We found this circuit in a Radio Electronics issue from July 1969. The lamp remains on until C1 opens. The time is given by capacitor C1.
The diagram shows an AND gate implemented with an LM3900 transconductance operational. The circuit is...
The load of this circuit depends on the triac and the integrated circuit used is uncommon today. The...
The described electrifier is low cost and easy to assemble. The voltage transformer raises 12 V to...