This shunt voltage regulator was found in an Electronic Design from the 90's. The power transistor must be in accordance with the load current and must be equipped with a heat sink.
Equivalent transistors, such as the BC548, can be used in this circuit that we find in...
Found in a 90s documentation, this circuit makes use of D1, a switching diode that is uncommon today....
This is the suggested transmitter circuit for the CB16880E. The emitting LED must be a...