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FrozenGate by Avery

how do i check if diode works?






Check out "Reply #274" on that Thread.... that is a Test Load for
a Red LD... add 2 more diodes for a Blu-Ray Test Load...

Connect a 1 Ohm Resistor in series with your Test Load and measure
the voltage across it when your Driver is running.... (1mV=1mA)
A 1 mV reading is equivalent  to 1mA of current through the Test load... ;)

Jerry
 
nosebleedXD said:
how do i get to reply 274 ? so many pages =[ rofl [sorry i am noob]
Click to expand...

Well... look at the top of this post.... It is "Reply #19".... that is the 19th post on this thread....

So you are looking for the 274th post on the Thread I gave you...

Go to the top left of the first post on a page and click on "ALL" pages....
and scoll down to the 274th post... they are in numerical order...  8-)

BTW... it wont hurt you to read that DDL Driver Thread..... ::)

Jerry
 
kk im putting my driver together

btw which way do i turn my pot so i dun fry my diode when i connect it
 
Use ur DMM to check the resistance of the pot as u turn it ::) U'll know which way to turn it then.
 
Use ur DMM to check the resistance of the pot as u turn it U'll know which way to turn it then
Click to expand...
High resistance on the pot is = to lowest ma output.

Regards rog8811
 
im having trouble connecting the lm317 and the varible resistors

the pins are so close together
 
I hope you use a test load for your circuit first, so that you know how much to set the current to, and whether the circuit actually works. You won't want to fry your diode while testing it for whether it works or not. (If not, you'll get two results: It doesn't work, or it did. Either way, it's not now!)

Also, be carful when soldering the LM317. Don't let it get too hot! IC chips can't stand heat very well, although better than laser diodes. Clip on a large piece of metal to the back of the LM317 while soldering (I used a pair of scissors)

And, I'd recommend starting around 30mA, increasing to 100mA maximum without a heat sink. 30mA is to check whether it works, and 100mA is to check whether it's worth keeping. If a red diode can't stand even 100mA, not really much use compared to a 5mW pointer which uses less current and serves the same job.

On top of that, remember to discharge the capacitor after you disconnect the battery from the cirucit. A wire across the capacitor terminals will do. Some people have fried their laser diodes accidentally when somehow, the capcitor had remained charged, and contacted the diode giving a pulse of laser light that marked the final cry of the diode.

Btw, don't triple or double post. There is a function to edit your posts which can be accessed through the "Modify" button.

Lastly, good luck!
 
kk for the test load, it says i need 4 in4001 but i dun have a 1 ohm resistor =[

could i just use a multimeter to test load it?

and about the capacitor, im confused

and once again the lm317 and pots, how do i connect those, the pins are so close together

could i bend them? i dun want the pins to snap off like my resistors, but i bent those like alot
 
Yes, you can bend the pins, they're just wire. Just don't do it too much or they'll break off.

The 1 Ohm resistor is so your multimeter is not in line with the current path. This can be bad because you don't know how the circuitry in the DMM will affect the circuit as a whole. In addition, some cheap DMMs only go up to 200mA, whereas their voltage measurements can go higher. Finally, there is a risk that you might burn out your DMM, or at least blow out its fuse, if there is a large current spike. This can come from the circuit layout, or more frequently, if you accidentally forget to switch the cables when measuring something else like voltage (the current measurement is like a wire, which can cause a short in a circuit).

You know, you might want to invest in some good parts and equipment, as well as some more knowledge, before you accidentally blow out your more expensive components (the laser diodes). I'd go on Mouser.com and buy like $10-$20 worth of components. This can include a variety of resistors, diodes, caps, etc. That way you don't have to worry about burning out some, or lacking them. It sure beats burning out your $15 laser diode, or $30 DMM.
 
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