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Ongoing purchase for Sony 16X dvd diodes

S

SenKat

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TheMonk said:
I am very excited to receive my diodes today from GB #3, :) but when I connect the first one to the Dorcy Mini the light was dime much like the 5mW Aixiz diode.  :-? The second diode was very bright, anyone knows what is wrong with my first diode.  ::)

Each diode is different - so it is really hard to say :( I have had some that are like that, and others that appeared to blaze like CRAZY right away, then dim off to nothing after a brief period of time :( Also - the SLIGHTEST ESD charge can murder these poor things - so before opening that little box that I ship them in - make sure you are grounded very well :)
 





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Gazoo said:
[quote author=Kaspar389 link=1188959908/30#43 date=1189311595]I understand what you mean.

I really wouldnt like to spend more than like..10 more dollars on this whole project. I would like it to be compact also.

No offence or anything, im not that into lasers, I just want one to fool around with, and plus, i would only use it outdoors, and places with no places to reflect.

Please, dont worry about my safety, but please point me to a link where I could make the LD last longer, without carring a driver( i think thats what that thing is, the one for 25 dollar) around.

-Thanks

I take no offense....but I am concerned about the safety of others vision, especially new comers to this forum, and I have a very good reason for it. We all do.

Having said that you will need access to a soldering iron or maybe you have a friend that has one and knows how to solder?

The resistor is put in series with the diode. I would recommend a 2 ohm .5 watt resistor if you are going to be using a minimag with two cells. The electrolytic capacitor goes across the diode. The recommend value is a 47uf 16 volt capacitor. The capacitor will be marked with the negative side. The negative side of the capacitor gets soldered to the negative side of the diode, and the positive side of the capacitor to the positive side of the diode.

+-------------resistor--------------+ diode.
+ l
l
---------------capacitor-----
l
- l
- ------------------------------------- diode

This will provide some protection.[/quote]
I know how to solder.

I just, dont understand your...drawing

Although creative :p
 
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try this one
+ power in---{resistor}---+------|--------\
c |LASER |
a |DIODE
p | |
- power in-------------------+------|---------/
 
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BlueFusion said:
try this one
+ power in---{resistor}---+------|--------\
c |LASER |
a |DIODE
p | |
- power in-------------------+------|---------/
What does a resistor and capitator do?

Can someone make a little....picture tutorial?
 
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Cap: Filters voltage jumps and spikes that the LD can't take.
Resistor: Provides a basic low level current limitation to avoid cooking the LD instantly.
 
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Ah yes the cap + resistor circuit does work though I still manages to spoil an 8x diode with it. Not sure if it was esd or the cap discharging that killed it though. I used a different cap though 33uF 25v electrolytic wonders if it makes a difference?

I've seen some drive circuits with extra 0.01uF ceramic caps? Can someone explain how this helps?
 

chimo

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xarylx said:
I've seen some drive circuits with extra 0.01uF ceramic caps? Can someone explain how this helps?

The smaller cap will be "faster" acting (lower esr) for transients (spikes) than the larger electrolytic. Think it as capacitor "inertia". Sometimes bigger is not better.
 

Things

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lower capacitance will react faster as someone already said, but higher capacitance ones will take bigger spikes and keep the power very level. i think someone already mentioned this, but if your capacitor is too big, you will get heaps of losses, and not much power will get to the diode. also big caps have a very good chance of killing the diode if they are disconnected, simply because they can store more power.
 
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i am such a noob with electronics can i ask someone what the uf in the 47uf 16 volt capacitor means
 
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Gazoo said:
[quote author=Kaspar389 link=1188959908/30#43 date=1189311595]

The resistor is put in series with the diode. I would recommend a 2 ohm .5 watt resistor if you are going to be using a minimag with two cells. The electrolytic capacitor goes across the diode. The recommend value is a 47uf 16 volt capacitor. The capacitor will be marked with the negative side. The negative side of the capacitor gets soldered to the negative side of the diode, and the positive side of the capacitor to the positive side of the diode.

+-------------resistor--------------+ diode.
+ l
l
---------------capacitor-----
l
- l
- ------------------------------------- diode

This will provide some protection.

The message is for Gazoo or anyone who can answer I just drew out the pictures of what your setup would look like. can I use this setup instead of buying a circuit board? I understand that the LM317 circuit board does a better job of regulating but if i used this setup it would be better than connecting the didode directly to the batteries right?

here is a clearer picture of your diode set-up with battery (it's not all that great but I tried my best to label everything) ;D
 

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Gazoo

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mhouse974,
Yes that will work and thanks for the drawing...sometimes I get lazy.. :) Remember however you are using the circuit at your own risk. This circuit is the bare minimum, but is better than nothing, and will provide some protection. But it will not keep your diode as safe as Daedal's circuit.

Do not use more than two AA or AAA batteries with the circuit..
 
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rubberband said:
i am such a noob with electronics can i ask someone what the uf in the 47uf 16 volt capacitor means

The u is a substitute for the lowercase of the Greek letter "mu" (this is fairly standard on the net, since it's much easier to type u than insert a symbol for mu, which is often not posible at all). This is the symbol for the "micro-" prefix in SI (metric). So, 47uf is 47 microfarads, or 47*10^-6 farads.

Make sense?
 




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