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Hi Listers,

I have a technical question regarding the tuning of PMT modules on a confocal 
system.

We have recently replaced a PMT module on our LSM5 system.  Although we 
now can get a signal and observe our cells we still having what looks like 
electrical interferences (horizontal stripes) that impact the quality of our 
images when scanning.
The image acquisition now requires a much lower laser power (633nm line) 
than previous, but inversely, an extreme detector gain was needed (over 
1100!). If I try to increase the laser power and decrease the PMT voltage it 
looks like the PMT saturates or there is no more signal.
Other channels/lines have clean signal. Nothing wrong with the optics.

Is there any electronic engineer or specialist with any thoughts regarding 
adjustments, tweaking, or calibration of the PMT module? Or any pin on the 
board that I should check to see if the control voltage to the PMT is right?

Thank you,

Ben