New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics 
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| today, we were able to store more than 93kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio |
New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, we were able to store more than 94kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 93kW in the FP cavity, always |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, we were able to store more than 95kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 94kW in |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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today, we were able to store more than 97kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 95kW in the FP cavity, always |
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New power record in ThomX cavity, posted by Ronic Chiche at ThomX igloo about lasers and optics
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yesterday, we were able to store more than 98kW in the FP cavity, always with the same parameter : 33% laser amplifier ratio
Ronic
Chiche wrote:
today, we were able to store more than 97kW in |
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33MHz phase adjustment, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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the 33MHz beating signal (phase) is used to start and stop automatically the lock on the 500MHz beating signal.
this 33MHz beating phase has a fixed range (typically +/-0.5V), so it is important to center this beating phase in the middle of its own range
when the 500MHz signal is locked |
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air conditionning in ThomX Bunker, posted by Ronic Chiche at ThomX igloo about lasers and optics
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The temperature slitly increase in thomx Bunker from 23° to 24° during the last day.
The thermalisation of the CFP is very long...
In any case the operation of the CFP is so easy, it seems to be correlated to the weather... tody it's very nice as of hte rest of the week. |
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air conditionning in ThomX Bunker, posted by Ronic Chiche at ThomX igloo about lasers and optics
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after the new temperature setting for the bunker air cooling (winter to summer transition), the temperature drop from 24° to 20°C which induced
a slight misalignment between the onefive oscillator and the fiber injection.
the amplifier photodiode PD_IN which checks the amplifier power injection drop also from 3mW to 2.885mW... hopefully, it is enough to start the |
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air conditionning in ThomX Bunker, posted by Ronic Chiche at ThomX igloo about lasers and optics
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I finally got 93-94kW for 33% amp ratio.
I had to move the FP-cavity length to compensate the temperature change in the bunker.
doing that, I had the message "Low Limit SW pressed" when I tried to move P4z under -98 000 steps !!! |
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Electrons-Photons phase stability measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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we installed a measurement at the IP with the BPM for ion cleaning for electrons and we used a fast photodiode at the output of the FP-cavity and measured
with a fast oscilloscope the phase jitter between the 2 signals.
in red, the BPM signal |
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Electrons-Photons phase stability measurement, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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the phase between the 500Mhz ring RF oscillator and the electrons is measured on a BPM and is very stable after 2-3ms (<< 6ps, typically) !
in the same time, we can use the residual phase beating after our 500MHz mixer to estimate the phase noise coming from the laser part.
the rms noise of this signal is around 60mV for 1.25V peak (2.5 pk-pk) signal => ~ 50mrad rms |
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New direction for cavity motors, posted by Ronic Chiche at ThomX igloo about mechanics | software
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from now on, one reverts the FP cavity motors direction to compensate the long drift from the begining of the project.
the motor MOT.06 will be used for the upward direction (presently -1 082 650 steps)
and the motor MOT.03 will be used for the downward direction (presently +37 170 steps) |
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Good Xrays production trend, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics | software
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| this afternoon, we succeeded to get a quite long Xray production trend around 15-20 minutes with a flux above 25k on i1. |
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strange drift (new effect !?!), posted by Ronic Chiche at ThomX igloo about software
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today, we had a strange effect :
both the laser and the FP cavity were locked on the RF frequency (500.10045 MHz), and we were producing X-rays but with a slowing (several seconds)
fluctuation exactly as the electrons-photons phase was drifting and the fluctuation can goes to 0 Xrays produced even at the "right" phase. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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I installed an accelerometer setup in the bunker.
presently, the accelerometer is placed on top of the housing and its signal is connected to the 2nd scope (33MHz and 500MHz RF beating) on channel
4. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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today I connected a copy of the laser PZT signal to the 2nd scope CH2 (with AC coupling to remove the DC offset) to be able to monitor synchronously
the Accelerometer and laser PZT signals.
the accelerometer is still connected to the 2nd scope CH4 and placed on top of the housing. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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this morning, I did some measurement with nobody interfering with the tests.
