This low power circuit was obtained from an American 80's documentation. The circuit indicates the voltage of a battery being trimmed by the trigger point. The transistors can be the BC549.
June 2017 - Mouser Electronics announced the availability of the new Texas evaluation module for...
This circuit from Popular Electronics powers a small speaker. The transistor can be of general use...
This circuit using components that are still common in our market was found in a 1987...