This is the circuit of a modified Heathkit kit. The circuit was found in a Radio Electronics from December 1965. The author of the circuit included improvements to the original circuit.
This Schmitt optical trigger with LDR was found in old documentation. The relay must be sensitive, or an...
We found this circuit in the January 1997 Electronics Now magazine. The triac determines the...
This transmitter uses a small loudespeaker (FTE) as microphone and can send the signals to...