- the "no noise" image shows a standard situation during 10s when there is no noise either on PZT or Accelerometer.
most of the time, we are in this situation. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics 8x
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then, I moved the accelerometer on top of the "X-hutch side" vessel, placed directly on the metal top case, inside the housing.
- the "no noise same range" image shows a standard situation during 10s when there no noise either on PZT or Accelerometer.
on can compare the noise level on the accelerometer with the previous post when it was outside on top of the housing. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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at the end of the day, I moved the accelerometer from the top of the cavity vessel to the top case of the Onefive laser.
I quickly saw again quite strong correlations between the vibrations compensated by the PZT and the accelerometer signal.
when one does a laser motor step which makes a systematic lock loss, one doesn't see any signal on the accelerometer. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics 6x
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this morning, I did some new plots with the accelerometer placed on the top of the case of the OneFive laser.
I previously observed with the accelerometer placed on the top of one cavity vessel, the correlation between the accelerometer signal and the PZT
noise is pretty good but not 100%. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics 7x
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new plots, with the accelerometer placed directly on the optical cavity table (on the marble part), close to the oscillator.
the correlation seems a bit better....
we would need to put the accelerometer on one foot of the table to check if the table has not some micro-movement or at the IP to check if the |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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one possible source for this acoustic noise was the vibrations coming from the water cooling of the dipoles which is normally never turned off even when
the machine is off.
this afternoon, Kevin turned off the main valve of the water cooling of half of the dipoles (the half on the FPC side), and we recorded the peak-peak |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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here is the pk-pk measurement of the accelerometer during the whole night.
the recording started at 5pm yesterday and has been stopped this morning at 10am.
one got 28k points in 17 hours => 1.65k points / h |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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here is the acquisition from 10:30am to 5:30pm
11k point in 7h => 1.57k points / h
the noise is almost the same during the daylight, a little bit increasing from 1:30pm. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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here is the same kind of measurement (pk-pk of 1 sec of acquisition) done on the laser PZT when the FP is at 90kW.
it's from 6:20pm to 7:10pm => ~2.4s by point
the minimum values are for the PZT being off. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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long term pk-pk measurement of the accelerometer (placed on the optical cavity table, on the marble part close to the laser oscillator) from 5:30pm to
9am => ~ 2.255s / pt
start of the quiet period : ~ 5k pts <=> 8:45pm |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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I installed the accelerometer on the ground close to one feet of the FP cavity hexapod (see picture) and restarted the acquisition at 6:40pm on 20th
of february.
the acquisition corresponds to the night between the 20th and the 21th of february. |
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correlations between accelerometer and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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for this 20Hz oscillation, could it be a natural resonance of the optical table placed on its feet ?
typical mass of the table m ~ 8T
feets : |
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correlations between vacuum gauges and lock losses @ 20Hz, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | vacuum
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the machine people saw a correlation between BPM jumps and vacuum gauges peaks related to breakdowns in the beam pipe.
these breakdowns could produce some accoustic noise which could be related to our lock losses.
=> we tried to do a corrrelation between our lock losses and the vacuum gauge peaks => WE DON'T SEE any correlation !!! |
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CEM noise measurements, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | cabling
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The goal of these measurements is to check if one can find some correlation between the CFP lock losses observed during a run and some CEM noise in the
bunker.
the main issue is coming from a 20Hz noise apearing/disapearing in the laser cavity PZT signal. |
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CEM noise measurements, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | cabling
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This afternoon, we started almost all the parts of the machine with Vincent and Nicolas, and we didn't see any change in the Loop noise signal.
we saw only a peak comb at 10Hz on the Loop noise signal when the septum is ON. the amplitude of the peaks is then related to the voltage on the
septum. |
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Checking the amplifier power, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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this morning, with Daniele, we checked the amplifier power, right after the CVBG (the power meter has to be placed on a metal plate above the large table
hole), and just at the input of the FP cavity, after the 1/4 and 1/2 waveplates (the power meter has to be placed on flat beam dump+ Thorlabs beam dump
+ V metallic mount to be at the right height). |
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Checking the amplifier power, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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we did a long term run (25 mn) with the powermeter located at the FPC position at 33% amplifier ratio.
