As discussed at the meeting earlier this week, we will use some old *MOPA* channels for interfacing with the PLL system Jon is setting up. He is going to put a sketch+photos up here shortly, but in the meantime, Koji helped me identify a channel that can be used to tune the temperature of the Lightwave NPRO crystal via front panel BNC input. It is C1:PSL-126MOPA_126CURADJ, and is configured to output between +/-10V, which is exactly what the controller can accept. The conversion factor from EPICS value to volts is currently set to 1 (i.e. EPICS value of +1 corresponds to +1V output from the DAC). With the help of the wiring diagram, we identified pins 3 and 4 on cross-connect #J7 as the differential outputs corresponding to this channel. Not sure if we need to also setup a TTL channel for servo ENABLE/DISABLE, but if so, the wiring diagram should help us identify this as well.
The cable from the DAC to the cross-connect was wrongly labelled. I fixed this now.
Covid 19 motivated me to revive the summary pages. With Alex Urban's help, the infrastructure was modernized, the wiki is now up to date. I ran a test job for 2020 March 17th, just for the IOO tab, and it works, see here. The LDAS rsync of our frames is still catching up, so once that is up, we can start the old condor jobs and have these updated on a more regular basis.
The 40m summary pages have been revived. I've not had to make any manual interventions in the last 5 days, so things seem somewhat stable, but I'm sure there will need to be multiple tweaks made. The primary use of the pages right now are for vacuum, seismic and PSL diagnostics.
The summary pages were in a sad state of disrepair - the daily jobs haven't been running for > 1 month. I only noticed today because Jordan wanted to look at some vacuum trends and I thought summary pages is nice for long term lookback. I rebooted it just now, seems to be running. @Tega, maybe you want to set up some kind of scripted health check that also sends an alert.
The summary pages had failed because of a conda env change. We are dependent on detchar's conda environment setup to run the scripts on the cluster. However, for some reason, when they upgraded to python3.9, they removed the python3.7 env, which was the cause of the original failure of the summary pages a couple of weeks ago. Here is a list of thoughts on how the pipeline can be made better.
Remember that all the files are to be edited on nodus and not on the cluster.
I updated the config file c1pem.ini in /users/public_html/detcharsummary/ConfigFiles, and commited it so I hope it works, but I did not have git push permissions. Does anyone know what is the idea here? Should we do our own personal git clone and modify that way or shoudl we do it with the control account.
Wiki needs to clear out all the outdated information on this workflow.
The changes are to make the y-scales useful. Currently, all of the past seis BLRMS plots are not so useful because the scales have not been set based on the actual signal levels. Let's see if this works, and we can re-evaluate after a few weeks.
Score: HP Analyzer 1
Rob & John 0
Amplitude of 29.485MHz input sine wave [dBm] | Value of channel C1:IOO-MC_DEMOD_LO
-------------------------------------------- | -----------------------------------
-10 | -0.000449867
-8 | -0.000449867
-6 | -0.000449867
-4 | 0.000384331
-2 | 0.00526733
0 | 0.0199163
2 | 0.0492143
4 | 0.0931613
6 | 0.161523
8 | 0.229885
10 | 0.293364
- Use LEDs of a wavelength that the OSEMs don't see. LEDs are also cool so that the
Suspension won't drift in alignment.
- Use 2 power supplies so that the power is balanced.
- Make is +/-12 V twisted AWG 14 wire so that the EMI is contained. Should also
be shielded cable.
The attached plot shows that someone broke the MC_SUM_MON channel around 10:30 AM this past Wednesday the 11th. This is the EPICS monitor of the MC error point.
Come forward now with your confession and I promise that I won't let Steve hurt you.
I checked a broken QPD, which was placed for PSL angle monitor, and finally I cocluded one segment of the quadrant diode was broken.
The broken segment has a offset voltage of -0.7V after 1st I-V amplifier. It means the diode segment has a current offset without any injection of light.
Tomorrow I will check a new QPD for replacement.
Today I checked out the SR560 around the lab. I confirmed that the one with the label "channel A noisy" is effectively mulfuctioning.
It was coonected to the lock-in amplifier set up for the drum mode peak readout.
I repleaced that with a working one.
I borrowed SR785 to measure AA, AI noise and TF.
Eric Gustafson is handling the old HP4291A rehabilitation. Tarac picked both units up today.
March of 2008 Tucker Electronics failed to fix it's intermittent ~25MHz 0.5V oscillation at the swept sine output
See 40m-elog id:398 on 3-24-2008 by Rob Ward