This transmitter emits a modulated signal at a frequency given by the first transistor in the phase shift oscillator. The circuit is from an Australian publication from 1991.
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...