This circuit can be used to generate percussion sounds such as bell, triangle, etc. The circuit must be powered by symmetrical source and the triggering is by external pulse.
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...