This circuit is from Delco Radio found in a 1968’s documentation. The transistors are of the time and are not given information about the driver transformer. Note the high supply voltage.
This basic configuration of voltage regulator using operational amplifier and zener was found in a...
This 75 W power supply was found in American documentation from the 1980s. Transistors can be...
This circuit was found in a 1987 magazine. It measures the pulse rate produced by a cardiac...