This circuit is from an old Mullard (Philips) manual with applications using the 555. Choosing appropriately the resistors and the timing capacitors, the ranges obtained can exceed days.
This circuit drives a buzzer or electric buzzer but can be used to trigger a relay or other load....
Found in Popular Electronics from the 90s, this circuit can be used for high voltage applications and...
August 2016 - The new Schottky diodes from Vishay's ESMP series for surface mounting can now be...