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 is from a 1976 publication and can be assembled with more modern operational...
This CMOS Flasher was found in a Popular Electronics from 1978. It can still be easily assembled, as all...
The integrated circuit used is a double 741 from SGS. The transformer is the critical component of the...