Found in an Electronic Design from the 90s, this circuit measures the phase difference between two signals using an electronic multimeter. The circuit makes use of components of the time.
Found in a 1968 EEE, this circuit accepts frequencies from 1 to 1000 Hz and control voltages from 0.1 to...
This circuit has appeared several times on this site in different applications. This is from 1997...
This setting appears other times in this section from other sources. This is from an 80's American...