Troubleshooting 301 Ebay (3v vs 3.7v)

[nibbles]

I realize it's cheap crap, but I wonder if 3v is too low to even power on versus the "normal" 3.7v? The cr123 I could find is only 3...

Just curious!

Got a surprisingly speedy delivery of a 301 Laser model from Ebay. Did not come with 18650 battery, which I realized and then purchased 2 day shipping for a pair from Amazon.

In haste to see if it worked at all, I bought (then returned) a cr123 3v from the local drugstore. There was nothing close to an 18650/rcr123 in local stores near me.

So the thing didn't start at all, tried both orientations of battery as well.

 

[Teej]

I realize it's cheap crap, but I wonder if 3v is too low to even power on versus the "normal" 3.7v? The cr123 I could find is only 3...

Just curious!

Got a surprisingly speedy delivery of a 301 Laser model from Ebay. Did not come with 18650 battery, which I realized and then purchased 2 day shipping for a pair from Amazon.

In haste to see if it worked at all, I bought (then returned) a cr123 3v from the local drugstore. There was nothing close to an 18650/rcr123 in local stores near me.

So the thing didn't start at all, tried both orientations of battery as well.

An 18650 is quite a bit larger than an RCR123 (Which would be a 16340)...

...and, if the first time you tried to insert them you reversed the polarity...even if right the second time, the thing might be toast already and you were done.

If it was SUPPOSED to use ONE 18650 (About as long as TWO 16340/RCR123), that's 3.7 v.

If you used TWO CR123 (3.0 v each), that's 6 v, possibly blowing the board, etc....especially if reversed, etc.

If meant for an 18650, a CR123 might not even contact the poles...and/or might not have the juice to activate it. (A potentially better option, as it might NOT be toast, etc)

Can you describe what you did, step by step, after describing the size of the cell holder part?

 

[nibbles]

Hi, I didn't double up. I took the spacer out to see if o could get a power up from one 3v cr123. Put negative side facing up to contact the spring coming from the diode, positive side down.

 

[Teej]

Hi, I didn't double up. I took the spacer out to see if o could get a power up from one 3v cr123. Put negative side facing up to contact the spring coming from the diode, positive side down.

You tried it both ways...which did you try first? (At 3 v, you might get lucky?)


Add what wavelength and if you know the diode...some go like a flashlight, some go in the opposite of positive towards output end.


Hopefully, what did the laser's INSTRUCTIONS say about insertion/polarity?


PS - Now that I think about it...the ebay 18650....please (PLEASE!) tell me the brand doesn't end in "____fire"

 

[nibbles]

405nm I only tried negative side up towards the diode same as instruction stated. Although if it's designed for 3.7 then maybe just too low voltage? I returned the cr123... Only tried it in the store

 

[Teej]

405nm I only tried negative side up towards the diode same as instruction stated.

Although if it's designed for 3.7 then maybe just too low voltage? I returned the cr123... Only tried it in the store

So the thing didn't start at all, tried both orientations of battery as well.

???????

 

[nibbles]

Sorry bad english!

I meant I only tried it the instructed way at first, both new batteries. I tried once the opposite way quickly but did not want to fool around with it and make it worse. Since I returned them immediately I can't try more.

I should receive the 18650's today in the mail. I have access to a multimeter, although it may not be working with all modes at this point, I think it can't read mA anymore...

Is it worth diagnosing if the new 18650's don't work? It looks like the module is glued into the casing. Also, I took the "focusing lens" housing off by unscrewing, only to find there was no lens in it at all. It definitely looks like they at least lied about that...the seller did respond with some basic troubleshooting questions in bad English, clearly from China.

 

[nibbles]

It ended up being that the positive side of the battery for 18650 touches the spring...it worked...

This is against every electronic device I've ever used and doesn't really make sense...the spring is always for the flat side of battery/negative....but in this pointer it only works with opposite.

 

[Teej]

It ended up being that the positive side of the battery for 18650 touches the spring...it worked...

This is against every electronic device I've ever used and doesn't really make sense...the spring is always for the flat side of battery/negative....but in this pointer it only works with opposite.

A lot of lasers work the opposite of flashlights, etc, in that way.

Its really dependent on the specific setup.

I have a 3 watt 445 nm (Blue) for example that when it had a round diode, needed the cells to be inserted with the NEGATIVE to the diode/positive to the tail switch.

When the round diode was replaced by a square diode, THAT meant the cells now went the OTHER way (What we consider, typically, to be normal).

I have a 532 nm (green) that's "positive to the tail" oriented as well...and so forth.

I do mental gymnastics EVERY time I change cells because I am paranoid that I'll Lex-Out and put them in the wrong way and blow the laser.

I had some flashlights with the same host, and, THEIR cell needs were also different...especially some with one 18650 and others with TWO 18350, and, As they all LOOK the same, one day I forgot which was in my hand, and put 2 into a light that could only handle 1 (Instant death of light).

Some have reverse polarity protection, etc...a life saver if dyslexic, etc.

:can:

 

[nibbles]

Yeah it make no sense, especially since the batteries have almost no contact surface on the "button" side. Why would you use that side for the spring instead of a flat surface. The host has a key in that end cap and the cap inside has a contact plate that is perfect for the flat side...who knows.

Although I think some 18650's have no button side? Maybe that is why

 

[Teej]

Yeah it make no sense, especially since the batteries have almost no contact surface on the "button" side. Why would you use that side for the spring instead of a flat surface. The host has a key in that end cap and the cap inside has a contact plate that is perfect for the flat side...who knows.

Although I think some 18650's have no button side? Maybe that is why

I think its more related to which way the electrons need to flow...through the diode circuits.

 

[nibbles]

Quick Question. In your opinion. This lens seems to focus "out" to the point of making the dot about 2 feet wide or more from maybe 10 ft from a wall. Is that relatively safe to look at more extensively then a focused beam?

Just curious, it's almost more like a blacklight bulb when so out of focus.

 

[Pman]

Focused like that means the actual focal point is very close to the lens which means that if you try and light a match with it you might ruin the lens. I wouldn't try to make anything smoke near the lens unless it is at least a few inches away. The little embers from a match lighting can potentially hit the lens and you will not be able to clean it. You get something on a plastic lens it is pretty much ruined.
Yes, it is safer to look at than a focused point. Shouldn't look right at ANY laser beam though. Eyeballs are currently irreplaceable.