The Flashing Light Prize - Page 1
Forum section: electronics / general

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: December 09, 2016, 12:14:29 am
content: Inspired by the 555 timer contest...Find an unusual, interesting or crazy way to flash an incandescent lamp?Then enter the Flashing Light Prize :http://www.flashinglightprize.com/Quote

author: @rt
author_rank: Super Contributor
timestamp: December 24, 2016, 04:37:05 am
content: I can think of a winner that would cost more than the 200 euro... kind of a Rube Goldberg approach to the ring oscillator.

author: mmagin
author_rank: Frequent Contributor
timestamp: December 30, 2016, 06:14:13 pm
content: Having never done it before (but having had enough experience to make me cautious), I'm really tempted to use this as an excuse to build a non-isolated line-voltage lamp flasher, 555 timer, "capacitive dropper" and shunt regulator for the low voltage stuff, sensitive gate triac.I think I have everything I'd need, except for the triac. Hmm.

author: BU508A
author_rank: Super Contributor
timestamp: July 03, 2017, 06:06:51 am
content: Just bring this up as a reminder. They have there some fancy, cool, weird and crazy stuff. And Mike's lightbulb is really impressive.

author: Howardlong
author_rank: Super Contributor
timestamp: July 20, 2017, 12:27:19 pm
content: Anyone else put in an entry here? My attention was drawn to the competition by Mike's entry.This was mine, gawd knows WTF I was thinking.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: July 20, 2017, 12:36:39 pm
content: Quote from: Howardlong on July 20, 2017, 12:27:19 pmYeah, I think that was what kicked it off afetr not having much publicity previously - that was the main reason I did it.

author: pknoe3lh
author_rank: Regular Contributor
timestamp: July 20, 2017, 03:06:32 pm
content: This video makes me think I don't want to enter ...https://youtu.be/ouAXAD5GxCs

author: FrankBuss
author_rank: Unknown
timestamp: July 26, 2017, 11:45:51 am
content: So this is my entryFor detailed description, source code etc. see here:https://hackaday.io/project/26126-touch-lamp

author: zackattack303
author_rank: Newbie
timestamp: July 26, 2017, 03:42:51 pm
content: This is really cool FrankBuss! Well done.

author: FrankBuss
author_rank: Unknown
timestamp: July 26, 2017, 04:09:48 pm
content: Thanks. The judges will have a hard time, there are many entries with unique ideas. I couldn't decide a winner.

author: Howardlong
author_rank: Super Contributor
timestamp: July 29, 2017, 09:24:05 pm
content: My favourite so far is "Four Candles", a Peltier based device powered by candles.https://youtu.be/7TBxQuIb-Ek

author: Howardlong
author_rank: Super Contributor
timestamp: July 29, 2017, 09:25:16 pm
content: Here's a second one of mine, "Pulse-o-tron".https://youtu.be/yWravW6Uu5Y

author: MK14
author_rank: Super Contributor
timestamp: July 29, 2017, 10:02:16 pm
content: I've NO connection with the following video.It seems rather good. A Neon flasher, uses a valve/tube to switch a relay to control the lamp.

author: jaromir
author_rank: Unknown
timestamp: July 31, 2017, 06:29:29 pm
content: And here is my entry, with no timing capacitor - using the lightbulb itself as main timing device.pdf with some more explanationhttps://drive.google.com/file/d/0B7bWXJ-9TfE5WjNhVFBEa0hHZm8/view?pageId=109602901961672216857

author: ivaylo
author_rank: Frequent Contributor
timestamp: July 31, 2017, 06:45:31 pm
content: +1 for using a TESLA transistor