the initial power was 18W .
then, it goes to 18.5W in 10 minutes, then 5 minutes later, it goes to 18.3W and stay stable until the end the run. |
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Checking the amplifier power, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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I put back and aligned the 1/2 waveplate only and I get 71kW max after its optimization and optimizing the CEP and alignment (without walking procedure).
this waveplate change a lot the reflected power seen on the CH2 of the scope.
to be continued this afternoon... |
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Checking the amplifier power, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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this afternoon, we put back the 1/4 and 1/2 waveplates and after a long alignment/angle tuning/CEP optimization process, we hardly got 80-81kW in the
cavity for 33% amplifier ratio. the transmission photodiode is then ~ 7.5 divisions (500mV/division) on the scope.
BUT during the 1/2 and 1/4 waveplate angle tuning process, we clearly saw: |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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here are the (good) lock parameters used this morning.
for the RF/FPC lock, the 33MHz beating signal used to select the right bucket is 1Vpp
=> beating signal : V0 . sin(phi) with V0=0.5V. |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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Today with Daniele and Alice, we operated to cavity.
we obtained 84kW for 33% of amplifier ratio.
we had to tune the CEP @ -565µm and the FP-cavity alignment. |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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This morning, I wanted to test quickly if the Smaract motors can be used in open loop instead of closed loop or in piezo scan.
the goal is to do very fine steps without to much vibrations (like with piezo scan mode) but with the full motor range (the piezo scan mode
has a very limited range). |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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This afternoon, we scanned the optical table vertically with the hexapod in asynchronous mode to find its optimum position, looking at the X-ray production.
then, we searched for the correct bucket and phase in the bucket thanks to the Kevin script on the 500MHz and the 33MHz phases.
we got relatively easily some stable X-rays. |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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Today, after setting the locking parameters, I got 80kW in the FPC for 33% amplifier ratio after CEP tuning (Smaract CH2 ~ -423.5µm) and alignment.
maybe the alignment has to be improved by some walking procedure.
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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this morning, I did some walking procedure and I got 82kW in the FPC with 33% amplifier ratio (after CEP optimization too).
but when I move the FP cavity motors to adjust the frequency, I cannot keep this power and it is reduced.
could it be we get a stronger correlation between axis than before in the mechanics has more rust than before ? |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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this morning, I did some walking procedure and CEP alignment to get ~80kW in the FPC with 33% amplifier ratio.
we have to check if this power drop comes from:
- a laser amplifier power drop |
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Optimizing lock parameters for stable X-ray production, posted by Ronic Chiche at ThomX igloo about lasers and optics | software
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the RF frequency is now 500.1003MHz which is equivalent (if divided by 15) to 33.34002MHz.
the frequency has to be changed by ~2kHz @33MHz <=> ~550µm /2 for one motor.
I changed the laser and the FP cavities frequency. |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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On Friday 11th of October, due to the Yvette flooding, all the AC power of ThomX have been shut down.
After the shutdown, I had to restart the Onefive oscillator but the laser modelock was lost.
I had to do a step of 1mm at 10mm/s with the Smaract motor on the rep rate channel (CH1) |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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This morning, I verified the reason why the seeder frequency was not displayed on the amplifier software screen:
one needs to start the amplifier (even at 0%) to see the seeder frequency !!!
now, we have 33.371MHz as expected ! => OK |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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After the new Yvette flooding of the last week and the consecutive AC-shut down, I restarted this morning the laser with the same procedure (step of
1mm at 10mm/s with the Smaract motor on the rep rate channel (CH1)).
now, we have again 33.371MHz and 3.1mW input power as expected ! => OK |
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Onefive 33MHz modelock loss, posted by Ronic Chiche at ThomX igloo about lasers and optics
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For the modulation/demodulation generator for the PDH signal,
after a power shutdown, on can :
1) restart the generator to get the correct parameters: |
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Characterizing Focus Tunable Lens, posted by Fatematuj Johora at Optical room about lasers and optics
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Yesterday Ronic and I worked on the high laser power measurements with the Vertical set-up of the Focus Tunable Lens. We went upto 38W@4 dpt at the begining
and then also changed the focal power at 38W.
