Flashing led question

[POPEYE]

Dont know if anyone can help, how can i get flashing leds to all flash at the same time, (without complicated circuitry if poss) i want to hook up hazards to a model truck and three trailers (eventually) so not sure yet how many there will be, any help apprecieated

[Apache]

Dont know if anyone can help, how can i get flashing leds to all flash at the same time, (without complicated circuitry if poss) i want to hook up hazards to a model truck and three trailers (eventually) so not sure yet how many there will be, any help apprecieated

You can't really, as the flasher chip is internal. A simple oscillator doesn't take much space, or get yourself a cheap LED bike light and butcher it.

[POPEYE]

Righto Andy thanks, i could prob locate any "flash controller" outside the display case i intend useing so i guess the size of it wont matter too much, so rather than buying flashing leds do you reccon i'd be better buying ordinary leds and makeing them flash from a controller? i could pop into maplins and see if they do a kits for this purpose.

[Apache]

This looks easy enough Ian. I'd knock one up myself but my workshop is still flat packed in the drive, and all my electronickery is still in boxes down the back of the garage!

[slobodan]

I think your head needs changing.

[POPEYE]

Cheer's andy, please dont worry about making one, i can do it as long as i know what componants are what, i'm probably going to need about 28 leds to all flash at once, thats 4 for the tractor, and 8 per trailer (4 on the front and 4 on the back of each trailer X3)
the power source will be 12v, i did see a drawing very much like yours there while googleing but not sure if that drives just one led or several, (guess i'd need to know the total forward voltage of all leds) if it only drives a few i could do more than one controll i suppose, fit em all in a maplins box with just one on/off switch, anyway if i can catch the older guy at maplins i can ask him, no good asking the young ones as i'd prob just get a blank stare from some spotty faced fecker

[POPEYE]

I think your head needs changing.

you got a younger one knocking about? i could do with a new head (and body) (and hampton wick!! make it a tad bigger this time)

[Apache]

Where you have the output of the 555 driving the LED, just use that output to drive the base of a medium power transistor, and put the LEDs in parallel on the collector (ground the emitter). Say you have 10 LEDs and want to run them at 5 - 10ma each (which should be ample for what you are doing) you just scale the resistor to give 50 - 100ma.

If you google 'transistor switch' you'll find clearer explanations.

The old guy at Maplin will explain - and you'll have the satisfaction of doing it yourself - good luck!

[POPEYE]

Where you have the output of the 555 driving the LED, just use that output to drive the base of a medium power transistor, and put the LEDs in parallel on the collector (ground the emitter). Say you have 10 LEDs and want to run them at 5 - 10ma each (which should be ample for what you are doing) you just scale the resistor to give 50 - 100ma.

If you google 'transistor switch' you'll find clearer explanations.

The old guy at Maplin will explain - and you'll have the satisfaction of doing it yourself - good luck!

Thanks mate, much apprecieated