Found in a 1968 Novel Electronics Circuit, this circuit compares two light intensities using common LDRs as sensors. Transistors can be modern PNP equivalents.
We found this TTL circuit with the 7400 in the January 1975 Radio Electronics magazine. The power...
This adjustable direct current source circuit uses a triac operating as a variac. The circuit is...
This radio's transistor is powered with the signal's own energy, producing its amplification....