Found in the 1969 neon lamp documentation, using neon lamps this circuit provides 18 V regulated with 0 to 4 mA current. The lamps are types of the time.
This interesting FET-tester circuit was obtained from an old American documentation. The bipolar...
Found in a 90s Electronic Design, this suggestion to have a higher voltage in a fixed regulator...
This circuit was found in the July 1994 issue of Electronics Now magazine. The relay can be rated...