealing with the ground mineralization with one or more frequencies, in multi-freq. HOWEVER, if you are running, say, 5kHz single freq., Park mode, while coin hunting, and then you switch to "multi-frequency" while in Park mode... the designer has already said that the frequencies used in multi-freq. Park mode will be "appropriate" for that mode, so let's say it's 5, 10, and 15 kHz. If the 10 and 15 kHz channels, lets say, are just for ground compensation, while 5 kHz is the "detecting channel," then WHY WOULD ANYONE EVER choose 5 kHz single freq., when you could choose multi-freq, still hunt at 5 kHz, but have the ground being compensated for in a superior way using other frequencies? I can't see why you'd ever WANT the single freq. 5 kHz, if it is set up the way Jason is suggesting. You'd ALWAYS want the ground compensated for in a more "robust" way using multi-frequencies, no? I HAVE TO BELIEVE, at this point, that the multi-freq. option uses algorithmic comparisons of at least two different frequencies (that are being used as "detecting" frequencies), and comparing the signal of those two to give a better, more accurate target ID, no?
Again just speculating, but I wonder...
Steve