This is a common oscillator configuration that generates rectangular signals in phase opposition. This circuit is from October 1986 Radio Electronics.
Two transistors connected in direct engagement, so that the first emitter is connected to the base of...
This amplifier with very high input impedance was suggested by Texas Instruments in a manual of...
The coil of this receiver determines the range. It can have 2 to 10 turns of wire 20 to 24 in the...