Hi, all - I bought this flashlight from DealExtreme. It's a good-looking and very solid flashlight, but I've had an issue with it flickering when bumped. I'm reasonably sure that this is not due to the driver or the LEDs themselves, but due to the case and the way it contacts the "plate", as I'll demonstrate below.
So, when I'm running it and I give it a solid tap, the light level changes. Left to its own devices, it'll do this after about half an hour whether or not I tap on it, without getting very hot. It's not some sort of overheating protection, and I doubt the flashlight is that smart anyway.
How do I know it's the case? Well, here's a photo of the driver:
I attached the positive side charger directly to the red wire's solder junction and the negative side to the outer copper ring. Yes, I know it's bad, but I didn't have a 3.7v power supply, and the charger was 4.2v. Aside from a 60hz flicker, the brightness didn't change. This indicates to me that there is a bad connection between the base/batteries and the board itself. But where? Here's a photo of that setup:
What does this mean? Perhaps there is a bad connection between the base and the batteries? I checked this and went ALL over it with a multimeter. The connection is good from the positive end of the battery to the ring of the case, which connects to the outer copper ring of the driver. Also, it came missing a case screw, so I scraped the insulation off a spare and used it instead, in case you're wondering why one screw is black. Here's that:
And the black screw:
The base's connections are all solid, I went over it with a multimeter from spring to battery to edge and every which way. It's a big solid piece of aluminum! So that leaves only TWO places which might be the culprit - the connection between the edge of the battery case and the driver, OR the actual connection from the positive ends of the battery to the driver. I wondered whether or not the board was just too far from the batteries. Thus, I created an extremely precise and exact spacer to elevate the driver just slightly off the head, toward the case, toward the batteries in hopes of making a solid connection. Here's my extremely precise piece of aerospace technology:
And still it flickered. This has left me out of ideas. Maybe there's some coating on the driver? I cleaned it with alcohol but there still seems to possibly be some varnish. Why can't I get a steady beam out of this flashlight for more than a few minutes? The fact that the flickering gets worse after a few minutes makes me think it's possibly thermally related, but why doesn't it get hot then?
I'm thinking I just got a bad light and it's wisest to return it, but I don't really want to wait another two months for shipping.
Also, these batteries take forever to charge and running them for just a few minutes seems to take them down quite a bit. I'll measure it with a multimeter later.
Thanks for reading all!
So, when I'm running it and I give it a solid tap, the light level changes. Left to its own devices, it'll do this after about half an hour whether or not I tap on it, without getting very hot. It's not some sort of overheating protection, and I doubt the flashlight is that smart anyway.
How do I know it's the case? Well, here's a photo of the driver:
I attached the positive side charger directly to the red wire's solder junction and the negative side to the outer copper ring. Yes, I know it's bad, but I didn't have a 3.7v power supply, and the charger was 4.2v. Aside from a 60hz flicker, the brightness didn't change. This indicates to me that there is a bad connection between the base/batteries and the board itself. But where? Here's a photo of that setup:
What does this mean? Perhaps there is a bad connection between the base and the batteries? I checked this and went ALL over it with a multimeter. The connection is good from the positive end of the battery to the ring of the case, which connects to the outer copper ring of the driver. Also, it came missing a case screw, so I scraped the insulation off a spare and used it instead, in case you're wondering why one screw is black. Here's that:
And the black screw:
The base's connections are all solid, I went over it with a multimeter from spring to battery to edge and every which way. It's a big solid piece of aluminum! So that leaves only TWO places which might be the culprit - the connection between the edge of the battery case and the driver, OR the actual connection from the positive ends of the battery to the driver. I wondered whether or not the board was just too far from the batteries. Thus, I created an extremely precise and exact spacer to elevate the driver just slightly off the head, toward the case, toward the batteries in hopes of making a solid connection. Here's my extremely precise piece of aerospace technology:
And still it flickered. This has left me out of ideas. Maybe there's some coating on the driver? I cleaned it with alcohol but there still seems to possibly be some varnish. Why can't I get a steady beam out of this flashlight for more than a few minutes? The fact that the flickering gets worse after a few minutes makes me think it's possibly thermally related, but why doesn't it get hot then?
I'm thinking I just got a bad light and it's wisest to return it, but I don't really want to wait another two months for shipping.
Also, these batteries take forever to charge and running them for just a few minutes seems to take them down quite a bit. I'll measure it with a multimeter later.
Thanks for reading all!
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