author: RoGeorge
author_rank: Super Contributor
timestamp: August 01, 2017, 01:48:03 am
content: Here are my entries:First one was made mainly to learn how to make and edit a video with Blender.Also, it was quite a surprise to find such a rare type of light bulb in one of my own junk boxes. I didn't knew such a thing even exists, never mind that I was having one:https://youtu.be/p2XPMuDMxwoThe video for the real entry was only half-edited, and sent in the last minute before the deadline:https://youtu.be/V7gQh1KFjqcThere was no time to add explanations in the second video, so it's probably dead-boring to watch.It is made by 2 identical motors, each with 4 magnets on top, and a reed switch nearby. The 2 magnetic reed switches are in series with a light bulb and a battery. The motors rotate the magnets they have on top of their axle producing a rotating magnetic field.When the motors are at the right distance from the switches, the reed contacts start to vibrate in the rhythm of the rotating magnetic field. Motors rotate very fast, probably around 2000 RPM.The trick is that each motor has a slightly different RPM. The reed switches are in series, so they emulate a logic AND for the bulb. Boolean AND is the same as multiplication. Multiplying RPM1 and RPM2 corresponding frequencies will produce two spectral components with the frequency RPM1 + RPM2 and RPM1 - RPM2, because cos(x)cos(y)=1/2[cos(x?y)+cos(x+y)]As a result, the bulb filament will see two frequencies, RPM1 + RPM2, and another frequency RPM1 - RPM2. Because the filament has thermal inertia, it will act as a low pass filter, and it will attenuate the component of frequency RPM1 + RPM2.On the contrary, RPM1 - RPM2 will be in the range of about 1 Hz, and the light bulb will flash in the rhythm of RPM1 - RPM2.In the end, we managed to produce a 1 Hz oscillation started from 2 motors at about 2000 RPM.Same technique as used in telecommunication for frequency shifting, frequency modulation, software define radios, etc., but applied to an incandescent light bulb with the help of 2 reed switches.

author: chefkoch84
author_rank: Contributor
timestamp: August 01, 2017, 10:13:28 am
content: Here is our entry:The Flashing Light Prize 2017 - Crookes radiometerWe use a Croocks Radiometer for frequency control, which is powered by the blinking light source itself.We measure the speed by projecting a shadow with a red LED - (this is not powerful enough to power the radiometer itself).We measure the changes in brightness using a photo-resistor. A little smoothing is done by an ESP8266 and the light is finally switched by a simple relay.What perhaps does not really come out in that video:The blinking frequency is influence obviously by the rate of the radiometers spinning; the average ingress power, so the wattage of the lamp, the distance, the style of reflector ... etc.There is also a lower limit to the rotation ...the gas-friction of the wheel in there will cause the speed decrease in every dark-phase ... if it cannot reach the next bright-phase by momentum, the system will stay off forever.(We demonstrate this at the very end of the video)The resulting situation is a little bit an unstable equilibrium.All this is surprisingly sensitive to little changes. Either getting too fast or stopping eventually ("too fast” for the price is faster than 2Hz)One could ask if this is possible without the probe-light LED- so the only light source in the system is the light that also gets blinked---> Yes this is possible, but here everything is extremely sensitive to small changes.Probably a bigger lightbulb with huge thermal mass in the filament would overcome this problem a bit.Also for this setup, one has to be aware that the radiometer is still controlling the flash rate. A direct back coupling of the blinking light itself could happen, and that is not easy to overcome.

author: Brumby
author_rank: Unknown
timestamp: August 02, 2017, 01:33:38 am
content: Quote from: RoGeorge on August 01, 2017, 01:48:03 amVery common globe for Christmas lights. You would have a string of twenty 12V globes in series (for 240V mains) and with 20 normal globes, they would all stay on. Replace one of those with the flasher globe and the whole string would flash on and off as one.My mother hated the Bang - on and Bang - off starkness of this arrangement. We also had an aluminium tree at the time, which wasn't the sort of place to put a mains powered string of Christmas lights - so I came up with a solution. I cut off the mains plug and wove a slim 2 conductor figure 8 cable along the length together with a strand of tinsel for camouflage. I then linked a point between every second globe to one of these conductors - alternating between them as I went along the length. This gave me 10 sets of 24V lighting in parallel. I then scrounged all the flashing globes I could find (3 of them) and put one in each of 3 sets. Fed from a 24V supply, I now had 7 pairs of fixed lights and 3 pairs of flashing ones - and since the flashing ones were independent, their differing time constants gave a randomness to the display.

