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Main => Builders Discussions => Topic started by: jackpilot on February 07, 2011, 10:16:32 AM

Title: Backlighting with LED stripes
Post by: jackpilot on February 07, 2011, 10:16:32 AM
First, a big thank you to Scott for "enlightening" me on the subject.
Here are some pics from a test I did today.
I use a orangy red acetate behind the panel and the final result is very interesting.
Color is a little bit more redish than the photo shows , and real close to IBLs color,  the LED stripe (12v) is dimmable.
BTW I used a Ebay new surplus 20hms 3A pot for dimming. It works and does not heat at all.
Maybe it is not good to use that? Please advise.
Here are the pics:
Title: Re: Backlighting with LED stripes
Post by: matta757 on February 07, 2011, 10:22:45 AM
Looks great!
Title: Re: Backlighting with LED stripes
Post by: XOrionFE on February 07, 2011, 06:12:43 PM
wow, nice. brilliant idea with the red acetate Jack.  from the picture it is a close match to the real deal.

Scott
Title: Re: Backlighting with LED stripes
Post by: Kennair on February 07, 2011, 07:48:53 PM
Simple and easy way to backlight Jack, thanks.

As for the coloured film background, I did similar with my EFIS and MCP but used a tip from Claude Keiffer from his A320 build (http://translate.google.com/translate?js=y&prev=_t&hl=en&ie=UTF-8&layout=1&eotf=1&u=http%3A%2F%2Fwww.simu320.fr%2Fsommaire.htm&sl=fr&tl=en).  To get a really good orange colour use one layer of orange and one layer of yellow gel.  I bought sheets of lighting gel off ebay which are tougher than your hobby shop type of cellophane (you may well have done the same).  It's a little extra work but results in a strong colour glow without hindering light intensity.

Cheers,

Ken.
Title: Re: Backlighting with LED stripes
Post by: jackpilot on February 08, 2011, 05:52:17 AM
The color is also adjustable depending on cool/warm white leds.
I used warm.

Note :would be easier to order an IBL set!!!! but I got those panels too early I guess  ;)
Thanks for the appreciation Guys.

Oh, and what do you think of the pot dimmer???? Am I right?
Title: Re: Backlighting with LED stripes
Post by: Joe Lavery on February 08, 2011, 06:31:11 AM
Hi Jack,

First of all I'm no expert, but a pal of mine who is an electronics wiz said that the circuit below was a better, (more elegant he said) solution for a dimmer.

I built the circuit on vero board and it's been in place over a year now and doesn't get hot at all, although I got a decent transistor in a can, rather than the usual plastic variety.

Hope that's helpful.

Joe.

Title: Re: Backlighting with LED stripes
Post by: jackpilot on February 08, 2011, 07:24:41 AM
Wilco..thank you.
Title: Re: Backlighting with LED stripes
Post by: Emesis on February 08, 2011, 02:21:11 PM
Jack,

These are the ones that I use with my LED strips, they work great and are cheap!

http://cgi.ebay.com/LED-Bulb-Dimmer-Adjustable-Brightness-Controller-DC-12V-/300522532102?pt=LH_DefaultDomain_0&hash=item45f889ed06 (http://cgi.ebay.com/LED-Bulb-Dimmer-Adjustable-Brightness-Controller-DC-12V-/300522532102?pt=LH_DefaultDomain_0&hash=item45f889ed06)

Cheers
Title: Re: Backlighting with LED stripes
Post by: jackpilot on February 08, 2011, 02:44:10 PM
Grrrrrrr. Stupid EBay   cant access from Canada due to legal restrictions.....Hey Mau, add the dimmers to the list of potential weapons!!!!

Edit: found that one . Same?
http://cgi.ebay.com/PWM-Dimmer-Dimming-Controller-LED-Light-Strip-12V-/110644323673?pt=LH_DefaultDomain_0&hash=item19c2ea6559
Title: Re: Backlighting with LED stripes
Post by: Emesis on February 08, 2011, 03:06:41 PM
Yeah Jack it's the same one, if you keep looking on Ebay you might find it a little cheaper. I believe that Scott posted a link a few days ago to the same type of dimmers from a different place.

