This signal multiplexer circuit for early low-frequency oscilloscopes was found in the May 1977 issue of Radio Electronics magazine. The circuit requires a symmetrical source.
The figure shows how to control the blinking of a 5 V blinking LED with an LDR. The LED only...
Suggested by Maxim in documentation from the 90s, this circuit has its response curve given next to...
This circuit is from a 1965 General Electric publication. It uses a thermistor to fire a reed...