NexGen, flicker, bins, etc.?

[wptski]

Going to make a gift of a light for a relative. I want a 1x123 configuration. I'm going to let him choose between a 5W BB750 I have and a 3W to be built.

I was thinking about a 3W NexGen 750. In the price and ordering thread a general statement is made that the NexGen is for Lux-III 1x123 or Li-Ions. Most Lux-IIIs are J/K bins. How can you use a 4.2V Li-Ion?

I understand the flickering problem can be reduced /stopped by using a lower 10 ohm Mc2ES, correct?

 

[Darell]

Re: NexxGen, flicker, bins, etc.?

The NexGen seems to be forgiving enough to work with a li-Ion. From what I've seen, the V is pulled down enough to actually operate it in regulation. Of course my Li-ions are showing a bit under 4V when I pull them off the charger. YMMV.

Some of the drivers can flicker, some don't seem to. Sometimes a lower resistance helps, sometimes it doesn't. Most folks are not being bothered by any flicker. I wish I could be more precise, but that's all I know...

 

[McGizmo]

Re: NexxGen, flicker, bins, etc.?

Bill,
From what I understand, there is an overhead or volltage drop within the circuit so on a fresh battery, even with a Vin above Vf of the LED, you are not in a real DD. Heck after the thread on "what is DD?", I am reluctant to comment! /ubbthreads/images/graemlins/blush.gif It is possible that you will see more than the 750 mA initially but I doubt you would see in excess of 1000 mA.

 

[wptski]

Re: NexxGen, flicker, bins, etc.?

Darell:

Thanks for the bit of a wishywashy answer! /ubbthreads/images/graemlins/grin.gif I just warn him that it may flicker and if he don't like it, choose the other one.

Don:

Thanks! I'll have to read the "DD" thread!

 

[Darell]

Re: NexxGen, flicker, bins, etc.?

Actually, your best bet is to NOT warm him about the flicker. Folks tend to see it more if they *want* to see it, if you know what I mean. /ubbthreads/images/graemlins/wink.gif

 

[wptski]

Re: NexxGen, flicker, bins, etc.?

[ QUOTE ]
Darell said:
Actually, your best bet is to NOT warm him about the flicker. Folks tend to see it more if they *want* to see it, if you know what I mean. /ubbthreads/images/graemlins/wink.gif

[/ QUOTE ]
Darell:

Good idea! I'll get to see first, we'll see if I even notice anything. It's my brother-in-law who saw my first light, an Arc4+ long time ago. A few weeks ago he saw my KL4 and later my PR-T 5W BB750! As a joke, he said that his B'day was next month and my sister says that he still jokes about.

He'll be in for a pleasent surprise! /ubbthreads/images/graemlins/grin.gif

 

[gorkon]

Re: NexxGen, flicker, bins, etc.?

What a nice gift. He'd better appreciate it - it's no run-of-the-mill flashlight!

 

[NewBie]

Re: NexxGen, flicker, bins, etc.?

I thought the NG only flickers when doing the resistor drop hack to get low level output?

 

[fleegs]

Re: NexxGen, flicker, bins, etc.?

Hello wptski.

I have a NG500 TXOJ that flickers with a 15 ohm resistor (I have tried two different 15 ohm resistors, flickers with both). The 10 ohm (now it may actually be flickering but it appears to be so fast that I can no longer see it) and the 22 ohm resistors do not cause this light to flicker. I have another NG500 TXOJ that does not flicker with any of the above resistors.

Hope this helps,
fleegs

edited to correct bin

 

[Darell]

Re: NexxGen, flicker, bins, etc.?

[ QUOTE ]
NewBie said:
I thought the NG only flickers when doing the resistor drop hack to get low level output?

[/ QUOTE ]
Yup. That's what we're talking about. In regulation, there are no flicker worries.

 

[wptski]

Re: NexxGen, flicker, bins, etc.?

[ QUOTE ]
Darell said:
[ QUOTE ]
NewBie said:
I thought the NG only flickers when doing the resistor drop hack to get low level output?

[/ QUOTE ]
Yup. That's what we're talking about. In regulation, there are no flicker worries.

[/ QUOTE ]
I didn't even understand correctly when it flickers! So, it's just when going high full output to low? That's not so bad! /ubbthreads/images/graemlins/grin.gif

 

[Darell]

Re: NexxGen, flicker, bins, etc.?

Some NG's have flickered when used on low. That's the "issue." When in regulation, they never flicker - when in low, we're dropping the voltage so low that the NG struggles to regain that regulation... and we won't let it. In that situation, they sometimes can flicker.

Flickering when changing levels is something that nobody really complains about - you're making and breaking contacts, so it won't always be smooth in the transition. It would be nice to always be "smooth" when holding a given level though.

 

[wptski]

Re: NexxGen, flicker, bins, etc.?

[ QUOTE ]
Darell said:
Some NG's have flickered when used on low. That's the "issue." When in regulation, they never flicker - when in low, we're dropping the voltage so low that the NG struggles to regain that regulation... and we won't let it. In that situation, they sometimes can flicker.

Flickering when changing levels is something that nobody really complains about - you're making and breaking contacts, so it won't always be smooth in the transition. It would be nice to always be "smooth" when holding a given level though.

[/ QUOTE ]
Darell:

Got it now! /ubbthreads/images/graemlins/happy14.gif