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View Full Version : Backlighting and 12V Power Supplies.



Holclo
03-26-2008, 06:18 PM
I am at the stage where I am backlighting my panels using LED strips and considering Cold Cathode Tubes. Now on E-buyer I can purchase a 500W power supply with 4 Molex connectors for about £13. Sounds good to me but as I do not really understand electronics is this a good idea and the way to go? At the moment I am using one 12v adaptor to run the 24LED strip that I am using but I need lots more!!
Bill

Trevor Hale
03-26-2008, 07:09 PM
Hey there.

If I were you I would bank on 45 - 50mA per led X 24 Led's = aprox 1 - 1.2 Amps per strip. a 500W power supply is probably capable of supplying around15 - 20 or so Amps at 12V.

Do you think that would meet your requirements?

Best regards,

Trev

ian@737ng.co.uk
03-27-2008, 12:48 AM
hello captain.....
trevor is right. i dont have the patience to sit there soldering 100's of led's and resistors, so i went down a different route. i used 12v MES bulbs instead on an ATX 500w power supply. i ended up with 12 to backlight my overhead, so for your purpose, i dont think you will have any issues.
attached is a picture of the MES bulbs when i was wiring them into my old overhead. led's draw so much less power than a bulb, so i guess you will not have any issues.
have a great day .... ian

Holclo
03-27-2008, 03:43 AM
Thank you guys. Just to prove I am a real beginner when I get this power supply which has 4 molex connectors does this mean I can only attach 4 LED strips or 4 Cold Cathobe Tubes. Can I purchase "molex" connectors to attach to the LED wires so that I can connect it to the power supply. It is obvious that I have never even seen a PSU!!
Bill:???:

mpl330
03-27-2008, 06:44 AM
Bill,

Its possible to buy molex Y splitters that take one molex lead and this 'splits' it to give you 2.

I've ordered some cold cathode tubes myself this week for back lighting (also from E-buyer and only just over 2 pounds for 2 :grin: ) - I'll update to let you know what connections they have...

Regards
Mike

Holclo
03-27-2008, 07:49 AM
Thanks Mike. I will be away from my computer for most of next week but will look forward to your observations. I think cold catobe from ebuyer come with molex connectors and a switch. I am thinking of ordering red. What have you ordered? Very interested to hear your opinions. The postage (courier) is very expensive. £8.90 to deliver a £4 order - that is why I am also going to purchase the PSU at the same time - postage only goes up to£9+.
Bill

Trevor Hale
03-27-2008, 08:03 AM
Thank you guys. Just to prove I am a real beginner when I get this power supply which has 4 molex connectors does this mean I can only attach 4 LED strips or 4 Cold Cathobe Tubes. Can I purchase "molex" connectors to attach to the LED wires so that I can connect it to the power supply. It is obvious that I have never even seen a PSU!!
Bill:???:


Hi Bill, actually all those molex connectors are wired in parallel inside the psu. Keep in mind in order to get the psu to power up I beleive you will have to find the Green wire and connect it to ground. (a black wire). Take one of the large molex connectors and cut the Black and Yellow wire off of the molex. (The Black next to the yellow)

Wire all your strips to the black and yellow and use solder or wirenuts to secure them.

Don't waste your time messing with the molex connectors.

Best regards,

Trev

mpl330
03-27-2008, 09:17 AM
Trev,

I was thinking about cutting the molex connectors off and then connecting 2 or 3 cathodes (via a switch) to one pair of cables (+ve & -ve) from where i've cut it off - shouldnt be any issues doing that should there?

Thanks
Mike

Trevor Hale
03-27-2008, 10:22 AM
Nope, No problems at all.. If I understand you right :)

Holclo
03-27-2008, 01:46 PM
Ah right I think I need to clarify and possibly Trev will be answering Mikes points as well. What I was thinking was to use the new PSU outside the computer and simply for providing 12v for the backlighting and nothing else. This would be to save having a number of small 240v to 12v adaptors cluttering up my power extensions (already have about 12 different plugs (monitors, printers, throttles usb ports etc)
Bill

mpl330
03-27-2008, 02:36 PM
Bill,

Thats what I'm doing. I have a PC PSU for powering my interface cards and will also use it for the backlighting.
As Trev says you just need to short out 2 pins on the main connector (the one that plugs onto a motherboard) to get it to fire up, as a temporary measure I use a bent paper clip (maybe not the best idea but I am aware of it and it works).
It should then be supplying 5v & 12v on the molex connectors (or wires if you cut the connector off;))

Had an email advising the cathodes are on their way so will let you know what they are like. I went for white as my panels have a colour to them for backlighting.
Cheers
Mike

Tim
03-27-2008, 03:10 PM
This probably won't help in your situation, but still good information.

http://web2.murraystate.edu/andy.batts/ps/PowerSupply.htm

I used this site when I modified a PSU for my sim.

