Dummy load for a greenie?

[MTWallet]

I will be building a dummy load for red/violet units, and am wondering why there is not one for a green. Is it because the power input is really related to the output of the IR laser and the green output is just a variable sub-power (based on crystal alignment, quality, etc) and you really have to just measure its output with a meter?

 

[rog8811]

The only reason you won't find that info is that, with 1 exception I can think of, green lasers come with drive circuit attached.  
You are right in thinking that the driver is set up to the IR LD so you could try a test load suited to IR LD's..... I have a feeling that you need less than 4 1N4001 diodes for them but have never had to find out.

Regards rog8811

 

[MTWallet]

I have a feeling that you need less than 4 1N4001 diodes for them but have never had to find out.

Regards rog8811

Thanks for the reply, and sorry not to have posted back sooner.  I've been waiting for my replacement LD and an adapter to come in before I dove back into this.  Is there a thread somewhere about the logic behind the dummy load?  Like why for BR you use 6 1N4001's and only 4 for red?  Oh, and if a 5mw Mobolazer 'Lil GBeam isn't on your list of unattached drivers, you can add that one.   Thanks!

 

[rog8811]

What is the logic behind the dummy load? Like why for BR you use 6 1N4001's and only 4 for red?

Different colour LD's need a different voltage to drive them, the 1N400 series diodes we use for the dummy load drop .7v each
A red needs around 3v so 4 diodes @ 0.7 = 2,8v
A Blu ray needss around 4.5v so 6 diodes @ 0.7 = 4.2v

This may help with your original question
As I need to test a greenie circuit, the IR LD's usually run @ 2.5v so I will try 3 diodes @ 0.7 = 2.1v


Regards rog8811

 

[ElektroFreak]

Check your other thread: http://www.laserpointerforums.com/forums/YaBB.pl?num=1230744297/40#40

I posted an explanation and schematic there if no one has given them to you yet...

 

[shall]

^^