The operational amplifier of this circuit can be the 741. The circuit has very low consumption and can be powered by two 9-B batteries. Low voltage amplifiers can be used.
This circuit uses an LM339 and was found in the July 1995 Electronics Now magazine. The LED lights...
We found this circuit in an old Mullard (Philips) documentation on the 555 and 556 integrated circuit...
This circuit was obtained from an 80's documentation from General Electric. The circuit uses an...