This circuit was originally recommended to give the call signal on intercoms. However, it can be used with other applications. The circuit is from 1978 documentation. The transistor may be the BC548.
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...