Found in a 90s documentation, this circuit makes use of D1, a switching diode that is uncommon today. D3 is an LED. The circuit monitors 12 V batteries.
We found the circuit for this commercial radio in Japanese documentation from the 1960s. The...
We found this traditional configuration in an Italian 1960 documentation. The transistor can be...
We found this circuit in recent English documentation. It can provide an output current between 9 and...