We found these circuits in a 90s Radio Electronics. In them, we have the way to turn a load on and off using pressure switches. The circuit can be used with other types of direct current load.
The TDA2613 is the mono version of the TDA1521A and has pinouts compatible with an integrated...
This circuit from an old 1978 publication uses germanium transistors but can be implemented with...
This project shows how to use an SCR in a starter circuit for a common fluorescent lamp. The SCR...