Continue to Site

Welcome to our site!

Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

  • Welcome to our site! Electro Tech is an online community (with over 170,000 members) who enjoy talking about and building electronic circuits, projects and gadgets. To participate you need to register. Registration is free. Click here to register now.

Police Flash Lights

Status
Not open for further replies.
You could do it fairly easily with a 4017 and a 555.
This thread had a circuit which could work with some fixes to it. It does have errors which can be fixed if the circuit doesn't seem too complex for you. Do you want to use LEDs or light bulbs?
EDIT: The circuit in the thread/post above will work as posted if the power leads for the 4017 are added. I would also remove R4. I don't see why it is necessary.
 
Last edited:
kchriste,

I want LEDs just like it's shown in the video. YouTube - Police Flasher Circuit

I found a design by colin. **broken link removed** Will this design work just like in the video? How many times will each side flash? And how can i modify it to make it look like the one in the video. Thank you.
 
I also noticed in the video that a CMOS CD4001 quad NOR gate chip is used to generate the clock signal and to decode the outputs for the LED's...
 
I also noticed in the video that a CMOS CD4001 quad NOR gate chip is used to generate the clock signal and to decode the outputs for the LED's...
That is another way of doing it. Did you find a schematic for the circuit in the video?
Will this design work just like in the video? How many times will each side flash?
Not exactly like the video. It will flash 3 times each side.
And how can i modify it to make it look like the one in the video. Thank you.
I haven't tested it, but this should work (Flash 2 times a side):
 

Attachments

  • PoliceLights-3.GIF
    PoliceLights-3.GIF
    6.9 KB · Views: 1,597
Last edited:
Here's an idea.

I've never built it or simulated it so I don't know how well it will work.

It uses three oscillators, two higher frequency oscillators which are gated by one lower oscillator.

The idea is to do it with one non-programmable IC. I'm sure there are other ways to do it.
 

Attachments

  • Police LEDs.PNG
    Police LEDs.PNG
    1.9 KB · Views: 829
283-282-38398d1264960368-police-flash-lights-police-leds.png


You need to reverse and tie the LEDs to Vdd. Otherwise they will be ON when they aren't flashing.
Also, the first flash (Every time it switches sides) will be longer than subsequent ones, due to the cap being nearly fully charged when the section is idle. Maybe the OP doesn't mind that. Creative solution though.
 
Last edited:
Yes they're NAND gates so their outputs will be high when disabled.

You're also right about the capacitor charging problem.

I suppose I should think more before posting circuits.

It might also be possible to do a similar thing with a hex inverter: two gates could be used to make an astable with complementary outputs which would be used to control to control two other oscillators, again I haven't thought it through properly so there could be other flaws I haven't spotted.:D
 
thanks

Thank you guys for all the help, i bought components over the weekend and I will be testing your circuits... I also found another circuit on the internet, so i'm going to share it in case somebody else ever needs a police light circuit...

296-3lampi2.gif
 
This is pretty neat, but I was always wondering how to do the same with strobe lights.
I know it would require a big storage of power for multiple short pulse flashes in each circuit, and also a means of triggering, but (utilizing the circuitry above) how 'bout controlling strobes??
 
This is pretty neat, but I was always wondering how to do the same with strobe lights.
I know it would require a big storage of power for multiple short pulse flashes in each circuit, and also a means of triggering, but (utilizing the circuitry above) how 'bout controlling strobes??

hi, from the description i read you can control the strobes through the 220K variable resistors, i saw a video of the circuit in action, it's pretty neat.
 
I am looking for a police flash strobe light circuit. I bought my son a power wheels car for his birthday and would like to install the circuit on the car... (9-12Volts)
Here's what i'm looking for... YouTube - Police Flasher Circuit

thank you.
i did this a long time ago when someone wanted to fit it into a toy police car... though he wanted a red-red-blue-blue cycle.
 

Attachments

  • flasher.PDF
    13.3 KB · Views: 625
Edgari, and everyone else, what I mean is, where into the strobe circuit (that circuit would be of benefit as well) would I lead the signals in to cause the strobes to fire (I believe I would only need the diagram for the step-up of the tubes w/o the timer as would not be the case with a "normal" strobe light circuit). Clarification...The circuit just for firing the strobe, and where to send the 4093 outputs into it !
 