Regards,

TIM

Trevor Hale
03-27-2008, 03:14 PM
Mike and Bill,

Sorry Bill was right, I confused the two of you there for a minute. Bill if you read my last post to you, you should be good to go. And If you have any questions regarding that, please post again. I will try to make it a little more clear.


Mike, as for you. I was saying that I think i understood what you wanted to do with the -ve and +ve stuff LOL and it sounded right.

Does that help? LOL

mpl330
03-27-2008, 04:11 PM
LOL - well I understood what you meant Trev! (I think :p)
Thanks

philouk
03-28-2008, 12:17 PM
Has anyone tried EL Wire? I have used it on my MIP and it looks great and very quick and easey to use.

mpl330
03-29-2008, 07:27 AM
What's EL wire?

Cathodes have arrived - they plug into a standard molex if you don't want to cut them off and have an adapter so you can plug other molex connectors into it so it doesnt 'use up' the molex.
Only thing at the moment is one unit comes with 2 strips but they are joined together (I thought they would be seperate) - will investigate if I can split them without breaking...

Cheers
Mike

Holclo
03-29-2008, 07:32 AM
OK Mike. Have a look at the "reviews" of these on the ebuyer site. I think I recall someone posting there about separating the tubes. How do they look when lit - are they too powerful for backlighting or are they goode?
Bill

philouk
03-29-2008, 08:12 AM
Hi Mike,
E L wire is a 2.5mm plastic coated wire that can be supplied up to 10m in length
in several colours ( I used white) it bends like ordenary wire. I have bent it round 4mm curve with no problems it stays in shape to how you bend it.
It can becut at any point and made of to a connection its powerd by a small inverter which is powerd by a 12v DC transformer.
I liked it because it matches the back lighting in the CP Flihgt MCP.
check out the web site WWW.EARLSMANN.CO.UK
They are very helpfull people if you want to know more technical info.

mpl330
03-29-2008, 08:53 AM
Phil, thanks for the link - will check it out, sounds interesting. Principle sounds very similar to the cathode tubes - but flexible...

Bill, not sure whether they will be too bright, if anything they may not be bright enough but to be fair I havent tried properly yet. With the way my parts are set for backlighting I dont think it will shine through enough in daylight but at night I'm sure it will be fine.
Will update once tried further and it looks like a little bit of screwdriver action will split them!
Cheers
Mike

ian@737ng.co.uk
03-30-2008, 01:01 AM
maybe something like this on e-bay will help you out. much more powerful than an ATX power supply.
http://cgi.ebay.co.uk/ws/eBayISAPI.dll?ViewItem&item=230236633706&ssPageName=MERC_VIC_ReBay_Pr4_PcY_BIN_Stores_IT&refitem=350040405529&itemcount=4&refwidgetloc=closed_view_item&usedrule1=CategoryProximity&refwidgettype=cross_promot_widget&_trksid=p284.m183&_trkparms=its%3DS%252BI%252BSS
or do a search for "12V 13.8V DC 12 Amp Regulated Switching Power Supply"
i've sent for one for my setup.
regards to all .... ian

Holclo
04-03-2008, 02:26 PM
Thanks Ian.
Mike - how have you progressed? Will be ordering tomorrow hopefully but would like to hear your latest impressions before I do.
Bill

mpl330
04-03-2008, 04:44 PM
Hi Bill,

Not had chance to test them properly but:
1 -They are easy to split - hammer and screwdriver did the trick!
2 - I think I need 3 (individuals not sets) to light my pedestal as 2 don't distribute the light enough)
3 - don't seem bad for lighting the under side of the glare

Overall for the price they are good but not amazing - I think I can make them work for me but if I were you I would probably try a set if you are ordering something else anyway before committing to using only these...

Not sure if that helps :???:
Cheers
Mike

Holclo
04-03-2008, 05:09 PM
Thanks Mike. I'll order and have a go.
Bill

Holclo
04-09-2008, 01:55 PM
OK my cold cathobe tubes and power supply have arrived. I just want to check "shorting the wires" before I make a mistake. On opening the PSU I find the "power connector/switch connector" - wired to that are black(neutral I assume), brown(live I assume) and green/yellow (earth as it is also connected to the PSU metal casing). Am I right in connecting the green/yellow to the black.? Then it should power up. The cathodes have molex connectors so I will use them in the meantime.

