Found in American documentation from the 1980s, this circuit operates in the frequency range 0.5 to 20 MHz. The power can be between 5 and 15 V.
This circuit turns on a lamp after the time set on the potentiometer. The circuit is from a Radio...
This signal amplifier for ATV in the 427 to 439 MHz band was found in a magazine 73 for radio...
This amplifier has a few Watt output, using old transistors. The speaker is 45 ohms, but with...