This circuit is from old American documentation, using a regulator integrated circuit that is uncommon today. The diodes can be 1N4002 and the transformer has a 500mA secondary.
The circuit shown in figure 1 is suggested by Maxim (www.maxim-ic.com) and makes use of the...
This high impedance circuit uses a 12 V lamp to test voltages in a car. We found it in a Popular...
This circuit was found in an Electronic Design. It makes use of a relaxation oscillator to trigger...