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Group Buy # 3 For Sony 16X DVD Burner Didoes

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Knasterpijp

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Gazoo said:
Yes, there are much more efficient regulators similar to the one Daedal used in the same type of package. The main reason Daedal used the LM317T is availability and price.

If you do a search on google for low dropout voltage regulator. I am sure you will find something more efficient. Also keep in mind that Eric will soon be posting a feeler for group buy laser diode drivers. The EU-37 and EU-38.
Click to expand...

Ok imagine, that i find a more efficient regulator, do i have to change the diode, resistor and capacitator type aswell, or can they stay the same??
 





Gazoo

Gazoo

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Yes, and I had to get this through my thick skull. If you think of voltage and current like water flowing through a pipe it becomes easier to understand. Following is a link to a web page that helps explain in these terms:

http://www.zyra.org.uk/voltamp.htm
 
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chimo

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See my post #7 here: http://www.laserpointerforums.com/forums/YaBB.pl?num=1187988356/7#7

Paul

Knasterpijp said:
[quote author=Gazoo link=1187465349/105#106 date=1188168034]The voltage drop of the LM317 is 2 volts. Add to that the silicon diode in Daedal's circuit and you end up with at least a 2.5 volt drop, plus the voltage to over drive the diode which can be anywhere above 2.5 volts, depending on how brave one is. This is why it is recommended to use 6 volts with his circuit. If you leave the silicon diode out, you can easily get by with 5.5 volts.

I agree a constant voltage source is needed for the current to be truly regulated. It is very easy to build a voltage regulator using an LM317T, or one could even get a 7805 5 volt regulator, and put a silicon diode in series with the ground which would raise the voltage to 5.5 volts. In this case, using Daedal's circuit and the 5 volt regulator, the minimum voltage required would be 8 volts.
Click to expand...

hmmm
Gazoo, do you think there is another type of the LM317 series with a lower voltage drop, so 4,5 volts(3x 1,5volts AAA) works with the circuit?? Because in the Netherlands, 6volt flashlights are hard to get for a reasonable price  :(
If it cant be done, then i have to online shop again for the 6volts flashlight which daedal is using.  I've build his circuit already, but naturally it only works well on 6volts.[/quote]
 
Gazoo

Gazoo

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Knasterpijp,
Sorry I missed your post. Yes, you can use all of the other components you already have.
 
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BlueFusion

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Guys... head over to the appropriate thread in the experiments and mods section. This thread is only about buying the LD.
Interesting stuff, tho...
 
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Knasterpijp

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BlueFusion said:
Guys... head over to the appropriate thread in the experiments and mods section. This thread is only about buying the LD.
Interesting stuff, tho...
Click to expand...

Yeah you're right, sorry! ::)

Offtopic: Thnx paul and Gazoo!! It is indeed interesting to make a small and effecient LD flashlight, but i think, since i already bought all the parts matching the 6VOLTS, the best and easiest thing i can do, is ordering the 5W MXDL 2xCR123A flashlight and aim done. Maybe i make a small one later. Don't you agree? ;D

OT: Senkat, have you received the LD's yet?? :cool: Send them towards us, we cant wait any longer! :-/ at least i cant ;D

thnx guys!!!
 
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Daedal

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Gazoo said:
Yes, there are much more efficient regulators similar to the one Daedal used in the same type of package. The main reason Daedal used the LM317T is availability and price.

If you do a search on google for low dropout voltage regulator. I am sure you will find something more efficient. Also keep in mind that Eric will soon be posting a feeler for group buy laser diode drivers. The EU-37 and EU-38.

http://www.roithner-laser.com/Drivers.htm
Click to expand...

Has anyone looked at the LM2991 as a viable option? This is what I'm basing my next circuit on. :)

--DDL
 
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ericab

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OT: Senkat, have you received the LD's yet?? :cool: Send them towards us, we cant wait any longer! :-/ at least i cant ;D
Click to expand...


agreed! whats the news SenKat!?!
 
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SenKat

Guest
They have not arrived yet, folks - I will update the thread as soon as they arrive, I assure you ! The Fedex tracking still says, in transit ! ARRRGH ! The wait is killing me !

G !
 
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wilheldp

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SenKat said:
They have not arrived yet, folks - I will update the thread as soon as they arrive, I assure you !  The Fedex tracking still says, in transit !  ARRRGH !  The wait is killing me !

G !
Click to expand...
Good...my circuit still needs tweaking and it would kill me if the LD was here and I couldn't drive it. ;)
 
Hemlock_Mike

Hemlock_Mike

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Hey guyz --

When dealing with that area of the WORLD ----  Expect delays.  Look at complaints about Deal Extream and others there.  I don't know how they ship but water buffallo demand days off too  like our PO !!!!

Mike

Use this time to get your parts, meters power supplies, etc in order for the big day. It will go smoothly if you are ready.
 
Benm

Benm

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With shipping from asia your mileage may vary, though i have good experiences with most goods coming from for example hong kong.

Just hope there aren't any customs problems, i bet there must be some sorf of import tax on these things in the us?

Speaking of which.. if you send these diodes onwards to europe, kindly mark all packages as gifts or samples with a value lower than $20 or so - otherwise we get a big tax bump up here.
 
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SenKat

Guest
Benm said:
With shipping from asia your mileage may vary, though i have good experiences with most goods coming from for example hong kong.

Just hope there aren't any customs problems, i bet there must be some sorf of import tax on these things in the us?

Speaking of which.. if you send these diodes onwards to europe, kindly mark all packages as gifts or samples with a value lower than $20 or so - otherwise we get a big tax bump up here.
Click to expand...

You betcha ! All shipments across the pond are marked as electronic parts, as gifts, and values at $20 or less unless requested otherwise. Yeah, I do have to pay the import fees on these, which fortunately is not that awefull much, but it is still a headache to have to pay for it once, and then again to get it inside your own country...what happened to no taxation without representation ? GAH ! ;)


G !
 
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BlueFusion

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Hmm, I should start putting my circuit together. I was thinkin of using a 1W LED to test on, as it will suck as much current and voltage as possible, being rated slightly higher than the LD. That way I can get the current right.
lelele cant wait!!!
 
Hemlock_Mike

Hemlock_Mike

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YES -- Bluefusion ---

Way to think !!! That's what I use as a preliminary test bed !!! Do your measurements with that throw away so you know how the circuit responds to a big diode. I should have posted this long ago but YOU beat me to it ;D Good work and an important post.

Mike
 
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