IgorT said:
Sure, but the standard has to be a
standard.
Measuring the current, and all of the other tests are NON INVASIVE. They don't change anything if done like ZomB and i recommended. They will just make sure that the standard really is what it should be.
Besides, lasers and meters are not humans. They don't suffer from placebo effect.
Murphy's law is a generalization of the placebo effect towards non animate objects that still have health and can die (figuratively).
danq said:
umm...
scuse me, but I think you're all spinning your wheels unnecessarily.
We will know so much more after I do an 80 degree test, and after Kenom re-measures them.
If I find that temp made the difference, then we'll know that temperature is critical for this driver/diode pair.
If Kenom finds that the 405nm is putting out 65mW instead of 75, then (a) the driver's whacko or (b) Kenom actually set it to 65 (ie he's whacko).
but until we get that data, it really doesn't matter how many angels are dancing at the focal point...
I'm back early; will do the measurements Saturday or Sunday.
DanQ
I think you may have some catch up reading to do. We've already moved past that point. If the diode is in a kink, then it will prove that it is very temperature dependant, and we don't have to do explicit temperature measurements anymore.
If you have a variable PSU at your disposal then it would be ideal, then you can make a graph. Just try not to go past the current the driver is set at to prevent optical degradation. If the driver is regulating, you wouldn't be able anyway, but we don't know that at this point. So, measure the current with *your* ampere meter when powering it with the original power supply first.
danq said:
I'm hoping you have a variable PSU, Kenom?
I'm hoping it doesn't come to that! if so, he'd better do that test very carefully!
all in all, it would be best to leave it like it is, if it appears stable - and so far that seems to be the case.
but if it's not regulating, then I'd have to ask: is the european input voltage going to be different??
Testing it with an external PSU does not invalidate the experiment because it doesn't change anything to the driver or laser (if done right)
Danq, can you do the graph testing? Depending on the results we may or may not even have to send it back to kenom.
If it turns out to be out of regulation, the experiment is nullified
If the regulated current is in a kink, the experiment is nullified
If not, we'll discuss further actions.
I'm also thinking of yet another simple test to see if it is in a kink. Hold a lens in front of the laser while it is on and observer the spot. If it is clean TEM00, it's ok, but if it is slightly to the side (not in the middle) or worse, the diode is either in or after a kink. (more testing required)
Kenom said:
The european voltage will be different only going into the power supply. It's a regulated psu so that's not going to make any difference as the output voltage is still going to be the same regardless of input voltage (as long as nothing is broken in it)
I can test if the PSU really performs the same for 100V or 230V. I have a variac at home. It's not capable of 60Hz though.
I can also use my oscilloscope to see if there is any ripple from the 50Hz present in the output. If built improperly, it may suppress 60Hz ripple but forget about 50Hz. (or no suppression at all, which I can not test for)
Maybe IgorT can do the same, as he's before me?