Police Flasher

[GlleONeill]

Can you give me the R3 caracteristic?

[MrTech302]

Where can i get a parts list and schematic for this circuit?

[deeaks100]

if you use a 10k pot in place of resistor 2, you can vary the rate of flashes.

[opiumrx]

whats the woltage needed for the high current one?

[alt5productions]

I built this on a breadboard and and moving to a PDB soon. I drew up a schematic in Eagle that you can download from edcarlson{dot}com/files/led_st­robe.sch. I felt that the flash rate was too high with a 1uF cap, so I swapped it out for a 3.3uF which gives a slightly slower flash rate.

[ananababa123]

i built it and both leds flashes at the same time! what can be the failure?

[R5H4D0W]

@ananababa123 if your using darlington pairs Mosfets, or other large transistors that are TO-220 packaged, the metal part where heatsinks are screwed to might be shorted to each other [I.E using the same heatsink] For mine I use TIP122s, the heatsink part is the collector that connects to the LEDs, using the same heatsink will result in both flashing at the same rate. Hope this helps :)

[13royalknight]

can u sent me the shematics?

plzz

[asdgz]

Thanks for the shematics! ;-)

[EstonskiTV]

i changed the 1uF cap to 3,3uF.. looks nicer :) thanks altho!!!

[STFUProductions]

anyone had any problems with this? i built it and hooked it up to 12volts but cant get it to work

[weeardguy]

@ STFUProductions: well, the circuit looks good: exactly the same how I built it 5 years ago.

The only thing I miss in the schematic: a decoupling capacitor for the 4017, and an electrolytic cap for the 555.

Check if the clock (the 555 circuit) is working. disconnect the 4017 for a while, and test with a led (AND RESISTOR) on pin 3 from the 555 if there is an actual clcok-train.

For a schematic as an image, click my profile, where you will find a link to my website: you can also send a PM.

[rdko7]

Does anyone have a components list for this?