Phase-lock-loop operating ranges measurement

A measurement method is presented that quickly displays the operating ranges of phase-lock loops (PLLs) and acquisition aids under various input conditions such as noise and interference. The PLL measurement set-up is based on the use of normally available spectrum analyser/tracking generator equipment rather than on the common display of the control voltage of the oscillator. It is shown that in case of a narrow-band PLL the spectrum-analyser display can be more easily interpreted than the control-voltage display.