This amplifier with two FETs in direct coupling (cascode) was found in a 90s Popular Electronics. The MOSFET can be of almost any type like the MPF102.
To control relays safely with double insulation through the parallel port, we suggest the circuit in...
This '80s circuit drives an infrared LED, producing a modulated signal. Modern higher power LEDs...
This small receiver for the medium wave range was found in Radio Electronics magazine from July...