This circuit is from the 70s. The integrated circuit used is not common today and the supply is made with a voltage found in televisions of the time, where it was used.
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...