Flasher circuit

[Deleted member 3553]

Have a 2 LED unit (rated 9V) operates OK on 6, 9, 12V dc power pack or battery...will not operate from rail power or directly from controller any position....1 LED on other flashing without any control..........explanation appreciated...Thanks Mal R.

 

[nicebutdim]

What controller are you using? Timers usually require a nice smooth supply to operate correctly. If the controller is Pulse Width Modulation (PWM) then it will not work as the supply is effectively a mass of pulses and will 'confuse' the flasher circuit. You could try placing a large capacitor across the supply as close as possible to the flasher circuit and see if that works. If you're going to reverse the supply to the circuit don't forget to use a bidirectional capacitor.

 

[Deleted member 3553]

Thank you NBD............that's all the answer I need.....Controller is PWM one i made up from John Rumming's circuit....The unit is on end of line Buffer but steady lights look OK .....I can run dc from another source if need be..........Regards Mal R.