I need a 12v pulse when the power switch on and when the power is switched off,
I have looked and made the monostable kit but that only works when your have a switch/reset. the switch cant be on all the time. (power on perm)
i have looked at a timer kit which works one way, when you power up there is a pulse, but i need the same pulse when the main power stops.
i have looked at loads of the 555 kits, but not to sure if i will need 2 kits,
1 kit when the power is on then another kit when the power is off, if that is the case then i can use a 556 chip, but i am stuck when the power is off for the 2 pulse trick.