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aviator84
05-25-2006, 10:03 PM
Hi, I had a couple of questions about the prolight leds. After reading through the posts I think I would like to try my hand at one. What I want to know is since this isn't a luxeon led(at least I don't think) do I still need to use a 5 or 10 degree lens? Also as far as wiring goes could I just use one resistor before the switches, or would I need 3 resistors? I ask this because in order to get certain colors(such as purple) you would need to turn on two switches, right? Any help would be appreciated. This will be my first saber that I am going to build, I have an El vader saber(using a heiland flash) but it was half completed when I bought it. Also, just wanted to thank Strydur for having such an awesome site![:)]

meiv4
05-25-2006, 10:19 PM
your still going to need the lens. and your going to need to use a resistor on each color/switch. thats the very short answer there. i would go find out the values for each resistor... but im lazy. maybe one of the less slackers here can help on that.

hmmm hmmmm whooosh hmmmm whooosh crackel

aviator84
05-25-2006, 10:41 PM
I think I read somewhere that the prolight leds are like three 1 watt leds in one package. Is that right? And if so, which resistor should I use for a 1w led? Thanks! OH, and now that I think about it you would need to now the source voltage right? I was going to use the 4 aa battery holder Strydur offers so that would be 6v.

aviator84
05-25-2006, 11:06 PM
Ok, I think I've finally figured out the resistance calculator I found in a different post. After checking the stats for the led I want to use It says the red is 2.2v, Blue is 3.5v, and Green is 3.5v. The forward current is 350mA. So according to the calculator I need to use a 1.5w resistor for Red, and a 2w resistor for Blue and green. Is this right?

aviator84
05-25-2006, 11:25 PM
Maybe I didn't figure it out. After taking a closer look at what the calculator returned I would need a resistor rated at 8.2ohms, but Tim doesn't sell one that has that rating. Did I do something wrong, or does Tim just not sell the resistor I need?

james3
05-26-2006, 06:31 AM
Ok, slow down and take a deep breath. I like your name so I'm going help you out a little here.

EDIT FUNCTION- After you post there is a little pencil and papaer thingy above your post so that you can come bace and add, delete, change, etc... We all make a double post every once in a while but much more then that and you run the risk of either a xwing on your tail with guns blazin' or a drop in by the elite forces of the De-Railment Unit. Keeping the edit handy makes everyone happy.

Now on to bidness[:D]

You will want to use pots so that you can "tune" the current in order to get the various colors. You could do like Tetematek and use a switch for each color but they do not blend the way that Gelu's saber does.
For the resistor issue Tim may not have in the store the right resistors because he doesn't carry the Prolights and it doesn't seem like Luxeon.
Give me a sec on those calcs...

OK-
http://i43.photobucket.com/albums/e370/Dadof3/diagramrprolight.png

http://i43.photobucket.com/albums/e370/Dadof3/diagrambgprolight.png

http://i43.photobucket.com/albums/e370/Dadof3/diagramr3AAprolight.png

http://i43.photobucket.com/albums/e370/Dadof3/diagrambg3aaprolight.png

This is a few options and once you know what setup you want you can hit the electronic stores or online to get what you need.

BTW, welcome to the boards.

<center>http://i43.photobucket.com/albums/e370/Dadof3/James3sig.jpg</center>

aviator84
05-26-2006, 10:51 AM
Thanks for all the help and the welcome James. I don't post on forums alot so I didn't realize there is an edit button, I'll keep that in mind for the future; I'd hate to have xwing come in guns blazing.[:p] I think I'm pretty close to you, I live in chesterfield which is close to Richmond. But to stay on topic, you mentioned pots. After checking on some potentiometers most of the ones I found are rated at 500 ohms and 1/4 to 1/2 a watt. Would this take the place of the resistor or would I still need resistors and pots? Also, if I need both would I place the resistor before or after the pot? Oh yea, I was looking at the 500 ohm pots b/c that is what Gelu said he used in his saber.

Firebird21
05-26-2006, 11:00 AM
Glad I could help!




Oh wait... I had nothing to do with it...


Oh well, welcome anyways!
http://www.gaownersclub.com/forum/images/smilies/icon_welcome.gif


<center>http://www.yankeetoys.org/lee/TCSSBanner1.jpg</center>

Do-Clo
05-26-2006, 11:08 AM
I would suggest to use both, figure your resister to set your current at max rating of the led, then put your pot in to vary the current and if you should turn the pot to 0 ohms you will not fry your led.

<center>http://i48.photobucket.com/albums/f217/Do-Clo/DoCloSig.jpg</center>
<center><font color="red"><font size="4"><font face="Comic Sans MS">Darth Technous Sith Lord</font id="Comic Sans MS"></font id="size4"></font id="red"></center>
<center><font color="red"><font size="4"><font face="Comic Sans MS">Give yourself to the Dark Side</font id="Comic Sans MS"></font id="size4"></font id="red"></center>

aviator84
05-26-2006, 11:30 AM
Ok, so for Blue or Green I would use an 8.2 ohm 2 watt resistor so that the current going to the led would be 3.5v at 350mA. Would the pots I was looking at work? They are rated 1/2watt at 500 ohms(they are the linear taper kind). Or would I need pots rated at 1watt at 500 ohms? Darn, I wish I had payed more attention in high school when we were learning about circuits[:p]

Do-Clo
05-26-2006, 11:39 AM
You would need to use the 1 watt pots and make sure they are the linear taper and not the audio taper.

