Found in a Popular Electronics from the 90s, this circuit can act as a transmitter for an audio link. The output transistor admits a higher power equivalent, depending on the LED.
This simple charger was found in a 1980s documentation. The transistor may be the TIP42 with a...
This circuit is used to run light bulbs around street signs. Incandescent lamps up to 40 W are...
This high frequency or RF amplifier was found in a 90s Popular Electronics. The circuit can be...