This circuit was found I a 1965 Radio Schack documentation. The transistors are from that time, admitting equivalents. The transformer has 500 ohm primary and secondary depending on the speaker.
This circuit was found in the PC documentation from 1996. The maximum current of the motor is...
This circuit is from the time when the 741 was first introduced. It was published in the February 1971...
Only two transistors are used in this preamp for low-sensitive transducers, such as guitar and...