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ArcticMyst Security by Avery

first portable laser build! :)

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just bought these 3 items from odicforce on ebay, bought a couple of things from jon before and all was in order so i think ill stick with him :)

this is what i ordered (by the way i just bought them this second so theyre not here)

hyperlinks:
laser host

driver board

laser diode


ive got a couple of questions about the connections for the driver and diode,

do i connect the diode pins to the indicated places in this pic:

connections.png


also should i connect -v (the one labeled LD- on the left) to the case and how would i do it?:)

thanks all!
 





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That driver is really made to have the diode soldered directly to it. The diode pin that's the case will solder to the side of the board that only has one pad. The other two pins will line up with the two pads on the other side of the board. The end of the board will be sandwiched between the pins.
 
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That driver is really made to have the diode soldered directly to it. The diode pin that's the case will solder to the side of the board that only has one pad. The other two pins will line up with the two pads on the other side of the board. The end of the board will be sandwiched between the pins.

so i should solder all the pins to the driver board? is it possible to do that and use the case aswell?

thanks
 
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all 3 pins should be soldered to the driver. the 'case' pin, that is, the one connected to the diode case, should be on the side of the board with only one tab. and the other two will be on the side that has two tabs.
 
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so if i solder all three diode legs to the right parts of the driver how would i link the case pin to the host?
 
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diode is pressed into to the heatsink. heatsink is pressed into the host.
 
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Looking at this I have a couple comments/concerns.
I think I'd tack the diode with jumpers or use clip leads to test before soldering it to the driver board after its been pressed into the housing & heatsink.
If a mistake is made, all 3 leads are soldered, and it doesnt work.... unsoldering 3 pins from a dual sided board can be tricky and puts a lot of heat in the diode.
Also, the case of the diode becomes common with V- when that pin is soldered. That makes the housing, heatsink and host body V- if my thinking is correct.
The diode + connection should be checked carefully to insure its not touching the diode case when it's slid in between the 3 pins and soldered. Leave a slight gap?
Both the driver and the host have springs which normally are V-. The pic has a spring many would see as V- on the V+ to the driver. Putting the battery in backwards will probably burn a trace or 2 (at a minimum) on the driver board till the short circuit is gone. My personal thought would be to use a 1/4" of copper wire...maybe from 12/2 electrical wiring as a + "nub" connection soldered to the driver board V+ and then let the host tail cap spring be the V- for the battery supply since the driver board is using V- and the diode - commonly.

If I'm not seeing this correctly, please correct me.
 
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ok thanks for the reply,

im not sure what the importance of the copper wire is and where exactly i should put it as ive not made a laser from scratch yet.

thanks
 
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It would be soldered to the driver board at the V+ pad instead of the spring. 1/4" would leave abt 1/8" sticking out past the edge of the PCB for the battery + to make contact.
That would eliminate remembering which spring is V-. At least to me.
Also, depending on how the host switch/tail cap is set up, it might be that its on all the time with a battery in if the heatsink(V-) isn't isolated from the host. It might be that the tail cap spring V- is isolated from the host body and the switch connects it to the body. If that's the case, you're in good shape.

Honestly, I'm not trying to confuse you. I'm putting myself in your place doing this build. I've had a tough health set back, so I'm doing a lot of reading, part gathering and such so I'll have what I need ready when I feel better.
 
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The spring is connected to the +ve on the driver so the -ve on the batt will go towards the tail cap. As the diode is -ve casing the contact from the -ve battery will be made thru the host to the heatsink to the dide casing then to the driver completing the circuit
 
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The V- is normally the spring. Having 2 springs just seems odd to me I guess. Especially when one is the V+.
 
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The V- is normally the spring. Having 2 springs just seems odd to me I guess. Especially when one is the V+.

Your thinking about green's. IR diodes are case+. Red's are case-. 445's and 405's don't use the case as a diode connection so they can be either depending on what driver you use.

In his build with a red diode. The body of the host will be ve-. The ve+ will go to the spring on the driver.

Not really sure where your getting this second spring from.. the driver only has one attached. which is the one that matters. the one in the tailcap is just connected to the host with a switch.
 
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I looked at the host link, yes.....there is a spring there too.
The second spring is the one already mounted in the tail cap. I'm use to springs being V-, flashlights, battery holders, radios basically 99% of the stuff I've seen.

"Not really sure where your getting this second spring from.. the driver only has one attached. which is the one that matters. the one in the tailcap is just connected to the host with a switch.
I understand that, but since it's the V- connection...well...it matters to me.

qumefox, you know I'm new to lasers and as you described a V+ host may be needed/found due to some diodes configuration. Unless the heatsink is isolated. Yes, my greens are host V+ as are the 405's of the same brand, but the spring is still on the V- end of the power source. In my readings I've found similar differences in drivers too. Some vary the +, some the -.

I figure I'll own many lasers over time. Having one with 2 springs and the really nice gold spring that comes with that driver, after time not used I would probably toss the - towards it. Having one spring, in what appears to be an industry standard, seems much simpler to me.

Matt, I think you are doing great. I apologize if i confused you with the spring issue.
 
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There's not anything to get confused about with this particular one though. That driver is clearly labeled as far as what goes where. +ve goes to the battery end of the driver. -ve goes to the driver via the diode case, which happens to, in a red diode, do double duty as the LD- as well.

It was your comment that the spring was usually -ve that can cause a LOT of problems for someone not paying attention. The only lasers that would be 'usually' true for would be IR's or greens, but if the diode is isolated, it might not be true even then. 405/445 have isolated diodes anyway, they don't use the case pin. These lasers can be either or.
 
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ok thanks for sorting it all out for me :p

so, ill solder all the pins to the driver, get it all inside the host and put the batteries in -v first :)

just hoping odicforce sends me the bits soon :) took 5 days to get them posted then 2 for delivery last time :'(


thanks for all the info :)
 




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