This audio amplifier circuit was found in Radio Electronics magazine from June 1966. The circuit is a commercial RCA type and is powered by mains power.
Based on an Analog Devices LTC1540, this circuit consumes only 50 uA, serving to monitor the...
The maximum time interval of this circuit depends on C1. Larger values can be used to get closer to...
Linear Technology's LT213 circuit, which suggests this application in 90s documentation, is not...