This circuit was found in an 80's Electronic Engineering. The circuit uses operatives of the time that are not common today. The power supply must be symmetrical.
This circuit is from an August 1984 Radio Electronics magazine. It monitors the state of a RAM...
In the figure we have the way to obtain an adjustable constant current source of 2 mA. The...
Found in a Maxim publication from the 90s, this circuit generates signals from 10 to 25 kHz with a...