This circuit was found in a 73 magazine for radio amateurs of the 90s. The circuit uses two types of indicators, the diodes are for general use. The power supply is 5 V.
Taking advantage of the high input impedance of the operational amplifier 741 and its high gain we...
In the figure we have the basic configuration of a regulator for 12 V x 1 A suggested by Motorola in...
This circuit can be used to test crystals from 1 to 20 MHz and also has an output to measure their...