This circuit of a 1964 Electronic Design uses a photodiode from the time. Modern equivalent can be used. The standby current is 1.2 mA.
The purpose of this 1-transistor amplifier is to allow the use of a milliammeter in an application...
This circuit causes one LED to light up if the voltage falls below the value set in R3 and the...
This circuit was found in a 1986 documentation and it may be difficult to obtain some of its...