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Discussion Starter · #1 ·
I am trying to source LEDs 12v 5mm white(clear) super brilliance!

Can any member help me out with UK supplier address - thank you.
 

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QUOTE (double00 @ 21 Jun 2007, 16:32) <{POST_SNAPBACK}>I am trying to source LEDs 12v 5mm white(clear) super brilliance!

Can any member help me out with UK supplier address - thank you.

Ho Doubleoo I have asked this before and for the life of me I can't find the thread but there were a number of places mentioned. If you type in LED's in the search box it bring up a number of articles and more important a number of suppliers. There is alway Maplins and www.rapidonline.com. I have not used either personally for LED's but it gives you a good place to start to see what is available and at what cost.

Good hunting

Chris
 

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I use Farnell. They take credit cards online and the delivery is usually next day (inc saturday) by post. This search URI for white LEDs should get you started.

David
 

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DoubleOO, as Chris has already said Rapid are a very good source and one I can personally vouch for having used them for several years. From a modellers point of view Bromsgrove Models are another good source. They are a bit on the expensive side but do offer a good selection of LED's and also specialise in model railway electronic trickery.

Bromsgrove Models : http://www.bromsgrovemodels.co.uk/brmodsindex.html

Rapid Electronics (5mm LEDs) : http://www.rapidonline.com/products.aspx?t...;tier3=5mm+LEDs

Steve
 

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Discussion Starter · #7 ·
I am a little unsure when applying voltage to a LED - positive (+) is connected to the Anode or the Cathode(K)
 

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Discussion Starter · #8 ·
Gofer - I found that Rapidonline has the most extensive list of LEDs. I have ordered what I hope are the correct LEDs for my requirements from Rapidonline. I find Rapidonline postage rate rather high.
 

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doubleOO, Rapid are a bit expensive on postage if you use them for anything other than bulk purchases. If you buy more than £25 worth (excluding vat) postage is free. I wait until I need at least that amount before ordering. What helps is that I have an arrangement with a few like minded mates and we simply let each other know when we want some bits and pieces and when the total comes up to or over the free postage limit I place an accumulative order. Works well for us. I can understand that if your only ordering a few LED's and resistors the postage does make you wince a bit.

Oh and by the way, positive is connected to the anode (long lead) and always use a series current limiting resistor. See the link Chris and baykal have given you.

Steve.
 

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Chris,

I'm sorry, I simply didn't see your link when posting mine.
When I saw doubleOO's question my reflex's just went to this site which I keep it in my favorites cause I find it very helpful.
Sorry again.

Baykal
 

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Discussion Starter · #13 ·
Thanks again for information on the correct soldering of LEDs. Kpc.free.uk.com web site - I was unable to locate any references on correct way to connect voltage polarity to a LED. Gofer, thanks for information for correct connection.
I visited the Perth model railway exhibition today and obtained from one dealer a 5mm 12v blue flashing LED at a price of £2.50 for one off - rather expensive - worse, in connecting the LED to a 10v supply, LED illuminated OK, but no flashing! Though I was assured LED was a flashing type, after closer examination, LED appears to be just an ordinary LED.
 

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doubleOO, sorry to hear of your bad experience. It may not be immediately obvious that the LED is a flashing type as the integrated circuit (IC) which causes the LED to flash is built into the body and may not be visible. Also, I've never used one but I'm sure flashing LED's don't require a series resistor as the integral IC takes care of current limiting.

As regards the link Chris and baykal gave you the connection information is on the very first page under the heading 'connecting and soldering'.

Steve
 

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QUOTE (ebaykal @ 23 Jun 2007, 21:30) <{POST_SNAPBACK}>Chris,

I'm sorry, I simply didn't see your link when posting mine.
When I saw doubleOO's question my reflex's just went to this site which I keep it in my favorites cause I find it very helpful.
Sorry again.

Baykal
Baykal - No problems in fact you may have put me onto it in the frst place when I was asking a similiar question a few weeks ago. It is a very useful site hence it is also in my favourites as well.. Must admit still haven't got round to fitting any in my loco's as yet, must pluck up the courage.

Chris
 

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Discussion Starter · #16 ·
Contrary to all I have heard or read - the supposed blue coloured flashing LED in question was connected anode to (+) then anode to (-), each time LED illuminated without any failure and still functions correctly, that is still without the "flashing feature".
Now can this 12v LED prove that connecting voltage to the incorrect leg of the LED is not crucial?
I have no wish to prove as correct or incorrect but rather stick to the rule anode(+) cathode(-).
 
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