S. Muusse, G. Valente

Electronics integration

We are running into some issue with the linear translation stage and rotation stages which we can't operate through the medm. Both stages are operational when using a newport motor driver and when driven through directly through beckhoff into the CHETA chassis and motor driver chassis but havent been shown to work with the code taken from the CO2 rotation stages. Patrick has been looking through the software but we are yet to find the solution. Yesterday (02/26) we determined the motor power cables from the CHETA chassis to the motor driver chassis were crossed which was a possible source of this issue, however, this was consistent with the wiring in the motor driver chassis albeit unorthodox. We elected to modify the cables so they are wired conventionally and in turn changed the wiring in the motor driver chassis by switching the + and - wires at the back of the chassis where the power is outputted. Now internally  the black = positive and red = Negative which is unfortunate but the best solution. We have seen both stages work after this effort using the newport motor driver so we dont believe this is the issue. 

Setting up Table 2

Table 2 is in the process of being populated. Today we installed the PD system using the electronics to align the PDs and also have inserted the first telescope lens. Initially, when installing and aligning the PDs the PD power supply chassis was supplied with pos =+24 and gnd =0V instead of ±18V leading to both PDs outputing -11V. This fried the first transimpedence amp in the circuit board which we have now replaced with alot of help from Marc. Both PDs are now working and aligned on the table. 

Calibration and power budget on table 1

We measured the power after all optics, where the powermeter fit ,as well as the I[A]/P[W] relationship of the laser to calibrate laser power on the MEDM.
The min/max power that can be achieved using the waveplate in rotation stage and the 2 polariser was measured:
Min ≈20mW ,
Max = 1.44W 
Both powers were measured after the 2nd polariser. This corresponds to a maximum power which can be output off the table of 1.308W, which was measured after the last pickoff. 
I'll attach plots/ figures in the comments showing these measurements.