I wish this blog would be updated with more recent discoveries. There are lots of innovative ideas here.

Something to add to this method is you could use the output command to simply use modulated sweeps as well, though I'm not 100% sure this is required given the math the F165 uses to combine frequencies, but just in case here it is.

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program c #Sets the primary channel to C
backfreq b 6.698 50 #Modulation frequency
vbackfreq a 1 0 50 #Copies the primary frequency as a carrier
output 110 110 #Stops the primary frequency from being transmitted so just the carrier and the modulator are used.
xxx #Organism frequency. You can now use sweeps etc which weren't possible using the existing method.
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