Force FX board with LED string and Power Xtender?

A couple of years ago, I got the clever idea of converting a Force FX Vader to a bright LED string with a removable blade. Stupid me, I did not account for the fact that the board would not provide enough current to 66 red 5mm LEDs (VF=2.0-2.2V, 30mA). Needless to say, it didn't work. I can't remember exactly, but I seem to recall that some segments lit up, while others wouldn't light up at all. So I just set aside that gorgeous string, the fairly slick 3/4" blade I made for it, and the TCSS Vader conversion kit that I modded specifically for a plug-in 3/4" string blade. Well, I just hauled it out, was thinking what a waste it is, and then it occurred to me that I might be able to do something with Power Xtenders. Has anyone tried using Power Xtenders with a Force FX board and a scrolling string blade? Am I right in thinking that I would need a separate Power Xtender for each segment? And would I need a separate resistor for each LED? I don't see how I could use a single resistor for a string of eleven 30mA red LEDs wired serially, using a standard Force FX 4.5V battery pack. Come to think of it, is it even possible to power such a beast with just 4.5V? Should I replace the Force FX battery pack with a 7.4V li-ion pack?

My brain hurts…. :(

You could run the whole string with the 4.5v I think, I wouldn't wire them series though, you would need a resistor on each led. Hopefully someone with better skills will chime in, calling Azmaria, or Erv. I would solder all the connections on the MR together like you were doing a lux upgrade, wire the string in parallel, then use a single PeX, and if I did my math right a 1.2 ohm 5 watt.

I have wondered if removing some of the resistors already in place on the MR boards and replacing with jumpers to up the current for more compact solutions like that. I studied Don se Wions solution on his TCSS contest saber, he appeared to have added a transistor in order to achieve more current. Maybe he will chime in here as well.

Look here http://forums.thecustomsabershop.com...iring-Diagrams

The posts down there's a diagram of all the wires. From what I understand looking at this, there's a single positive wire that would go to each segment, and then each segment has its own negative and you can see on the board they numbered. Now what you would need to figure out, is segment number 1 the bottom of the blade or the top of the blade (maybe someone else can provide that answer)? Once you figure that out then I would think they should just wire back up in numerical order to produce the scroll effect.

As far as should the string be series or parallel, or series witin the segment and the segment in parallel? I don't know, I'll let someone with more experience than I speculate upon that.

Hope this helps you out.

Ari-Jaq, I think you meant "wire the string in series," not "wire the string in parallel," didn't you? That's the only way it would make sense to solder all the leads together and use a single Power Xtender. But to my mind that would pretty much defeat the purpose of making a string at all. I want this to be scrolling.

DarkarNights, what you're talking about is the easy part, which has already been taken care of. I'm talking about getting sufficient power to the string, which the Force FX board can not do on it's own.

When I typed that up, your post contained mention of you having cut all the wires previously and you were asking where the wires needed to be resoldered. I guess you figured that part out and decided to edit your orginal post, thus making my answer look like complete gibberish. :confused:

DarkarNights, I think you meant to respond to someone else's post, because I didn't mention anything like that, and I never edited my original post (as you can see). :D

Whatever, everyone here who has edited a typo knows that if you edit soon after posting, your first edit isn't logged as an edit. I actually spent time seeking an answer to a question you asked and linked to what I found. Only to end up with you playing some kind of game with your posts. I would have expected more civilized behavior from something with your rank.

Huh?
:shock:

Are you saying that I actually asked the question that you said I asked, only to quickly edit it into something completely different, and am now LYING about it?

Why would I do that?

This project has nothing to do with anything you mentioned. I have been taking Force FX boards apart and putting them back together for six years. The information you so generously provided was something I learned in 2008, when you were apparently still in junior high school, or possibly kindergarden, judging by your behavior. Maybe instead of berating me for YOUR mistake, you could try to find the post you THOUGHT you were responding to. There may be someone out there waiting for the response that you mistakenly posted here. Either way, you don't need to come back to this thread anymore. Really. Run along. Scoot.

