Project : Laser By Batteries

[PitchouN]

Oh ok i haven't thinked at that. :cry:
So sorry i can't help you, but good luck for the project

[Genesis]

ok i think to know why you can't measure any current and the measure have no effect on the laser
here:
http://www.aidan.alpha-networks.co.u...s/DSC00692.JPG
i think the cutted track is on the both sides of the card

here is another test



and do the same thing.
measure the DC current flowing between the two points.
if there is no electrical connection between the points the laser is OFF?

[Aidan]

Ahh, i will check tonite hopefully and get back to you asap.

Thanks,

[Genesis]

no problem
i'm waiting some news

[Aidan]

Ok, I have cut that track now the laser dose NOT turn on when power is applied.

Once I bridge the track with the ammeter the laser turns on (flashing / pulsating).

On DMM setting 200m I got fluxuating readings of between 65 - 85.

There seemed to be a pattern of 6* > 7* > 8*. (EG : 65 > 75 > 85)

Thanks,

[Genesis]

this is because you need to use the next measure step (ex: 1A)
the laser fluctuaton is caused by the internal resistance of the amperemetr in 200mA step.

[Aidan]

My DMM only goes up to 200m. And its meant to be fused with a 250ma fuse.

(I have wire bridging the fuse holder)

So i need to get a better DMM to measure higher readings?

Thanks,

[Genesis]

yes i think because a laser diode for dpss work with more than 200mA i think.
but if the wire in place of the fuse has a large diameter there is no problem of voltage loss. perhaps an over range reading but no flashing/pulsating or this is a wrong electrical contact. please make sure to have good electrical connections between the tracks and the amperemeter probes.

[Aidan]

Ahhh I was taking the readings on the legs of the component.

So I am meant to take the readings off the track direct?

I will see if i can get a new DMM also.

Thanks,

[Genesis]

you can remove the green varnish (i not know if this is the good word) on the tracks to make good contact with the probes (near of the cutted tracks)