# Commercial strobe light speed **URL:** \ **Category:** Factual Questions\ **Created:** [November 1, 2014, 3:34am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197 "2014-11-01T03:34:31Z")\ **Posts on this page:** 11\ **Page:** 1
**Author:** ![Mdcastle](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mdcastle](https://boards.straightdope.com/u/Mdcastle)\ **Post date:** [November 1, 2014, 3:34am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/1 "2014-11-01T03:34:31Z")
Can an ordinary “disco party” consumer strobe lights that have a variable speed operate up to 15 Hz? ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [November 1, 2014, 4:05am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/2 "2014-11-01T04:05:57Z")
No, most are only promising up to 10Hz. ---
**Author:** ![Mdcastle](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mdcastle](https://boards.straightdope.com/u/Mdcastle)\ **Post date:** [November 1, 2014, 1:45pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/3 "2014-11-01T13:45:37Z")
Would it be simple to custom build a circuit to do this? Say a 555 driving a power mosfet driving an array of 12 volt LEDs? ---
**Author:** ![Learjeff](https://avatars.discourse-cdn.com/v4/letter/l/94ad74/32.png) [@Learjeff](https://boards.straightdope.com/u/Learjeff)\ **Post date:** [November 1, 2014, 2:37pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/4 "2014-11-01T14:37:23Z")
> [@Mdcastle](#): > > Would it be simple to custom build a circuit to do this? Say a 555 driving a power mosfet driving an array of 12 volt LEDs? I think you’re barking up the right tree. The trickiest part is the power relay (power mosfet), which converts the control signal into a power switch for the (relatively) high power LEDs (as I’m sure you understand). Unfortunately I don’t know how to apply them. However, rather than using a 555 timer, I’d consider using something like an Arduino (hobbyist microcontroller), which would make it very easy to configure and/or control in different ways (like, over 802.11 using a simple mobile app). But for a simple constant-rate or switch-controllable timer, a 555 is the time-honored solution. You could always start with a 555 on a breadboard and replace it with an Arduino if you wanted more control options later. Two nice things about Arduinos is that there’s a huge body of available software modules for them, and they come in lots of flavors with different peripherals (including 802.11 wifi, IIRC). Who knows, maybe there’s even one with built-in power relays. I bet there are also power relay IC’s, which would be MOSFETs with all “care & feeding” circuitry inside, expecting only power, ground, and TTL level control signal inputs, which would simplify things considerably. Hopefully someone who knows anything about this stuff can mention a part name or good google search phrase. Of course, you’ll also need a power supply, with control signal voltages and whatever the LEDs require. I’m just guessing, but I bet you’d want to control the LED power circuits directly, rather than switching the AC feed to an integrated lighting device. But I could be all wet there! My guess is it would depend on the properties of the LED device’s power supply; I doubt that most are designed expecting the power feed to duty-cycle. ---
**Author:** ![Mdcastle](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mdcastle](https://boards.straightdope.com/u/Mdcastle)\ **Post date:** [November 1, 2014, 3:33pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/5 "2014-11-01T15:33:41Z")
I do indeed want to control the DC to the LEDs. I was thinking about either just a commercial 12 volt “wall wart” or just a 23A battery, as to not try to reinvent the wheel. ---
**Author:** ![jz78817](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jz78817/32/1028_2.png) [@jz78817](https://boards.straightdope.com/u/jz78817)\ **Post date:** [November 1, 2014, 4:33pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/6 "2014-11-01T16:33:13Z")
if you look up “LED Stroboscope” you’ll find some handheld units that can go way above 15 Hz. we have a Hoto ESL-200 we use at work to watch how speaker cones act at various frequencies. ---
**Author:** ![Mdcastle](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mdcastle](https://boards.straightdope.com/u/Mdcastle)\ **Post date:** [November 18, 2014, 12:27am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/7 "2014-11-18T00:27:25Z")
I passed on the idea of using an Arduino because I know absolutely nothing about computer programming. How do I make sure I’m not exceeding the 600mW power rating of the 555? I know a string of a some 60ma LEDs and the resistor consume 500-600 mW, is this the number you use that you can’t go over? ---
**Author:** ![Melbourne](https://avatars.discourse-cdn.com/v4/letter/m/b5e925/32.png) [@Melbourne](https://boards.straightdope.com/u/Melbourne)\ **Post date:** [November 18, 2014, 4:39am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/8 "2014-11-18T04:39:15Z")
> [@Mdcastle](#): > > Can an ordinary “disco party” consumer strobe lights that have a variable speed operate up to 15 Hz? No. A common explanation is that disco lights are more likely to cause epileptic fits above 10, but I’ve seen no actual data to support that. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [November 18, 2014, 4:52am UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/9 "2014-11-18T04:52:56Z")
> [@Mdcastle](#): > > I passed on the idea of using an Arduino because I know absolutely nothing about computer programming. How do I make sure I’m not exceeding the 600mW power rating of the 555? I know a string of a some 60ma LEDs and the resistor consume 500-600 mW, is this the number you use that you can’t go over? Don’t try to drive the LEDs directly off of the 555. Get a logic-level N-Channel FET, and have the 555 drive that. That will give you essentially unlimited power (I’ve driven FETs that can handle 185A of current). ---
**Author:** ![Mdcastle](https://avatars.discourse-cdn.com/v4/letter/m/958977/32.png) [@Mdcastle](https://boards.straightdope.com/u/Mdcastle)\ **Post date:** [December 14, 2014, 3:42pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/10 "2014-12-14T15:42:39Z")
I got the basic circuit working (555 driving a 4024 driving a 2N2222) with a couple of standard LEDs. I want to expand it now with a high powered “star” emitter. To not invent the wheel, there are “buck pucks” designed to drive a high powered LED with constant current. Some of them have an input for PWM dimming. Can I connect the output of a ripple counter directly to that, or conceptually do I want to switch the whole driver with a high powered FET or Darlington? ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [December 14, 2014, 3:46pm UTC](https://boards.straightdope.com/t/commercial-strobe-light-speed/703197/11 "2014-12-14T15:46:25Z")
> [@Mdcastle](#): > > I got the basic circuit working (555 driving a 4024 driving a 2N2222) with a couple of standard LEDs. I want to expand it now with a high powered “star” emitter. To not invent the wheel, there are “buck pucks” designed to drive a high powered LED with constant current. Some of them have an input for PWM dimming. Can I connect the output of a ripple counter directly to that, or conceptually do I want to switch the whole driver with a high powered FET or Darlington? The PWM input should do exactly what you want.