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ArcticMyst Security by Avery

Need help trouble shooting.

ARG

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Hey everyone,

I'm almost done my projector, so I decided to put it through some testing :D

Unfortunately there was a problem... My blue laser seems to fade halfway through graphics... No idea what the problem is. I'm hoping someone with more experience knows what is going on.

Setup:
DT-30's
FB3/QS

Laser:
FMP3 set to 1.25A
A140 diode
12V 3A PSU
G-1 lens + prisms

Picture:
t1W6e.jpg


In this one the green laser is also on, but the green cuts off because of the fast shutter speed on the camera, but you can still see how the blue fades out.

uDsFI.jpg
 





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Could be overheating of a critical component somewhere along the blue module's line.
Main op-amp perhaps, or the driver?

Blue is the one with highest current consumption, correct?

Check some temperatures on critical components, see if anything needs heatsinking, post back :) And good luck!
 
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With all graphics? Do the test frames do it, too? Many lasers don't lase until a point much after 0.02V on the analog input. Some don't turn on until 2V. If there is fading in the frame, it could just be fading below this point.
 
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ARG

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With all graphics? Do the test frames do it, too? Many lasers don't lase until a point much after 0.02V on the analog input. Some don't turn on until 2V. If there is fading in the frame, it could just be fading below this point.

Nope, it does this with test frames as well. Thinking back it probably would've been more helpful to take pictures of a test frame.

Could be overheating of a critical component somewhere along the blue module's line.
Main op-amp perhaps, or the driver?

Blue is the one with highest current consumption, correct?

Check some temperatures on critical components, see if anything needs heatsinking, post back :) And good luck!

I don't think anything is over heating :thinking:
The power supply seems fine and the flexmod is screwed onto the baseplate with thermal paste, same with the galvo amps. Nothing feels warm to the touch either, so I assume that's not it...

The blue is using the most current.
 
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is the intensity up all the way? also check your color assignments what is missing maybe a red signal..
 
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Maybe your power supply is starving the lasers, and that fade-out is the capacitors losing charge?
 
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Things

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For some reason I only have BEYOND installed on this machine and not Quickshow, but I have found that having it on the "Analog with log response" can sometimes cause issues like this. Make sure it is on either TTL or linear response and see if that helps. If not, try set a min voltage on the blue laser in QS and see if it still does it. Those might not be the correct names, but they should be pretty close.

EDIT: You could also have a floating pin. Check sure your modulation connections are solid.
 
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ARG

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Well, I feel pretty stupid at the moment. I went to go plug the blue laser into the red channel to see if it was a problem with the blue channel and the GND wire for the modulation fell out of the connector. Got a new connector and it works great now!

Thanks to everyone who helped out! +1
 
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Oh I hate floating wire problems. The worst part is that they often take on the "value" of the neighboring wires, so they're very hard to diagnose.
 




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