Hi Jem
Yes a pull-down resistor may help extinguish the reds if they are floating
usually they are OFF in this condition, However they may still appear ON with a very low (below a mw) output, This is because the the diode is still putting out some light even tho it is below threshold. acting like an led.
This could be caused by two things..one is of course the output of the DAC is not completely turned off according to the diode. and we use a high impedance input circuit ) around 10k ohm. therefore depending on the boards
drive it may not be pulled-down to off completely. Altho this high of an impedance it should be easy to to drive.
The other may be, that we purposely try not to toggle the diodes from completely OFF to full ON as this is not good for the diode facet.
Each driver is the same but diodes are not electrically. so some will do what you are describing, while some will not do this. I have found that some diodes will still appear to output some light even tho the current is way below the threshold, the threshold is around 85ma to lase while a few milliamps will make some light. Thats why we suggest the use of a shutter.
Hope that helps.
As far as the 315's power, P6 is the calibration pot on the head.
with age it will change from the factory setting.
Your software still thinks its at that setting as it was calibrated there.
You will need to measure with a calibrated power meter to make the decision
whether to change that setting. However, that setting is interactive.
meaning the power out the head will change as well.
Perhaps there is a change that could be made in the sotftware for calibration purposes, I dont know.
I am not fimiliar with the digital sw as very few people actually have it and you are the first that we are aware of that actually got that digi controller.
Very lucky to be sure..the rest of us have to use the analog controller as-is.
I have acquired heads that were set at 100mw from the factory that have been anywhere from 85mW to as much as 130mW, depends mostly on the heads age and condition.
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