Dim LED on US2.5

[Dingus]

G'day guys,

I recently upgraded my sabre from a simple flashlight setup to now have US2.5 and the blade is considerably dimmer.

The saber is built from all MHS parts.
Electronically it originally had the following parts:
2AA holder
2x Trustfire 14500, 900mAh 3.7V protected
700mA Buckpuck
Green Lux V
Guarded latching switch

Now after a complete rebuild it has the following electronic componentry:
US2.5 MHS Sound/Speaker/Battery holder combo (2AA)
2x Trustfire 14500, 900mAh 3.7V protected
Green Lux V
Guarded Momentry Switch.

I originally thought the overall dimness had to do with the pulse setting on the US2.5 and the 6 foot of cellophane in the blade so I removed the blade and held the blade emitter close to a wall to see how bright the led was. The result was a lot dimmer with the US2.5.

I even changed the Led to a Lux V Blue and it is considerably dimmer than my FX-Sabers Graflex V SE both using the same blades.

I have checked all my solder connections and they appear fine. I have basically connected the 2 switch wires to the momentary switch and the 2 led wires to the Lux V.

This one has me really befuddled. Your help would be appreciated.

[Darth Quin]

Check the batteries that is the simplest answer, though mine just die when they need to be charged. Look for a simple answer first.

[Lord Dottore Matto]

Is the US 2.5 set to Lux V?

[yell0w_lantern]

I have similar problems with a RO Lux III in a brass graflex handle using the store 5 degree optics and a Graflex Shop Blade Holder.
I've tried switching from 4.8 NiMH to 6.4 NiZn batteries as well as swapping the RO for a LEDEngin Deep Red and a Lux III Amber.
The blade is Tim's Special White Poly C and measures about 38 inches.
I've tried every setting with each LED and no progress.

I tried another US 2.5 in a MHS handle with 4.8v NiMH, standard 5 degree optics and special white Poly C on a K2 Cyan, Cree Royal Blue, Lux III Amber, Lux III RO, LEDEngin Amber and K2 Green - all nice and bright.

I assume (take that how you like) that all other things being equal it is either a problem with the particular board OR the way the optics sit in a Graflex Shop blade holder. Now I'm wondering more strongly about the board...

[Kal El Rah]

Have either of you checked to make sure the little blue jumper wire is still attacked on the reverse side of the board, if it is missing or disconnected then that would/could be the problem with your boards.

[Dingus]

Check the batteries that is the simplest answer, though mine just die when they need to be charged. Look for a simple answer first.

Just tried that after my initial post to no avail :(


Is the US 2.5 set to Lux V?

Yes. I have even changed the led to a Lux III Red/Orange, changed the led option on the board setup and it is still dull.


Have either of you checked to make sure the little blue jumper wire is still attacked on the reverse side of the board, if it is missing or disconnected then that would/could be the problem with your boards.

What is this jumper wire? My US2.5 came in the pre assembled battery holder / speaker combo and is glued or taped down to the holder.
EDIT - I carefully looked underneath the board from the side and could see the light blue jumper wire.

[Rhyen Skytracker]

I have used the US 2.5 on 4 sabers so far and haven't had any problems yet. I have used them with a LUX V blue, red Lux III, blue Cree and Green Cree and no problems yet. I can't think of what the problem may be at the moment.

[Novastar]

The only suggestions I have:

* Try a completely different model of an LED--just to check--with the U.S. board. Such as a Lux III. Set the US board correctly and observe...

* Also... have you tested the electronics "alone"? That is, completely unattached to the hilt (except the heatsink of course)?

As to the first suggestion... the point would be to confirm whether or not US is producing a dimmer result on ALL types of LEDs (well not "all", but a few test cases)... and that giving the LED a direct drive setup or some other driver produces better results. And IF SO... yup... I'd say the board is the problem.

You can directly drive a Lux III blue/green/cyan off of a single Li-Ion 3.7v cell (to observe 'well-driven' brightness). And of course, you already know that 7.2v or 7.4v is a perfect voltage to test a Luxeon V.

[Dingus]

Thanks for the input guys, unfortunately nothing seems to work.

Before installing the US2.5 setup in the hilt I wired it all up to test and it worked fine. After installing it in the hilt (i run the quick changer clips on my LED's) I changed the LED to a Lux V Blue, Lux III Red Amber and they are all dull.
I am running a thick walled blade, the same blade before when it was driven off the 1000mA buckpuck.

I just don't know whats going on here it's like i have hit a brick wall.

[Jagahati]

Thanks for the input guys, unfortunately nothing seems to work.

Before installing the US2.5 setup in the hilt I wired it all up to test and it worked fine. After installing it in the hilt (i run the quick changer clips on my LED's) I changed the LED to a Lux V Blue, Lux III Red Amber and they are all dull.
I am running a thick walled blade, the same blade before when it was driven off the 1000mA buckpuck.

I just don't know whats going on here it's like i have hit a brick wall.

This to me sounds like a short. If it worked before you put it in the hilt then mysteriously became dimmer one it got put in the hilt then that sounds like you are getting some type of shorting with the hilt itself.

I would remove the electronics from the hilt re-test and if they work there you need to find that short.

[Dingus]

I just dismantled the saber, and rewired it outside the hilt to rule out a short.
The blade was still dim.
I got the multi meter out and recorded 5.2 volts on the led + / - terminals on the board and the same on the quick connector for the LED.
This is off freshly charged batteries listed above. 5.2 Volts seem quite a bit low to power a Lux V and this is with Lux V selected on the board.

[Jagahati]

Hmmm.


Check the voltage coming out of the battery pack. Sometimes the springs do not sit properly and give you a bad connection.

The US board should not be giving you an almost 3 volt voltage drop.

[Zook]

I had this problem as well BUT mine was working for a while (weeks) before it went dim.

I had another 2.5 and I checked all the components (voltages, resistance) and every pin on the board and found that one of them has a short to ground (what caused it I don't know unless it was heat). Unfortunately I haven't been able to find that part using the part number in my short searches.

I know the 2.5 has some heat issues with certain Vin and LEDs but 7.4 and a LuxV should be fine.

Mine was actually running on 6V (via regulator) on a P4.

I emailed Alex on this a week or so ago to warranty the board but haven't heard back yet. I may just contact novaconceptions instead. If they will not warranty it I will just find the component and repair it myself. its the toughest component to replace since you need a hot air station to do it (the connections are under the component).