This circuit came out in a publication called Electronics Handbook of 1993. The circuit shows how to implement a good common telephone line protector.
Found in a 1969’s documentation, this circuit can supply currents from 100 to 120 mA at loads of...
We found this receiver in old documentation. The transistor is made of germanium and the...
We found this project in a 1982 publication. What we have here is an audio signal relay trigger, which...