Resistance in switch issue

[Vetttech]

So, i am down in my basement, or as i like to call it, my laser playground, and i am playing around with a 200mw 303 650nm unit that i just received yesterday and i notice the beam dot is fading from bright to dim to bright! Bad battery?Nope! Bad driver? Nope! Bad diode? Nope!

It turns out the switch is just making enough contact to power on, but not at full power! In other words, it has some resistance in the switch! Could be dirty contacts or just a cheap crap switch.

Just a cautionary story! If your LPM is showing up and down numbers, this may be the problem! :scowl:

This is what you get with cheap lasers!!! :cryyy:

 

[BobMc]

Glad you figured it out. Like the idea of your "laser playground", we should all have one. :gj:

 

[diachi]

So, i am down in my basement, or as i like to all it, my laser playground, and i am playing around with a 200mw 303 650nm unit that i just received yesterday and i notice the beam dot is fading from bright to dim to bright! Bad battery?Nope! Bad driver? Nope! Bad diode? Nope!

It turns out the switch is just making enough contact to power on, but not at full power! In other words, it has some resistance in the switch! Could be dirty contacts or just a cheap crap switch.

Just a cautionary story! If your LPM is showing up and down numbers, this may be the problem! :scowl:

This is what you get with cheap lasers!!! :cryyy:

Seen those switches cause issues before, usually just cheap micro switches - sometimes not even properly rated to handle the current requirements of the laser.

 

[Vetttech]

Seen those switches cause issues before, usually just cheap micro switches - sometimes not even properly rated to handle the current requirements of the laser.

The little 303 lasers would be great if they would get rid of the micro switch and the lock and key tail cap and just go with a click on-click off tail cap!

Except for the micro switch, i like the 303 units!

 

[diachi]

The little 303 lasers would be great if they would get rid of the micro switch and the lock and key tail cap and just go with a click on-click off tail cap!

Except for the micro switch, i like the 303 units!

Agreed, I much prefer the tail clicky too. At the least a nicer side momentary push would be nice, but for $8 we can't really complain!

If you want a small 532nm with a tail clicky look at the JD 850 pointers, they're the same (or at least almost the same) as the old Romisen 30mW pointers and seem to do about the same power. I got mine from Gearbest but I've seen them other places. Cheaper than the 301 when I bought mine, but typically lower power too.

 

[GSS]

Sometimes the 301's 303's switches or momentary buttons aren't supported to well and will bend the driver as they are attached to them. Something to consider..

 

[Vetttech]

Sometimes the 301's 303's switches or momentary buttons aren't supported to well and will bend the driver as they are attached to them. Something to consider..

Yep! I have seen that happen also! The driver board gets pushed in and bent and the micro switch becomes almost useless. Just order a new one and wait for another month for it to arrive! The LIFE of a laser collector! Good times!!

 

[paul1598419]

Yeah, these Chinese switches have been causing problems for awhile now. Any time someone has an intermittent problem it is one of the possibilities I propose.

 

[Benm]

Yup, and it is really annoying.

The put pushbuttons in lasers that are rated for something like 100 mA while the actual current is 10 times that. This often works for a while but will degrade (or even burn out) the contact points over time. It's really annoying because it's hard to find this failure mode until you use a multimeter to see the voltage behind the switch.

I've had some problems powering up 445s from 2 3.7 volts batteries and that had me puzzeled for quite a bit as there seemed to be plenty of margin for voltage drop. I connected it up quickly using some thin croc clip wires and those dropped so much voltage due to thin conductors and bad contacts that the driver could not retain regulation despite having 2 volts or so to spare on paper

 

[Vetttech]

Agreed, I much prefer the tail clicky too. At the least a nicer side momentary push would be nice, but for $8 we can't really complain!

If you want a small 532nm with a tail clicky look at the JD 850 pointers, they're the same (or at least almost the same) as the old Romisen 30mW pointers and seem to do about the same power. I got mine from Gearbest but I've seen them other places. Cheaper than the 301 when I bought mine, but typically lower power too.

Thanks for the heads up on the JD 850's! Got Red and Green on the way! I wonder if the JD 850 tail cap will fit on the 303 host?

 

[diachi]

Thanks for the heads up on the JD 850's! Got Red and Green on the way! I wonder if the JD 850 tail cap will fit on the 303 host?

Awesome! I've been enjoying my little 532 so far, haven't tried the reds. Let us know how you get on!

Tailcap is smaller so it won't fit, the whole laser is quite a bit smaller. They use a single 16340. I much prefer it for any time I'm taking a little pointer somewhere.

The other advantage of the clicky I've found is that it's much harder to accidentally press the button, I've had that issue with side momentary switches like on the 301/303 before.

 

[Vetttech]

Awesome! I've been enjoying my little 532 so far, haven't tried the reds. Let us know how you get on!

Tailcap is smaller so it won't fit, the whole laser is quite a bit smaller. They use a single 16340. I much prefer it for any time I'm taking a little pointer somewhere.

The other advantage of the clicky I've found is that it's much harder to accidentally press the button, I've had that issue with side momentary switches like on the 301/303 before.

OUTSTANDING! I can not wait to get them! I like small with a bit of punch! :yh: