This amplifier was found in a 1970s documentation. Darlington transistors can be replaced for modern equivalents of at least 80 V x 2 A, equipped with good heat sinks.
This circuit multiplies the input voltage by 3 and can work with up to 12 V input. The current is a few...
This circuit was obtained in a Hands-On Electronics from the 90's. The circuit turns on one LED at...
This telegraph monitor was found in an American documentation for radio amateurs from the 1970s. The...