This circuit was found in a 1970 US publication. Transistors are still common and the circuit can be used as a PWM shield or pulse transmission modulator.
This is a factory circuit from an 80's manual. The circuit can be implemented with modern...
This amplifier allows you to recover recorded tapes from a tape player that has the mechanism in...
This circuit is from a magazine 73 for radio amateurs of the 90s. The circuit generates the high...