The reference signal is preferably provided by a sine/cosine generator from pulses provided by a divide by N counter occurring at {TAIL ~ the multiplex frequency}, with {HEAD ~ the divisor} N being controlled by the tone switching logic circuit 
The reference signal is preferably provided by a sine / cosine generator from pulses provided by a divide by N counter occurring at { TAIL ~ the multiplex frequency } , with { HEAD ~ the divisor } N being controlled by the tone switching logic circuit
OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH