We found this circuit in documentation from National Semiconductor. For the medium wave range the coil consists of 50 + 50 turns of wire 28 in a ferrite rod.
The sensor of this circuit is an NTC and the indication is made on a common analog indicator, and...
This 1.2 to 32 V x 3 A regulator was found in an 80's EDN. The power components must be equipped...
This circuit turns off after a time that depends on C1. The circuit is from an Electronics Now...