Weird issue on a cheap 5mW pointer.

Hello.

I have purchased a cheap 5 mW green pen on Ebay and it has been performing fine the first 2 days. After 2 days it suddenly began to dim randomly. Now it shines fine after several shots and only if I turn the pen about 90º while holding the start button pushed. The Beam becomes sooooo dimmed when I point the pen upwards, towards the zenith or if I point the pen directly to the floor but it suddenly become bright if I shake the pointer up-down, etc.

I have checked batteries, replaced them, but no change.

I have searched on the forum but all "dimming" problems are regardless to shaking the pen according to the old threads related to this issue that I have found.

Any thought about this problem?

Thx.

Loose crystals,component shorting out on the driver(touching the inside wall of the host) weak spring, dirty contacts.... etc.


I had to expand the spring on my ebay bluray to make it put more pressure on the batteries for a better connection and it sounds like the same thing is happening to you. If you shake it do you hear the batteries moving around alot?

Could you post the link to the listing?

I had one of those really cheap pointers, the middle had no threads, the halves just pushed together.

It did the same thing, poor battery contact, I gave it away.

Here you go: 5mW Green High Power BEAM Laser Point Pointer Pen 6013 en venta en eBay.es (finaliza el 24-mar-10 04:55:58 H.Esp)

The pen is insanely cheap and it has been running great for 2 days. Beam was great and I could see the point 2-3 kms far away. But last night I carried it on my pocket for about 5 hours. Later it began to run weird.

I am trying to disassemble the head to check cristal but I can't pull the head out.

This pen has got threads on the middle and it seems to be strong and well built.

Dont disassemble it!!!!!!!

Try to expand the spring to make better contact with the batteries i am almost positive that will fix it.

I have checked for weak batteries connection and it doesn't seem to be the problem.

Since it began to dim I can see something like a "stars cluster" around the point. I couldn't see such pattern when it performed fine.

I am testing it again and again and it is weird how the beam turns brighter when I shake the pointer or when I just turn the pointer few degrees on its axis.

I've had a problem with these pointers dimming in the past. Just spoke to another person in a recent post who had the same trouble.

From what I've found, it *is* a contact/connection issue, and this has solved it for four of them in my case and one of them for another person:

-Where the two halves screw together, the thread there is painted with a supposedly conductive silver paint. This connection doesn't work well and is usualy problematic. Unscrew the two halves and lightly (VERY LIGHTLY) sand the threads with a fine grain sandpaper, just enough to uncover the brass underneath.

-Also lightly sand the brass spring protruding from the inside of the upper half. You can use some DeOxit here too if you have it, as oxidization seems to be a problem on this brass spring.

Try both of those; I had one that even ran pulsed and dim until I did this. The directional issue likely has to do with weight placed on one half of the pointer case, interacting with this screw together joint in a strange way. The conductivity between the two halves is generally very intermittent. Sanding off some of that paint (and the roughening of it making a more solid connection) seems to get rid of this problem.

Hello,
I have tried to sand the threads but nothing has changed. It seems that problem is located on the head of the pen. When I point the laser on the floor the dot gets very dim and almost dissapears. It is necessary just a little shake in the head and the dot becomes brighter. If I stop shaking the dot gets dimmer again.

From what you have described, the pointer has an issue with gravity... only use it in space. LOL

Seriously, my thoughts are that the contact spring at the head of the laser is too compressed, and the weight of the batteries makes it that the + contact at the bottom of the battery well barely makes contact when in the upright position.

Try pulling and extending the spring at the laser head, this will provide more pressure on the batteries so that they will make proper contact at both ends. If all else fails, drop a washer or two at the bottom of the battery well... this will raise the batteries by a few mm and maybe improve contact.

- Robert