Found in a Popular Electronics from the 9s, this circuit has output for RS-232 interfaces and current input. The power supply must be symmetrical.
The original frequency of the Pierce Oscillator with bipolar transistor is given by the crystal, which...
This circuit was found in an American magazine in 1978. It activates a relay when the speed of a...
An interesting and useful configuration for the control of power loads is shown in the figure. In this...