Simple XPH-70 and Qlite driver doesn't work.

Flashlight Modding and DIY Parts
1

Hello everyone

I’ve purchased a few cheap lights but wanted something slightly better so I got myself a Convoy X3 host, XHP-70 on 6v Sinkpad and Qlite driver with the intention of adding some 7135’s later on.

I cannot get the bloomin thing working, I’ve soldered plenty of thing’s before but nothing that small. I made an attempt to solder some slightly thicker wires onto the driver, the positive wire went on okay but with the negative I struggled to see much of a solder pad on the board after desoldering the original wire. I attached the new wire but it didn’t look pretty. haha

Fitted it all together after soldering the wires to the emitter, battery connected but it doesn’t work. No burning smell or anything and the unprotected 18650 is fully charged, I’ve also checked the switch with a multi meter.

So to rule out any problems I decided to desolder the wires on the emitter, use a new Qlite driver and leave the wires that come with it that should be soldered on correctly still in place, locate it in the flashlight, feed the wires through and solder them to the easily visible large pads on the sinkpad. Yet it still doesn’t work!

The only thing I can think of is the polarity of the XHP-70 , it came already flowed onto a 6v sinkpad and I cannot see any polarity markings on it, it just crossed my mind that it may have been flowed on with reverse polarity.

Is there anything obvious I’m missing?

Thanks
Andrew

2

Unfortunately I think it’s something very obvious. It’s a 6v emitter, it won’t work on a single 4.2v 18650 without a boost driver. Normally we use 2 cells to power an XHP, and that would require zener-modding your Qlite.

3

This

4

Basically know you are using a linear driver to power a 6V LED from a 3.7V nominal source (single 18650, fully charged at 4.2V) , it cannot work.

5

Ahh!

I assumed that 6v was the max working voltage and it would work okay with a single 18650 but with reduced output, now I know.

Thanks very much, I’ll look into the zener modding of the driver. :wink:

6

Yep as the others said, you will need to mod your Q-Lite with the zener mod & use two 18650’s in series to drive the 6v XHP70.

7

Yes, Andrew, Zener modding it will allow the driver to work but you will also need a light that can take two 18650 in series. If it can only take a single 18650 then you will have to use two 18350 cells in it to supply the needed voltage.

8

If you’re not used to soldering smd components, you’re going to find stacking extra 7135s on a Qlite driver a real ball ache.

A trick I used was to temporarily remove the spring and used an minute drop of superglue to stack the 7135s before soldering the bridges between the pins.

The diode that is on the board has to be replaced with a 200ohm resistor (I used a 220ohm 0805 smd resistor) and a 4.3V zener soldered in parallel with the capacitor on the other side of the board. The cathode (striped side) end points towards the centre of the Qlite.

MTN Electronics sell one ready to go that’d suit a XHP70 (with 2 batteries) http://www.international.mtnelectronics.com/index.php?route=product/product&path=67_116&product_id=53

9

I’ve been looking for an extension tube for the Convoy X3 but couldn’t find anything, I’ll do some more searching and have a think about what I can do.

Thanks :slight_smile:

Excellent, thanks for the tips. :expressionless: I’ve seen plenty of photo’s on here but it’s not until you see a driver yourself then you realise how small everything is.

I might give it ago myself as I should be able to get the components in a few day’s, I’ll have a little practice on something first