author: FrankBuss
author_rank: Unknown
timestamp: August 08, 2017, 01:46:21 pm
content: Winner for 2017:

author: Brumby
author_rank: Unknown
timestamp: August 09, 2017, 05:14:32 am
content: That is a worthy winner.Never seen a coil used in reverse before.

author: kalel
author_rank: Frequent Contributor
timestamp: August 09, 2017, 05:18:48 am
content: Yes, it's a great one.Just curious, was there something about 5 minutes running time on video? Some people mentioned in their videos that it should run for 5 minutes (unless I mixed it up with something else).

author: ivaylo
author_rank: Frequent Contributor
timestamp: August 09, 2017, 06:28:44 am
content: Your setup should be able to run for 5 minutes. If there is no doubt that it can, no need to shoot all 5 min.

author: Howardlong
author_rank: Super Contributor
timestamp: August 11, 2017, 09:11:03 am
content: Quote from: ivaylo on August 09, 2017, 06:28:44 amThat was pretty much my understanding too, my first vid had it running for five minutes in real time, but my second didn't bother, you wouldn't believe how boring it is waiting, and frankly not many are going to watch the whole thing. Others did timelapse, which is a good compromise IMHO.

author: kalel
author_rank: Frequent Contributor
timestamp: August 11, 2017, 09:24:33 am
content: Quote from: Howardlong on August 11, 2017, 09:11:03 amYes, that makes perfect sense. It's more interesting to see the original contraptions than watching the flashing itself.

author: mikeselectricstuff
author_rank: Super Contributor
timestamp: September 18, 2017, 09:43:49 am
content: 2018 contest announcedhttps://www.flashinglightprize.com/

author: RoGeorge
author_rank: Super Contributor
timestamp: September 18, 2017, 03:42:41 pm
content: IMHO, the rules for 2018 are too restrictive.Why limiting it to Neon gas? And only 1Hz, and duty cycle only 50%?Most lightning tubes are Mercury or Sodium based, or some other gas mixture. Neon is not used in signs since the 50's, except maybe in art installations.

author: Brumby
author_rank: Unknown
timestamp: September 19, 2017, 03:39:24 am
content: The frequency and duty cycle aren't new ideas. They've been included in the past. For the gas discharge situation, this eliminates trivial solutions where a capacitor charges up until breakdown occurs, giving a brief flash. You will have to design something a little more sophisticated.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 19, 2017, 07:16:20 am
content: I see nothing wrong with "trivial" solutions.It will be terrible boring if everybody will start using FPGAs or microcontrollers for precise timing and precise firing of the gas.This competition was great last year especially for allowing very crude solutions to compete with very elaborated ones. That was the main reason for so many crazy approaches in the 2017 entries.1Hz, 50% duty is very limiting, in the sense that it will eliminate most of the simple but very ingenious solutions, and will require more complex but standard approaches, in order to achieve the required timing. Also, 1Hz with what precision, an RC timing, Quartz, Rubidium?A range of frequencies and duty factors is what I would have liked to see, as it was in 2017. To recap:A permissive range will allow more imaginative solutions.A restrictive range will lead to standard solutions.This competition is all about imagination.Then the gas, mostly Neon only is very limiting. I would have liked to see any kind of gas allowed.

author: Brumby
author_rank: Unknown
timestamp: September 19, 2017, 07:30:17 am
content: You want more relaxed rules? Ok ... How's this:1. Build a circuit.

author: RoGeorge
author_rank: Super Contributor
timestamp: September 19, 2017, 08:01:18 am
content: OK then, it seems that I got it wrong. Sorry.Best wishes with the 2018 edition.

author: Howardlong
author_rank: Super Contributor
timestamp: September 24, 2017, 09:20:06 am
content: Here is a 2018 entry of mine, flashing a neon bulb off a 1.5v AAA cell.

author: SeanB
author_rank: Super Contributor
timestamp: September 24, 2017, 10:04:00 am
content: Remember a lot of lamp types also use neon as a fill gas, not necessarily because they want the red light, but because it performs another function. Some fluorescent lamp starters use neon in a Penning mixture ( generally the S151 low voltage ones) and almost all sodium lamps, both HPS and LPS, use neon as a fill gas part as well.