Sheesh! :roll:

If I really am mistaken, then I humbly apologize. But, I actually did look back at the forum posts that were posted today in an attempt to find the post I refered to, and found nothing. I'm not a child, and I will not be spoken to as such. If I did in fact make an error in mixing up a post, that gives you no right to make a personal attack on me and question my age when you tell me I have errored. I'm finished.

This is what you wrote, after I wrote a perfectly civil response to your first post:

Quote:

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Originally Posted by DarkarNights

Whatever, everyone here who has edited a typo knows that if you edit soon after posting, your first edit isn't logged as an edit. I actually spent time seeking an answer to a question you asked and linked to what I found. Only to end up with you playing some kind of game with your posts. I would have expected more civilized behavior from something with your rank.

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When I called you out for calling me a liar, you responded:

Quote:

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Originally Posted by DarkarNights

If I did in fact make an error in mixing up a post, that gives you no right to make a personal attack on me and question my age when you tell me I have errored. I'm finished.

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Do you see the contradiction here? You did not give me the benefit of the doubt, yet became angered when I responded in kind. I'm glad to hear you are finished here.

My apologies for jumping to a conclusion that was wrong. I was in error.

No problem, I hope we can move on. And I just realized earlier that I failed to thank either you or Ari-Jaq for trying to help. So, a belated thanks to you both.

Your welcome Matt. I have some reading for you. It appears you may not even need the PeX. Check out these two links http://www.slothfurnace.com/sabers/ROTJLuke_02.html http://forums.thecustomsabershop.com...=string+ladder. Yes it scrolls with this setup, you can view Sloth's videos to see it.

Well, never tried anything like this but I think I can make a plan for it.
I'm at work and can't draw a diagram, but I'll try to be a clear as possible.

First of all, you should wire the led strings in parallel for a very simple reason.
Let's say for example that you have a string of 10 LED's in series.
In this case you would need 10x2,2V to light them up, definitely outside the standard battery solution in our applications.
So, you need to wire them in parallel and you will need to find the proper resistor to provide 10x30mA current, 300mA.
With a 4.5V battery the proper resistor would be 7.5 Ohm / 1W.

Obviously these calculations must be adapted to the correct number of LED's you have in each string.

Regarding the board, in other to save the scrolling effect I would remove the 6 transistors and replace them with 6 PEX boards.
In other words, I would wire each R pad of the PEX modules to the pads on the MR board previously used for the transistor's bases.

To identify the proper pads just follow the traces connecting the transistors to the 6 resistors, they are easily identified because they are normally soldered side by side and close to the transistors.
The old MR boards are easier to convert since they use standard transistors with passthrough holes where you can solder the wire for the PEX.
Using the newer MR/Hasbro board with SMD components would be a bit more tricky because they don't have passthrough holes, but it can be done with tiny wires and some fancy soldering.

Last thing I would test after wiring the PEX would be measuring the current given to each string.
If the current going to the LED string is too low and the LED's look dim, I would remove the resistors on the MR board replacing them with jumpers.
The reason for this is that sometimes the current sent to the PEX is not high enough to properly send it in saturation.
Considering the PEX are using MOSFET's this may not be needed, but you never know until you wire everything together and light it up.
This is something I always need to do when using a single TIP41 / TIP42 in MR board mods, but may not be required with MOSFET's.

Ari-Jaq, Don Se Wion, that is precisely the kind of information I was looking for! Thank you so much. Obviously, I need to work on my Search-Fu. I'll let you know how it goes. Thanks again!

What do you think Master Yoda would say about this argument?

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Originally Posted by Evilpancreas

What do you think Master Yoda would say about this argument?

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I was going to give some flippant reply about this leading to that leading to suffering, etc etc, but the only thing I can think of leading to true suffering is deprivation of blood orange sorbet and that just didn't seem to fit.

Matt just do what anyone else would do... Pay someone to do it for you :)



Wish I could help but only thing I can manage is that lack of whit I carry in abundance :p