Observation: |
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Finding correct motors position and parameters to keep the lock during a move, posted by Ronic Chiche at ThomX igloo about mechanics
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this morning, I try to find a new region for MOT.03 and MOT.06 where we can move them without unlocking the cavity.
I started from the position:
MOT06 : ~ -785 000 |
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Finding correct motors position and parameters to keep the lock during a move, posted by Ronic Chiche at ThomX igloo about mechanics
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this morning with Daniele, we did a quite long run with this motor position and it seems we don't lose the lock too much.
the motor positions are:
MOT.03 (M4): -186 500 steps |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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temperature in the casemate ~ 19.5°C stable
this morning, I measured the power directly at the output of the fiber coupler (through the output fiber), after the strecher : ~5mW
then, I connected the EOM used for the PDH technic : ~2.5mW |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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I refilled the chiller and the stabilized temperature is @ 25°C
we started the 3rd stage of the Alphanov amplifier at 30% => PD_OUT is fluctuating around 1-1.4W => it's not related to the real output
power ! |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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we had to move the laser cavity motor to find the resonances and change a lot the CEP.
the CEP motor is at -524.1µm
we got ~75kW in the FP cavity without alignment but with CEP optimization. |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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after doing some alignment (walking procedure on the Y axis), and CEP optimization, I got 83kW for 33% on the laser amplifier with a coupling of ~60%
=> we have to check the input power after the amplifier.
I adjusted the FP and laser cavity motors to have a small 33MHz detuning with the RF reference (~10 Hz of beating @ 33MHz) |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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this morning with Daniele, we are measuring the amplifier power just before the FP-cavity.
Casemate temperature @19.5°C
@0% : 205mW |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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After the summer power shutdown, I restarted all the equipements and got quickly ~80kW for 33% amplifier ratio with CEP optimization and without Alignment
optimization.
CEP motor position : -506µm |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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amplifier power measurement before the compressor CVBG.
we used a mirror in between the amplifier output and the compressor + a 2-mirror periscope to match the powermeter height.
amp ratio (%) power (W) |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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after redoing the alignment of the CVBG, we got back the initial power in the FPC (87kW)
now, I checked the RF locking signals on the 2nd oscilloscope.
I get a strange ratio between the 33MHz beating and the 500MHz beating signals. |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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now, the Ring RF frequency is set to 500.067MHz.
so the CFP/laser frequency should be 500.067MHz/15 = 33.3378MHz.
the frequency was set to 33.378MHz !!! => it explains the frequency shift only on the 33MHz beating => I corrected the frequency on the |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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I changed a little bit the locking parameters (see picture) for the RF/FPC loop and it locked rapidely.
I asked Vincent to connect on the same scope the synchro signals to check if the FPC lock was OK => he connected 33MHz signals coming from
the laser and from the 33MHz RF generator. |
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restarting CFP system after the long summer shutdown (RF section conditionning) and Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics | software
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this morning, with Vincent :
- we added the 10Hz trigger to the CH2 on the remote scope (192.168.229.21) to check the synchronization at the right timing.
CH1 : 33MHz RING |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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this morning, we tried to find the origin of the 20Hz oscillation.
- we switched OFF the laser Smaract motors controller => no change
- then, we addionally disconnected the FP-cavity PZT cable from the Laselock (we put a charge of 1kohm) => no change |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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this afternoon, we did 2 tests to better understand this 20Hz oscillation:
- we locked the amplified laser directly to the 500MHz ring reference oscillator, without any intermediate locking to the FP-cavity => no
change |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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yesterday I did 2 tests to try to understand the origin of the 20Hz oscillation which is dominant in the remaining 10-20ps rms jitter between the transmitted
pulses and the RF reference generator.