Rand

Title: Re: Backlighting with LED stripes
Post by: Garys on February 08, 2011, 03:56:18 PM
No problems getting these into Canada Jack. Beeen using one for about a month and just ordered a couple more. Good seller.

http://cgi.ebay.com/LED-Bulb-Dimmer-Adjustable-Brightness-Controller-DC-12V-/180612444849?pt=LH_DefaultDomain_0&hash=item2a0d5732b1
Title: Re: Backlighting with LED stripes
Post by: jackpilot on February 08, 2011, 04:33:18 PM
Do you think that they can handle a ¼mile of stripes...have to do the entire MIP...and the overhead ..and the pedestal...
Title: Re: Backlighting with LED stripes
Post by: Garys on February 08, 2011, 05:18:56 PM
LOL... it certainly does add up. these are rated to 8 amps and I have seen 5m led strips ranging from 0.4 amps/meter to 1.2 amps so you can have alot of lights running of one. The only reason I ordered more was to adjust the areas seperately as well.
Title: Re: Backlighting with LED stripes
Post by: saabpilot on February 08, 2011, 08:13:55 PM
 Hi, I will use LED strips too for my OH.

Great tip with the colored sheets.  I spoke with a German guy at the Lelystad simshow and he recommended to "color" the white LEDs with glasspaint (yellow+red), but the idea with foils is easier I believe.
Regarding the 1$ dimmers from Hong Kong, they are superb for the 12V  LED strips. You can easily detach the PC board and the pot from the "box".

The PC board and pot are connected with a 10 cm cable so very easy to place the board.  Rated for 8A so you will never have any problems even if you run ALL backlight LED:s from only one dimmer.

Best,
Bjorn in Sweden
Title: Re: Backlighting with LED stripes
Post by: NeoMorph on February 10, 2011, 12:53:33 AM
Quote from: Joe Lavery on February 08, 2011, 06:31:11 AM
Hi Jack,

First of all I'm no expert, but a pal of mine who is an electronics wiz said that the circuit below was a better, (more elegant he said) solution for a dimmer.

I built the circuit on vero board and it's been in place over a year now and doesn't get hot at all, although I got a decent transistor in a can, rather than the usual plastic variety.

Hope that's helpful.

Joe.

Damn, those 555 timers are so darned useful... Never would have thought of using it for an LED dimmer but as most seven segment displays are in essence dimmed like that (the individual numbers are actually lit a lot brighter than the final multiplexed display) then it really does make sense. The more LED's you use though, the dimmer the whole string of LED's would be though.
Title: Re: Backlighting with LED stripes
Post by: Joe Lavery on February 11, 2011, 12:01:21 PM
As I understand it a multiplexed seven segment display is normally controlled by a PIC. The PIC is capable of turning each segment on and off again many times a second, much faster than the human eye can see. So in fact in this scenario only one segment is ever lit at one time. It's the persistence of vision and the very high speed that makes the segments appear to be lit continuously.

I hope that makes sense, as I said earlier I'm no expert but I've been messing about with seven segment displays and PICs to get a working 737 style clock.

Joe.
Title: Re: Backlighting with LED stripes
Post by: NeoMorph on February 11, 2011, 08:23:05 PM
You are right which was why I said I had not seen a 555 timer used that way.

Most people think that all the segments on their LED bedside clocks are lit at once because all the numbers are lit. If they were to see a single digit lit without the multiplexing they would see it loads brighter than the multiplexed display  which is basically how the dimmer seems to be working here.

Seeing it work in a video is going to be interesting as cameras work different to the eye. Was watching a video of a Bonanza yesterday and it looked like there were venetian blinds at the front instead of a prop heh.