Found in Radio Electronics from the 90s, this siren finds many variations on this site. The transistor must be equipped with a heat radiator.
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...