This HeNe laser power supply was found in the March 1989 issue of Radio Electronics magazine. This power supply generated a few thousand volts for gas ignition.
This circuit was found in a 1966 General Electric documentation. The circuit makes use of PUTs...
This circuit is from a documentation from the 50's. The transistors are made of germanium. The...
This circuit allows you to read capacitances on a common analog instrument. It is part of an...