<center>http://i48.photobucket.com/albums/f217/Do-Clo/DoCloSig.jpg</center>
<center><font color="red"><font size="4"><font face="Comic Sans MS">Darth Technous Sith Lord</font id="Comic Sans MS"></font id="size4"></font id="red"></center>
<center><font color="red"><font size="4"><font face="Comic Sans MS">Give yourself to the Dark Side</font id="Comic Sans MS"></font id="size4"></font id="red"></center>

aviator84
05-26-2006, 11:54 AM
Thanks Do-Clo, that cleared up all of my questions.

meiv4
05-26-2006, 12:14 PM
if you cant find 500 ohm 1 watt pots mouser has some 1k ohm 1 watt ones. you can either use those as is and it will just dim faster, as in 1 degree turn will dim it about twice as much on the 1k compared to the 500. but if you put 1 1k ohm resistor in parallel with it it will take on a logrithmic curve but have a max of 500 ohm. and the curve is not stong at all. thats what i will be doing as soon as i stop being lazy.

link to pot

http://www.mouser.com/index.cfm?handler=displayproduct&lstdispproductid=261008&e_categoryid=317&e_pcodeid=59400

hmmm hmmmm whooosh hmmmm whooosh crackel

aviator84
05-26-2006, 12:25 PM
Do you think you could show me some sort of wiring diagram for what you are talking about? I'm not quite sure I understand how to wire in a resistor in parallel. If I didn't use the resistor and just wired it in as is would that be a series circuit?[?]

james3
05-26-2006, 12:59 PM
Oh boy! I'm chesterfield too. Are you part of the group from the pizza place last night? My dumb butt got the night wrong and thought it was tonight.

Anywho, back to work[:D]

What meiv is saying is run a resistor across the pot, it doesn't change the rest of the setup just the impedence of the pot so you are still getting the 500 ohms. I know it seems confusing but it's one of those things that you just pick up in time and practice.

<center>http://i43.photobucket.com/albums/e370/Dadof3/James3sig.jpg</center>

tetmatek
05-26-2006, 04:21 PM
You will only use one resistor as the RGB uses a common power with seperate grounds.

http://img61.imageshack.us/img61/713/tetsig5ti.jpg (http://imageshack.us)

tetmatek
05-26-2006, 04:22 PM
Also if you use a MR board you don't need any resistors.


http://img61.imageshack.us/img61/713/tetsig5ti.jpg (http://imageshack.us)

meiv4
05-26-2006, 04:36 PM
do not listen to his dark side lies. since they have diffrent power requirements they require diffrent resistances... and having separate ones on and off would also change the needed resistance, so you cant use just one.

hmmm hmmmm whooosh hmmmm whooosh crackel

aviator84
05-26-2006, 06:16 PM
Thanks for all of the help guys. I didn't make it to the pizza place james, though I did think about it. I ended up having to work, it is nice knowing there are some other star war aficionados out here though. As far as the pots go I am lost again. After looking at some at radio shack, they all have 3 conections, so which connector would I need to hook the resistor to? I'm assuming the connections are power in, power out, and ground. I think I understand know. Assuming connection 1 is power in, connection 2 is out, connection 3 is ground; would I take the resistor and connect it from connection 1 to connection 2?

tetmatek
05-26-2006, 06:32 PM
I take it your close to me. I'll pm ya so you can come by my shop and see one work. That is if your from the chesterfield Va. area.

http://img61.imageshack.us/img61/713/tetsig5ti.jpg (http://imageshack.us)

james3
05-26-2006, 07:00 PM
WOO HOO!!! SABERBUILDING PARTY AT TET'S HOUSE!! You'll learn more that way for sure.

Seriously, you will see it and be like "that's it?"

<center>http://i43.photobucket.com/albums/e370/Dadof3/James3sig.jpg</center>

aviator84
05-26-2006, 07:59 PM
That sounds good, I am from Chesterfield Va. I would love to see one that works so just let me know what a good time is for you and I'll try to get off work. I don't know about you but Sunday afternoon is good for me( I work at Ukrops and we're closed sunday).

aviator84
05-26-2006, 08:48 PM
I found a pot I think will work. This one is rated at 250 ohms at 1 watt and its linear. Here's the link

http://www.alliedelec.com/Search/ProductDetail.asp?SKU=753-2915&SEARCH=&ID=80320&MPN=309N%2DPC+250&DESC=309N%2DPC+250

Do you guys think this would work?

Talking to yourself is perfectly normal... It's when you answer yourself that you need to worry.

meiv4
05-27-2006, 02:29 AM
that should do it. dang wish i had found that earlyer

hmmm hmmmm whooosh hmmmm whooosh crackel