10ps rms jitter is equivalent to phase jitter dphi = 2*pi*f0*dt = 2mrad rms @ 33MHz or 30mrad rms @ 500MHz. |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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what does this 10ps phase jitter mean in term of cavity length variations ?
L = L0 + dL sin(2pi fm t) = L0 (1 + dL/L0 sin(2pi fm t))
F = c / L ~ F0 - F0² dL / c sin(2pi fm t) with F0 = c / L0 |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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measure to be done next week to check the 20Hz noise on the laser amplifier signal:
- install a DET10 in reflection of the FP-cavity to get a high BW and measure the 500MHz harmonic.
- do the beating with the 500MHz Ring RF generator |
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20Hz oscillation in the locking between Laser and FP-cavity, posted by Ronic Chiche at ThomX igloo about mechanics | lasers and optics | detectors and electronics
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could it be possible this 20Hz oscillations comes from anouncements in the bunker, puting the housing+table in vibration ?
(there are such anouncements during restricted access) => to be asked to Harold
Ronic |
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fixing CVBG issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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the CVBG of the compressor module seems to have an issue.
here is the plan of the work :
1) faire des résonances avec la CFP |
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fixing CVBG issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics 12x
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1) this morning, I aligned to CFP to get back 82kW in the cavity for 33% of amplifier ratio.
thus, we can ajust the iris positions on the optical table to fix the CFP optical path before touching the CVBG.
2) we aligned the 5 iris. all of them were misaligned by 1-2mm, principaly vertically (maybe because we had to change the CFP frequency some |
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fixing CVBG issue, posted by Ronic Chiche at ThomX igloo about lasers and optics | detectors and electronics
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this morning with Daniele, we realigned the amplifier beam axis on the iris position.
it was pretty fast an easy => we got rapidely some resonance and we locked back to 87kW @33% amp ratio after tuning CEP and alignment.
we tried to play on the L-shape but we didn't a clear effect. |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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on Monday morning 7/11, we tried to restart the Alphanov amplifier which was not turned on since end of april 2022, but it didn't start.
we did a standard "turn ON" procedure :
- check the safety button on the front panel (which has to be released). |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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I just tested the fuse inside the black ON/OFF switch on the rear panel => it is OK ! :-(
Ronic
Chiche wrote:
on Monday morning 7/11, we tried to restart the Alphanov amplifier |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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The laser amplifier controller has been sent yesterday and received today by Alphannov.
they should do the assessment quickly...
Ronic |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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Today, I did a Teams meeting with Guillaume.
He didn't see any problem with the controller.
normally, the controller will be shipped to the lab tomorrow. |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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Yesterday, we received the controller back from Alphanov
and I tested it immediately in the optical room.
if the software is properly talking to the controller, everything works normally. |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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FYI : to access special menus on the Alphanov software,
login : "Administrator"
pwd : no password |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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the present situation is :
Guillaume asked me to disconnect the "Laser head" cable from the pump diode module, installed on the optical table.
on the pump diode module, the connector has several small pins and 3 larges pins : A1, A2, A3. |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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Guillaume and Julien Bour from Alphanov will come on wednesday 24/07 to have a first look and check the amplifier.
to prepare their intervention, I tested this morning the OneFive oscillator : it's still working at 33MHz.
and we have ~5mW in the LAL software without the EOM. |
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Alphanov amplifier issue, posted by Ronic Chiche at ThomX igloo about lasers and optics
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picture of the connectors used to carry signals between the amplifier pump module and the rack under the table.
DB13W3 standard has been used to carry high current on the 3 dedicated pins:
https://en.wikipedia.org/wiki/DB13W3 |
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New password for login on the ThomX computer, posted by Ronic Chiche at ThomX igloo about software
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the previous password has expired.
the new access from the computer :
login : .\$jehanno |