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ArcticMyst Security by Avery

Invisible beam?

niiii

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Hello Ive just finished my first m140 build and I have a little problem. I cant see the beam at all... It looks so weak. I used S4 host, m140 diode and adjustable (1.6 - 2.3A) SL-SD-3 driver from survival lasers. Im not able to adjust the amperage to the exact value so I just set it to the half... so it should be 1.9-2A.
Im using single 18650 battery...

IMG_1172.jpg



EDIT: I figured out that I need atleast 6V for that driver... Single 18650 has 4.2V at full charge... It could be the problem. Or?...
 
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SN P

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Im not able to adjust the amperage to the exact value so I just set it to the half... so it should be 1.9-2A.

You'll need a test load to check and set the current of the driver. Ideally it shouldn't be more than 1.8A
 
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EDIT: I figured out that I need atleast 6V for that driver... Single 18650 has 4.2V at full charge... It could be the problem. Or?...

Kind of odd that no one else has answered your question yet, but it's not surprising seeing that the laser hobby is dulling down for a lot of people.

You are correct, the 6v minimum is your issue. You need 2 16340 batteries, or 2 18350 batteries to meet the 6v minimum requirement. With only an 18650 it will work, but output will be very low.
 

SN P

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You are correct, the 6v minimum is your issue. You need 2 16340 batteries, or 2 18350 batteries to meet the 6v minimum requirement. With only an 18650 it will work, but output will be very low.

I think the driver he is referring to is this if so then he may have read the info wrong. The description says its 6v Max rather than Min, and that it can be powered by 1 or 2 18650s and 16340s
 
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From Survival Laser's website:

The SL-SD-3 is an adjustable "buck" type diode driver. The SD-3 driver is sold in two output current ranges (approximately 400mA to 1.1A, and 1.6 to 2.3A at a maximum output voltage of 6 volts), and the current can be continuously adjusted by the user within these ranges. Lead wires are 1-5/8" long 26 AWG silicone insulated for flexibility and durability. Each assembly is tested before shipment. This driver is 16.8mm in diameter, fits the SL-PBR and SL-DPBR1 pill and brass ring and is designed to be powered by one (for diodes requiring less than 3.5V) or two 3.7 volt rechargeable RCR123A or 18650 batteries. Packaged in an anti-static bag.

designed to be powered by one (for diodes requiring less than 3.5V) or two 3.7 volt rechargeable RCR123A or 18650 batteries.

It's a diode requiring more than 3.5v. Therefor he needs 2 3.7v batteries.
 

SN P

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From Survival Laser's website:

The SL-SD-3 is an adjustable "buck" type diode driver. The SD-3 driver is sold in two output current ranges (approximately 400mA to 1.1A, and 1.6 to 2.3A at a maximum output voltage of 6 volts), and the current can be continuously adjusted by the user within these ranges. Lead wires are 1-5/8" long 26 AWG silicone insulated for flexibility and durability. Each assembly is tested before shipment. This driver is 16.8mm in diameter, fits the SL-PBR and SL-DPBR1 pill and brass ring and is designed to be powered by one (for diodes requiring less than 3.5V) or two 3.7 volt rechargeable RCR123A or 18650 batteries. Packaged in an anti-static bag.



It's a diode requiring more than 3.5v. Therefor he needs 2 3.7v batteries.

Didn't read that part :(.
I was under the impression that M140 diodes could be used with either 1 or 2 batteries?
 
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The M140 should be driven at no more than 1.8A, in an S4 that driver should be turned down all the way to 1.6A or it will over heat too fast. I have an M140 in a C6 and its driven at 1.5A and still heats up too fast. If driven at 2A it will kill the diode. Also two 16340 should be used or there is a battery extension tube available allowing for two 18650 batteries. Don't buy 18350 for that host unless you know what kind to buy because not all of them fit that host.

Alan
 

Garoq

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With some drivers, M140 diodes can be powered by one fully-charged 18650 battery in a sort of "low" mode that will produce around 150-300mW output.

The current of adjustable drivers should always be set using a test load and DMM or you risk killing the diode.
 

Garoq

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The M140 should be driven at no more than 1.8A, in an S4 that driver should be turned down all the way to 1.6A or it will over heat too fast. I have an M140 in a C6 and its driven at 1.5A and still heats up too fast. If driven at 2A it will kill the diode. Also two 16340 should be used or there is a battery extension tube available allowing for two 18650 batteries. Don't buy 18350 for that host unless you know what kind to buy because not all of them fit that host.

Alan

Alan, I have been using AW brand IMR 18350 batteries and they fit great in the S4/C6.
 

niiii

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I tried my 16340s and thats even more strange... When I use single 18650 its very weak but it works.. And when I use 2x 16340(Only 3V, dont have 3,7V 16340s) it just flashes and then turn off... Is this a battery problem? Or just voltage of the batteries?
 

SN P

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I tried my 16340s and thats even more strange... When I use single 18650 its very weak but it works.. And when I use 2x 16340(Only 3V, dont have 3,7V 16340s) it just flashes and then turn off... Is this a battery problem? Or just voltage of the batteries?

You need a test load to check and set the driver's current
 

Garoq

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I tried my 16340s and thats even more strange... When I use single 18650 its very weak but it works.. And when I use 2x 16340(Only 3V, dont have 3,7V 16340s) it just flashes and then turn off... Is this a battery problem? Or just voltage of the batteries?

Like Alan said you may have killed the diode with too much current. You can also check the batteries but the diode and driver should operate just fine at 6V.
 

niiii

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I dont think Ive killed the diode because when I use a single 18650 it works but weak... I think the 16340s could be the problem... They both were almost discharged...
 
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Does it ever flash brighter than the dim dot you normally experience? If it does, that's a good indication that your diode may still be fine, and that you just need to charge your batteries to determine if it is simply not enough supply voltage, or if the driver is broken.

Are you using 16340, or CR123a? CR123a you must always use brand new, matching cells. Never mix a new cell with a used one, in any chemistry, but especially for lithium non-rechargeables like the CR123a.

What 16340s do you have? Can you describe them or give us any text that may be on the wrapper?

Some buck drivers will simply go into direct drive mode if the load requires more voltage than the source(minus overhead). This will result in low output with a fully charged battery, and as the battery drains, the output drops until the diode can no longer lase at that voltage, and simply emits fairly monochromatic light, but not coherent.
 

niiii

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When I turn it on it just flashes, turn off, turn on and flashes... Im using rechargeable 16340, Pyra 880mAh.
 




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