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ArcticMyst Security by Avery

SOLD: 4.2W NDB7A75 445nm handheld With G7






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Re: FS: 6W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

But what if he can and with higher mAh in a given size produced less voltage drop, even two tenths makes a considerable difference with the jetlasers unit, I verified that.

Forgive my MAH, I know better, wrote that 5 min after waking, now I have coffee in hand but posting with a smart pjone.
 
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rhd

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Re: FS: 6W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

But what if he can and with higher mAh in a given size produced less voltage drop, even two tenths makes a considerable difference with the jetlasers unit, I verified that.

No, it would not make a difference where two cells are used in series to drive a buck that is stepping down the voltage substantially. If it's stepping down to 5V, it shouldn't matter whether the voltage going into the driver is 8.4V, or 7.8V, or 7.2V, etc.
 

Jstr

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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

^yeah battery voltage sag shouldn't matter in this case, but the type of battery definitely does. For one of my lasers, I was getting 1.8 W with 2 mediocre 16340s and then 2 efest IMR 18350s bumped me up to a 2 W peak.
 

rhd

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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

^yeah battery voltage sag shouldn't matter in this case, but the type of battery definitely does. For one of my lasers, I was getting 1.8 W with 2 mediocre 16340s and then 2 efest IMR 18350s bumped me up to a 2 W peak.

The difference there was that mediocre 16340s may have had an insufficient C rate. Sanyos do not.
 
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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

My observation is that at 4.0VDC or lower my Jetlasers won't put out 1.1 watts, but when running on an external supply at 4.2 volts it will and that none of my batteries no matter who makes them or whether rated for high current or not will stay at 4.2 VDC, they all drop down two to three tenths in a very short matter of time.

The Jetlasers has a linear constant current regulator in it and needs full voltage to put out full power, aside from needing to be at the right temperature too, if chilly it will put out half power. I'm just reporting Pogo was right about the power being lower if the temperature isn't right as well as battery, regardless of mAh capacity or current capability, if the voltage drops down a few tenths right away I won't have full power out with this particular laser.

Having strayed a bit, let me add what a beautiful laser you are selling, I love the way that one head was machined to reflect some of the laser light at the tip from the beam, nice.
 
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Podo

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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

Push up
 
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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star


I've never owned a laser as powerful as yours so my questions may be stupid.

What metal were you cutting? (How come it can cut it but not burn your fingers?!)

Did you damage your room shining it around?

The different power levels: eg safety level of <30mW; I presume this is PWM? (as I doubt the diode would output that low) How have you assured it is actually safe, i.e. how long is it on for (as 6W even for a very tiny period seems dangerous)

Thanks!
Chris.
 

Podo

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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

1.What metal were you cutting? (How come it can cut it but not burn your fingers?!)

It was just 4x0.8mm soldering wire twisted together, tin if you ask what was the specific metal.



2.Did you damage your room shining it around?

No if you never leave it running on the same place with G1/2/9 but not including G7 or 3 elements situation. Never forget the divergence over distance is big for 7A75 no matter which lenses you are using so it basically the same burning power of a 2W blue in a long distance and even worse.


3.The different power levels: eg safety level of <30mW; I presume this is PWM? (as I doubt the diode would output that low) How have you assured it is actually safe, i.e. how long is it on for (as 6W even for a very tiny period seems dangerous)

I tested it simply . My power meters didn't even respond with no output readings at all but for safety reason I gonna labelling it <30mw.


Thanks For looking!
 
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Re: FS: 5W NDB7A75 445nm handheld With G2+G7 - the Sliver Star

On the safety side, our hobby is one which requires safe practices, no doubt about it, more so the higher power you go.
 
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Podo

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Re: FS: 5.4W NDB7A75 445nm handheld With G2+G7 - the Sliver Star price lowered!

Price lowered to $505.5 still including shipping & fees.
 
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Podo

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Re: FS: 5.4W NDB7A75 445nm handheld With G2+G7 - the Sliver Star price lowered!

Feel free to pm me. The price won't drop any further but for only once as sanwu sold 10+ units already each for $450 roughly without including any traditional fees.
 

rhd

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Feel free to pm me. The price won't drop any further but for only once as sanwu sold 10+ units already each for $450 roughly without including any traditional fees.

Wait - you're saying that you've been off selling these in other venues for $450 each (and have sold 10+ so far at that price elsewhere), meanwhile you've been offering them to LPF members for between $500 and $550 ???
 
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Podo

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Re: FS: 5.4W NDB7A75 445nm handheld With G2+G7 - the Sliver Star price lowered!

Wait - you're saying that you've been off selling these in other venues for $450 each (and have sold 10+ so far at that price elsewhere), meanwhile you've been offering them to LPF members for between $500 and $550 ???

My price are including shipping and paypal fees...which take them out of my current price then it would equals to $450 :thinking:
 

rhd

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My price are including shipping and paypal fees...which take them out of my current price then it would equals to $450 :thinking:

Fees equal 3%, so on $550, you were receiving $533.50 and on $500 you were receiving $485. We all know that shipping from China is very inexpensive. So it sure seems like you must have been selling elsewhere for less than you are, or at least were initially trying to get from LPF members.

There's no rule against that, but it seems sketchy to me. Most sellers offer a better price to members of our community, not try to capitalize on them.
 
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Podo

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Re: FS: 5.4W NDB7A75 445nm handheld With G2+G7 - the Sliver Star price lowered!

Fees equal 3%, so on $550, you were receiving $533.50 and on $500 you were receiving $485. We all know that shipping from China is very inexpensive. So it sure seems like you must have been selling elsewhere for less than you are, or at least were initially trying to get from LPF members.

There's no rule against that, but it seems sketchy to me. Most sellers offer a better price to members of our community, not try to capitalize on them.

Inexpensive?? The last time I sold my jetlasers handheld to alaskan I paid a good $55 to ship as fedex economy.
 
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