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Apparently most lasers don't have polarity protection *SOLVED*

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So I put batteries in backwards on my 501B, pressed the button, realised my mistake, and when I put them in the right way I got a half second flash of blue and then nothing, and now when I screw the tailcap off I can see little sparks jumping from the threads to the cap, so I'm pretty sure its fried.

Which begs the question,
WHY THE F*** DOESN'T IT HAVE POLARITY PROTECTION????

Seriously, why would an expensive laser not have a simple safety measure that my 5$ ebay pens have??

I'm so pissed off right now I'm sorely tempted to chuck my lasers in a metal box and throw it in a river and be done with this hobby. Its becoming less fun and more money out of my wallet for nothing.
 
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Alex2893

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

your not the only one. actually most company and custom lasers dont have reverse polarity protection.
i have killed a bunch of lasers over the last year by putting the battery in backwards.
300mw spartan(thankyfully they replaced it for only the shipping cost)
tmack 501b 520nm. had to pay $130 to fix that
optotroics 175mw pen (they refused to replace it not even a small discount) Iv bought 4 pens from them and all died or broke in different ways. im still pissed about that.
about a $250 dollar loss.
i also just crushed my diode on my new tmack 1w 405nm by tightening the lens to much- $90 to fix it

Im extremely careful now which way i put the battery. half my lasers go one way and the other half the other way.

its a tough hobby. these lasers are so fragile and there so easy to break even in ways not thought possible
 
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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

So I put batteries in backwards on my 501B, pressed the button, realised my mistake, and when I put them in the right way I got a half second flash of blue and then nothing, and now when I screw the tailcap off I can see little sparks jumping from the threads to the cap, so I'm pretty sure its fried.

Which begs the question,
WHY THE F*** DOESN'T IT HAVE POLARITY PROTECTION????

Seriously, why would an expensive laser not have a simple safety measure that my 5$ ebay pens have??

I'm so pissed off right now I'm sorely tempted to chuck my lasers in a metal box and throw it in a river and be done with this hobby. Its becoming less fun and more money out of my wallet for nothing.
Hey Sorry for your loss, stay positive though! Use this mistake as a learning, also if you contact Eitan with the right attitude im sure he will Remedy your loss in some way that will keep You very happy, he has awesome customer service!
 

Alex2893

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

yes he does he answered all my question sometimes within minutes of me emailing him :)
 
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Rifter

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

For the price of sci-fi lasers im not surprised. You are getting a hell of a lot of laser for your money just not with all the bells and whistles.

This is why years ago with flashlights I started using a very fine tip permanent marker to mark the inside of the battry compartment with the polarity and I have continued this practice with my laser hobby.
 

Hap

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

That sucks Blarg.

If it makes you feel any better I once put the batteries backwards on my LaserGlow Anser(was tired & forgot the correct way they went). After realizing my mistake I was thinking about the guy with the Hercules & how he fried his and I was thinking "Damn, I broke it". Lucky for me it still worked (wtf)

Do what RYD said, contact him Im sure he will work something out. Accidents do happen bud :)

-Alex
 

crazyspaz

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Honestly, why would it? Think of it this way: if the masses of [cheaply] mass-produced chinese lasers don't have it, how do you expect lasers made by one person (as far as we know, one person) to have it? And I am pretty sure most of lazeerers drives don't have reverse polarity protection. The only drives I can think of that do are Dr. Lava's drivers.

I don't understand how so many people kill there lasers via reverse polarity...it isn't that hard of a concept to understand. If its that big of an issue, get a sharpie and put a "+" or "-" on the tailcap so you always remember.

oh also, I don't see anywhere that says "This laser has reverse polarity protection" on scifilasers.com.

I'm so pissed off right now I'm sorely tempted to chuck my lasers in a metal box and throw it in a river and be done with this hobby. Its becoming less fun and more money out of my wallet for nothing.
That money could have been saved if you would have paid a little more attention :/
 
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Eudaimonium

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Am I the only one that never, even once, inserted battery the wrong way in?

I am not kidding, I always got the battery polarity right.

Even if I forget the polarity for a specific laser, I remember it's diode and driver setup. If I can't remember that, just look into the battery barrel.

Or just look up the diode's specifics online.

I keep installing the reverse polarity protection in lasers I built, which saved a few lasers I sold to my friends later, but personally I never once got it wrong.
 
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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Every single laser I own besides the SF501B has reverse polarity protection. Even my ebay pens. So if a 5$ ebay pen has it, I don't think it would affect the cost significantly to put it in every laser.
 

Eudaimonium

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Every single laser I own besides the SF501B has reverse polarity protection. Even my ebay pens. So if a 5$ ebay pen has it, I don't think it would affect the cost significantly to put it in every laser.
You're right, it doesn't cost anything, and it's dead simple.

501B host is most disassembly-friendly.

So why don't you make it? Could be a fun little side project.

Oh BTW, $5 ebay pens don't actually have reverse polarity protection. The driver just so happens not to take any damage when batteries in wrong way. It's simple but robust.
 
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upaa27

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Am I the only one that never, even once, inserted battery the wrong way in?

I am not kidding, I always got the battery polarity right.

Even if I forget the polarity for a specific laser, I remember it's diode and driver setup. If I can't remember that, just look into the battery barrel.

Or just look up the diode's specifics online.

I keep installing the reverse polarity protection in lasers I built, which saved a few lasers I sold to my friends later, but personally I never once got it wrong.
Right here man. Never put in a battery wrong. I literally check the laser and batteries twice everytime I load it up.
 

mortuus

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

ah that sucks :( i have the same i will try remember this lol.
 
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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

You're right, it doesn't cost anything, and it's dead simple.

501B host is most disassembly-friendly.

So why don't you make it? Could be a fun little side project.

Oh BTW, $5 ebay pens don't actually have reverse polarity protection. The driver just so happens not to take any damage when batteries in wrong way. It's simple but robust.
Meh. I'll probably just take the diode/driver out of the host and put a new on from DTR in.. Maybe a nice 2 watt, might push the heatsink capability of the heatsink though.
 

KRNAZNBOY

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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Am I the only one that never, even once, inserted battery the wrong way in?

I am not kidding, I always got the battery polarity right.

Even if I forget the polarity for a specific laser, I remember it's diode and driver setup. If I can't remember that, just look into the battery barrel.

Or just look up the diode's specifics online.

I keep installing the reverse polarity protection in lasers I built, which saved a few lasers I sold to my friends later, but personally I never once got it wrong.
Yea, all my lasers have different setups, but i never have any problem knowing which way to put them in. The thing is, building your own laser gives you a better understanding of the electronics inside, giving you a better memory of how you wired your laser to work.

Another perk of building your own stuff, i guess... Never been into buying prebuilt stuff, simply because its so expensive...

Anyways, i have to agree, the reason most lasers don't have reverse polarity protection is because its so easy to prevent...

Sorry for your loss :(
-Matt
 
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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

Meh. I'll probably just take the diode/driver out of the host and put a new on from DTR in.. Maybe a nice 2 watt, might push the heatsink capability of the heatsink though.
The diode could be still good? i have no idea but maybe you might just need a driver
 
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Re: Apparently th Sci-Fi Lasers 501B doesn't have polarity protection

I don't know how many times I have burned
something up because I reversed the polarity. I
don't think I've ever put in batteries backwards, but
have done it many times with the red/black wires
coming out of my adjustable power supply.
 




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