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Message ID: 2514
Entry time: Fri Nov 6 12:45:21 2020
In reply to: 2513
Photodiode testing recovery status
Embellished Chris's PD MEDM screen a bit to illustrate controls in a diagram. The representation of the RELAY SWITCH between the Keithley and the SR560 is a bit off - I think the transimpedance amplifier is switched out as well.
Also - Keithley bright PD sweep output is attached.
Quick update, more detailed update to follow.
- Laser is working
- Photodiode sweep with the Keithley shows a sensible dark Current v Voltage plot (when laser is off) - indicating that PD wiring is still intact
- Laser was aligned onto photodiode (although it took a while aligning to find the signal)
- Ran a sweep with the Keithley and the laser on - saw another sensible bright Current v Voltage plot (more current than in the dark case)
- DAQ control still works
- DAC output is directly providing (unfiltered) 200mV bias
Still to do:
- Get the SR785 plugged back in
- Get an SR560 inserted between DAC output and PD bias to low pass filter
- Investigate why the laser current set point is so noisy
- Sort out RTD situation inside the chamber
- Miscellaneous stuff