Edgari, and everyone else, what I mean is, where into the strobe circuit (that circuit would be of benefit as well) would I lead the signals in to cause the strobes to fire (I believe I would only need the diagram for the step-up of the tubes w/o the timer as would not be the case with a "normal" strobe light circuit). Clarification...The circuit just for firing the strobe, and where to send the 4093 outputs into it !

you do know that strobe tubes are notoriously short lived, dont you? they have a 1-2k flash limit. real ones use power strobe rated LEDs these days for just that reason.

now what those use i am not quiet sure, though it would be simpler to use a simple capacitor/current limit resistor to flash an LED.

dan
 
I was unaware of a "strobe LED". Just a really high MCD, maybe multiple LEDs in the same area?
Those old Rad** **ack strobe kits fired more than 1-2K times... So tell me then, where can I get some super extreme bright LEDs that are white, w/o breaking the bank? I'm not talking 5-7K MCD, how about something in the tens of thousands millacandela???
 
I was unaware of a "strobe LED". Just a really high MCD, maybe multiple LEDs in the same area?
Those old Rad** **ack strobe kits fired more than 1-2K times... So tell me then, where can I get some super extreme bright LEDs that are white, w/o breaking the bank? I'm not talking 5-7K MCD, how about something in the tens of thousands millacandela???

well it seems lumileds discontinued it since the rebels outperformed it anyhow. you have a misunderstanding as to how to spec things... mCD is an intensity measurement that only applies to a target surface at a particular viewing angle at a particular distance... Lumens, Lm, is a measure of actual light output.

a typical crap 5K mCD LED has a viewing angle of, we'll be generous, say 20 degrees, for a Lm output of around 0.5Lm. Since a Rebel is capable of putting out over 150Lm it, by your comparison, puts out 1500K mCd when focused to a 20 degree beam.

Dan
 
The circuit is larger in the post below:

**broken link removed****broken link removed**
 

Attachments

  • PoliceLights-3.gif
    PoliceLights-3.gif
    4.8 KB · Views: 1,593
Last edited:
Here a simple circuit that will flash 3 high bright LEDs 3 times and alternate with red and blue LEDs
 
Ubergeek63, what is a "Rebel"? Even if I point the LEDs in varied angles, I would get a wide coverage. So I'll rephrase my inquiry, where can I get some REALLY REALLY bright white LEDs, the brighter the better, the more lumens the better, the larger the better, the wider angle the better? I'm seeking to modify the security cart at my work (inside the taillenses), with what the lawman has on his undercovers. Is "SuperLEDs" (or whatever the heck their name is) going to be my best bet?
 
Ubergeek63, what is a "Rebel"? Even if I point the LEDs in varied angles, I would get a wide coverage. So I'll rephrase my inquiry, where can I get some REALLY REALLY bright white LEDs, the brighter the better, the more lumens the better, the larger the better, the wider angle the better? I'm seeking to modify the security cart at my work (inside the taillenses), with what the lawman has on his undercovers. Is "SuperLEDs" (or whatever the heck their name is) going to be my best bet?

Rebel is a trade name for luxeon's latest line: LUXEON Rebel Color LEDs | Compact Color Power LEDs

you do not want whites if you can get clear lenses... you throw your light away requiring more power and more money. **broken link removed** is a star mounted emitter... 80 Lm at 350mA and 165Lm at 700mA ...

i would venture a guess that since you are looking at 300x Lm and 10x area (3x the viewing angle) you are talking about 30x the brightness of a 5k mCd 20deg T1 3/4, or about 150K mCd ... at what point would you be comfortable just saying 150Cd? ...

now the problem with whites, is that you are filtering out 80% of your light in color filters for the sake of your comfort zone. efficiency would dictate that you drop the filters and use the colors you want to save money and power.

dan
 
Status
Not open for further replies.

Latest threads

New Articles From Microcontroller Tips

Back
Top