Suggested by General Electric in a 1968 documentation this integrated amplifier uses a component of the era, the PA237. The circuit runs on 24 V and excites a 16-ohm speaker.
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...