Found in a 1968 EEE, this circuit accepts frequencies from 1 to 1000 Hz and control voltages from 0.1 to 15 V. The operational amplifier is from the era and can be replaced by modern equivalents.
This circuit with SCR is from a Radio Electronics magazine from September 1965. It is a commercial...
This circuit was found in the July 1986 issue of Radio Electronics magazine. The circuit has a...
This circuit was found in a QST from the 1990s. The circuit expands the scale of a 10V instrument to...