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 the divisor N being controlled by {HEAD ~ 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 the divisor N being controlled by { HEAD ~ 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 OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD