This old 1 W audio amplifier transistor circuit is from a 1967 Japanese magazine. The transistors are germanium of the time and the type transformers found in similar equipment of the time.
This amplifier can work with voltages between 12 and 22 V. This means that we can use it in the...
When pressing S1, S2 or S3 this circuit generates different tones for a tone-modulated...
The configuration shown in the figure uses two NPN transistors activating the load when the input...