Going from the molex connectors to the cathodes are a red and black wire. If I am going to insert a (panel) switch, is it inserted on the red wire?
Thank you for your help
Bill

Trevor Hale
04-09-2008, 03:09 PM
Ack! Please Close it up quick :) before you hurt yourself.

You actually shouldn't open anything up.


Close it all back up and don't open it up again LOL :)


Out of the power supply there are several molex connectors with Yellow, red and black, black on them...

These are where you attach your devices.

Red/Black for +5v
Yellow/Black for +12V

Now one of the connectors (the largest one) that has tones of wires going into it has a green wire on it Cut this wire off, and attach it to any black wire.

Then plug it in and the power supply will then start.

Trev

Holclo
04-09-2008, 03:36 PM
Thank goodness I was flying whilst waiting for a reply!!! OK I will quickly close up the PSU. I see the connector with loads of wires attached - it has amongst others one green and 8 blacks. So I am going to cut the green and one of the blacks and attach them to each other -...OK?
Bill
Feel like Sean Connery in one of the Bond Movies!!

Trevor Hale
04-09-2008, 03:54 PM
Yup. thats works perfect. Make sure that you have it unplugged before you cut or attach the wires together.

Then once your done and it is all safe, plug it in and you will hear the fan on the PS start. this means your getting the power everywhere.

You will not use the big connector block for anything else.

Trev

Trevor Hale
04-09-2008, 03:55 PM
Feel like Sean Connery in one of the Bond Movies!!

ROFL... I bet, well if you had done it the way you wanted you would have been like Jeff bridges in BLOWN AWAY!

Trevor Hale
04-09-2008, 03:57 PM
Going from the molex connectors to the cathodes are a red and black wire. If I am going to insert a (panel) switch, is it inserted on the red wire?
Thank you for your help
Bill

If you want, it is always best to switch the positive side yes. so you would cut the red wire in half, and put each end of the red wire to each post on your switch.

Trev

Holclo
04-09-2008, 04:24 PM
Thank you Trevor. Now we are all lit up - the cathodes that is -not me!! These appear to be very useful and dare I say it a simple solution to some backlighting problems. They are 12 inches long (I believe they can be got in 4 inch lengths - much better) and come with stickers attached for mounting plus an extension connection to attach the next one which avoids using up more molex connectors.They come in a variety of colours. I have red and white. The red looks a bit pinky though.Only £2 each. It will be tomorrow before I get them fitted to the MIP. Going to have a few beer after that feat of electrical genius!!!
Bill

Trevor Hale
04-09-2008, 04:28 PM
Great to hear Bill.

Keep us posted and try to take some pictures.

Trev

Holclo
04-09-2008, 04:37 PM
Will do Trevor. Just now my main problem is a PMDG 737-700 that is performing great 35+FPS at 20000feet but about 6FPS during the real action of TO and Landing and then back to 30FPS taxiing. Frustrating. Gonna post about this soon if I can't solve it.
Bill

Trevor Hale
04-09-2008, 04:40 PM
Before you post about it. do a search in our forum for "FSAUTOSTART"

there is a new version out of this called something different now. Basically you run it before starting flightsim and it sloves the studders. Doesn't hurt to give it a try.

Trev

Holclo
04-09-2008, 04:59 PM
Have the new version called AlacrityPC. maybe I'm not using it correctly but it hasn't given me much improvement. Have just uninstalled FSX (I'm running FS9) but that hasn't helped either - some said it did. It may be Redux 3D Lights which I added a few weeks ago - about to uninstall it just to see if that helps. It is annoying as I have recently added Engravity Captain and Centre Panels for the 737NG and TH2GO plus 2 extra monitors and have ended u with a slide show - I'm using Gywn's set up. Really should be no problem but computers can be very frustrating at times.
Bill

Trevor Hale
04-09-2008, 05:08 PM
That they can Bill.

Good luck and talk to you soon.

Trev

mpl330
04-09-2008, 05:20 PM
Bill,

Glad to hear you got the cathodes working - wasnt sure if they would be bright enough for you...

Good luck with solving the 'stutters' - there was a link posted in another thread recently that links to avsim about tweaking your system that may help too...

Cheers
Mike