This optical sensor circuit for a robot was found in the March 1986 issue of Radio Electronics magazine. It controls two motors according to signals from optical sensors or couplers.
With the change of the coil, the circuit can operate at frequencies between 30 MHz and 150 MHz....
The frequency of this Pierce oscillator, found in 1969 documentation, depends on the crystal. The...
This simple circuit can be used to power a simple communication system using ordinary telephones....