We found this active crossover in a Radio Electronics magazine from June 1961. Note the different adjustment ranges. The signal must be applied to the amplifier input.
In a modern version this circuit can use an LED in series with a resistor in place of the lamp. The...
This bistable circuit with SCR for direct current was found in the Radio Electronics magazine of...
The configuration shown in the figure uses two NPN transistors activating the load when the input...