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how far can i push a phr803?

yeah, you're right, if there's a visible beam he probably has plenty of power out - because seeing the beam can be difficult with 405nm without fog or smoke, unless it's really dark. So maybe all he needs to do is screw the focus out more to get burning; and seat the diode to be able to focus far away for a pointer.

quick edit: you posted above justas I got this one out; will think about what you wrote a bit....


 :-)
DanQ
 





ok... can you flip the lens, so the screwdriver slot is on the inside toward the LD? that should put the actual lens closer... the focus may be waay too far though, so start checking results before getting it too far screwed in.
 
just tried it, smallest i can get it is about the size of a quarter at like 15 feet away
 
Mohrenberg said:
the only to way to explain the focusing thing.... (and this is for me trying to focus it for long distance shining)

pretend that the lens is screwed out really far.....you'd have a huge dot, as you screw it in the dot will get smaller and smaller, and if you keep going it will get to it's smallest, then start to get big again as you keep screwing it in, well on mine it never gets to it's smallest when i have that little silver ring on the end of the lens.
if i remove the silver ring to screw it in more, the smallest i can get it before it starts to get bigger again is around 1 foot wide at around 50 yards away (very rough estimate)
Click to expand...


I believe that this is simply a combination of an optical illusion AND the significant amount of scattering that 405nm light is subject to.  Are you alone?  It is easier with a friend to help.  Anyway, here's what you do.  Focus the beam to it's smallest size(at the 50 yard mark you are using now) and leave the focus set at that point.  Now, either lock the button down or have someone else push the button for you.  You want to be down at the other end of the 50 yards with the light on.  Be very careful about getting the light in your eyes.  Goggles would be helpful here.  When you are down at the 50 yard mark, looking at the "dot", how big is it?  Is there a central small dot with a larger "halo" around it?

If you have a friend with you, you can have them actually focus the light as you watch.

If it will focus well enough up close to light a match, then the lens is fine.  If you can see the dot get smaller and then start getting bigger again, the lens can focus to the point of convergence.  Now it is simply a matter of learning about what the 405nm light actually looks like in the field and "educating" your eye to 405nm light's idiosyncrasies. It will NEVER look like a red or a green laser dot.

Peace,
dave
 
if it isn't an illusion,
maybe there's something (like a fouled thread) preventing the lens from being completely screwed in?

(I can see the warning sticker:
"WARNING! if resistance is encountered, do not attempt to screw in lens" ;-)
 
danq said:
if it isn't an illusion,
maybe there's something (like a fouled thread) preventing the lens from being completely screwed in?

(I can see the warning sticker:
"WARNING! if resistance is encountered, do not attempt to screw in lens"  ;-)
Click to expand...


He says that when he is screwing the lens in, he can see the spot get gradually smaller and smaller until it begins to get larger again.  He is focusing through the point of convergence.  It appears to be working correctly.  If it was an obstruction, I would think that the spot would be distorted.

Peace,
dave
 
Dave -
 it's the last thing a technician wants to have to say to the user; but if the hardware is working correctly, and there isn't any software involved, then all too often the problem is the wetware... "operator error".

EDIT: your first 2 sentences above appear to describe my consciousness lately!
(and if that doesn't make sense, I rest my case)
 ;-)
DanQ
 
danq said:
Dave -
 it's the last thing a technician wants to have to say to the user; but if the hardware is working correctly, and there isn't any software involved, then all too often the problem is the wetware... "operator error".
 ;-)
DanQ
Click to expand...


helpdeskfire.jpg
 
:D well one of my problems i know now....is the lack of voltage i am putting into it, when i was unable to light the match i had it hooked up to 2x cr2 batteries (6v), when i did light the match i had it wired up to a 9v battery.....
so i'm 1.4v short of that sweet spot.

are there any batteries that are about the same size as CR2 that i can use to get the 7.4v? i'm using the coleman max LED host that takes 2x CR2 batteries......and i would like to keep the host if possible.

the focusing isn't too bad, just doesn't seem to focus as well as my red laser did.
 
john_lawson said:
those are 3v i was looking for 3.6 volt ones but can't find a supplier
Click to expand...


Let me recharge a couple to see what the fully charged voltage is.



Mohrenberg said:
the focusing isn't too bad, just doesn't seem to focus as well as my red laser did.
Click to expand...


Yeah. The violet light (405nm) is harder to "focus on" and it is MUCH more easily scattered by the air. As I said, it will NEVER look as clean as a red or green laser.


Peace,
dave
 
daguin said:
[quote author=john_lawson link=1230947281/20#26 date=1231003172][quote author=robjdixon link=1230947281/20#25 date=1231002892]You can use 3.6v CR2 batteries
Click to expand...
I cant find any cr2 3.6 anyone else know where to buy them  :-?[/quote]
http://www.dealextreme.com/search.dx/search.cr2#400
Or simply search "CR2" in Google to find a domestic source.  They are used in cameras.
Peace,
dave[/quote]


I've just recharged a set of these batteries.  Fully charged they give 3.5V.  I guess we'll have to try the 3.6V ones from eBay

Peace,
dave
 
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