This circuit was found in Radio Electronics from the 90s. The transducer is a tweeter and the power transistor must have a heatsink.
This analog ammeter circuit was found in documentation from the 1980s. The components admit...
This conventional Hartley oscillator circuit with an audio output transformer was found in a...
This bar or moving point indicator (bargraph) employs the LM3914 and can excite 10 LEDs, of any...