With an 18 V input, this regulator was found in Philips documentation from the 60's. The transistors are from that time. The power transistor must have a heatsink.
This circuit was published in a 2000 documentation. The circuit activates the warning lights in...
This test consists of a simple Hartley oscillator using a transformer of the type found on older...
12 V motors and current up to a few amps can be controlled by this circuit that we found in a 1991...