The transistor in this project found in the July 1994 issue of Electronics Now magazine can be any general-purpose type. The circuit is powered by the relay voltage up to 12 V.
We found this circuit in an old QST magazine. The circuit is powered according to the thermostatic relay...
This circuit was found in a 90s Popular Electronics. The components are from the era. R3 must be...
Found in a 1968 EEE, this circuit accepts frequencies from 1 to 1000 Hz and control voltages from 0.1 to...