The power transistor of this circuit can also be the TIP42 mounted on a good heat sink. The circuit is from old European documentation and the integrated circuit used is not very common today.
This circuit was obtained from an old American documentation having a limited adjustment range....
This 555 timed touch switch was found in a 90s Hands-On Electronics. It triggers a buzzer, but a...
The transistors of this old circuit from the 60s can be the BC548, in a current version. The...