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ArcticMyst Security by Avery

Help find-best "cheap" led flashlight !

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2.5 amps from each battery IS safer... :thinking:
Either I made a mistake, or you misunderstood it.

Also, a while ago we were talking about AR coatings on both sides of a lens-turns out it does help total transmittance. Oops! There is a little bit of internal reflection between the outside of the lens and the air.

Interesting fact about the lenses... Never would have thought of that.

This one here:

Umm.... 5A is a problem no matter how many cells you use (in series), LOL...
 





Toke

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If you use a linear driver and need 5A it does not matter how many batteries you put in series. The 5A will flow from battery to battery to battery and there will still only be 5A coming out the end. The only thing that gets added up is the voltage, and with a linear driver excess voltage is wasted.
 
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This one here:

Sorry, I wasn't very clear-I mean that 10A from two batteries is not better than 5A from one battery. Also, remember how we were talking about if you accidentally turned the lens around the weak/more fragile side might point out? Yeah, I did that with my nitecore D10 yesterday. :oops:

If you use a linear driver and need 5A it does not matter how many batteries you put in series. The 5A will flow from battery to battery to battery and there will still only be 5A coming out the end. The only thing that gets added up is the voltage, and with a linear driver excess voltage is wasted.

But the current draw from each battery is halved... Yes, if a linear driver draws 5A at 4V, it will draw 5A at 8V. However, with two batteries that's only 2.5A apiece. Plus, I don't know of any flashlights that aren't complete crap that use a linear driver these days. The buck or boost drivers are so cheap, it's really not smart to use linear drivers.
 
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Toke

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Sorry, I wasn't very clear-I mean that 10A from two batteries is not better than 5A from one battery. Also, remember how we were talking about if you accidentally turned the lens around the weak/more fragile side might point out? Yeah, I did that with my nitecore D10 yesterday. :oops:



But the current draw from each battery is halved... Yes, if a linear driver draws 5A at 4V, it will draw 5A at 8V. However, with two batteries that's only 2.5A apiece. Plus, I don't know of any flashlights that aren't complete crap that use a linear driver these days. The buck or boost drivers are so cheap, it's really not smart to use linear drivers.

??? Ok, lets ignore the complications of drivers. Putting batteries in parallel will give you the voltage of one battery but let you add up the currents from the batteries. Putting batteries is series will add up the voltage, but not add up the current. Try think of it as if you get the current of the last battery in the line, the current(s) from the other(s) run into the battery in front of it and stay there. My pagebreak is out of order.
 
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??? Ok, lets ignore the complications of drivers. Putting batteries in parallel will give you the voltage of one battery but let you add up the currents from the batteries. Putting batteries is series will add up the voltage, but not add up the current. Try think of it as if you get the current of the last battery in the line, the current(s) from the other(s) run into the battery in front of it and stay there. My pagebreak is out of order.

Yes, lol, I agree with you-I must have misunderstood your last post.
 

Toke

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Well, I do not always express myself as clearly in English as I intend. :)
 
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Sorry, I wasn't very clear-I mean that 10A from two batteries is not better than 5A from one battery.

Also, remember how we were talking about if you accidentally turned the lens around the weak/more fragile side might point out? Yeah, I did that with my nitecore D10 yesterday. :oops:

Oh. Well we could have just avoided a long and confusing conversation there.
tongue.gif


How could you tell?
 
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Oh. Well we could have just avoided a long and confusing conversation there.
tongue.gif


How could you tell?

My bad... LOL. Well, now your knowledge is more resolute than ever! You're welcome! :na:

Also, I can't tell. That's the problem, LOL. I'm gonna try and figure it out once my XP-G arrives.
 
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is one side AR-coated? You should be able to tell if you take the lens out and look at how much it reflects. Shine a light on it and see how much light is reflected on the wall, then flip it over and do the same thing again.

I don't know which side the AR should face, though... the outside to keep internal reflections down? The inside to keep light from being reflected back onto the die? Seems to me like reflecting light back onto the die isn't a bad thing.... But then again, rarely are flashlights so exact.

As far as the amp draw thing, it's usually easier to have batteries in series so that you don't have to run wires from in between the batteries and from the tailcap. It just makes the system simpler, although if you did manage to wire them up in parallel you'd get twice the current handling.

I think toke's post clears it up the best:
batteries in series: voltage adds up, current same for all batteries.
batteries in parallel: current adds up, voltage is the same as one battery.

To add to that, you can think of current as the flow of electrons through a circuit. No matter how many batteries you have, that current has to flow through every device in the loop to make it around the circuit.
Voltage is I guess like how hard the electrons are being pushed. Batteries in parallel each "push" 4.2V, but in series one pushes 4.2V, and the next one pushes it 4.2V more.

I still think toke's was the easiest to understand, after going back and reading what I just typed....
 
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I don't know which side the AR should face, though... the outside to keep internal reflections down? The inside to keep light from being reflected back onto the die? Seems to me like reflecting light back onto the die isn't a bad thing.... But then again, rarely are flashlights so exact.

It goes on the inside. Not to protect the die, but so you can get maximum output. Light coming in from the outside isn't a problem as far as I know, but as ossumguywill just said, something happens with the inside of the lens and the air creates reflections.
 
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still waiting on my lightake 900 lumens p7 i ordered 2weeks ago...i hate waiting ...we need a u.s.based distributer right !!just alittle impatient.. has anyone bought anything from lightake yet??? if so how was your experience????
 
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Shining beam is based in the US and have plenty of good flashlights. Jedirock bought his MG P-Rocket from them a while back.

ShiningBeam.com Home Page

I'm most likely picking up an MG X-Thrower from them with the money I get for my 18th birthday.
 
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I agree Shiningbeam is great. Really good customer service and fast shipping.
 




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