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 78XX series voltage regulator integrated circuits do not support an input voltage greater than...
This is the complete circuit of a multimeter using a 50 uA instrument with a 2k coil. The circuit...
This circuit came out in a Popular Electronics from December 1995. It is a double T configuration that...