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ID Date Author Type Categoryup Subject Text Attachments
  861   Sat Mar 3 17:50:45 2012 taraDailyProgressBEATbeat is backNO!! no dance
party for you because you didn't return our
  862   Sat Mar 3 18:07:15 2012 ZachDailyProgressBEATbeat is backAnd I stole one of your air dusters :-)
There used to be TWO label makers
in the ATF---one of which looked like that
  863   Sun Mar 4 00:45:26 2012 frank, taraDailyProgressBEATbeat is backBeat is back.
The beat signal( with the new softer
springs) is measured and compared with the
  864   Mon Mar 5 16:29:50 2012 frank, taraDailyProgressBEATbeat is backAs mentioned in the previous entry that
the in loop noise is higher than before.
We investigate what might be the causes.
  870   Tue Mar 6 20:48:47 2012 frank, taraDailyProgressBEATbeat is backAfter debugging the RCAV loop, we measured
the beat signal again.  We still cannot
reach coating thermal noise, the noise floor
  878   Sat Mar 10 18:42:42 2012 taraDailyProgressBEATbeat- with air spring isolation  Beat measurement with new air springs
is measured with unfloated table (the N2
supply is empty). Good improvement can be
  882   Mon Mar 12 23:31:38 2012 frank, taraDailyProgressBEATbeat with floated table, air spring.We measured beat signal with the upgraded
seismic isolation system. It seems that we
are sitting on some scattering noise source
  900   Fri Apr 6 01:03:01 2012 frank, taraDailyProgressBEATground loop problemWe fixed the ground loop problem in ACAV
setup and got rid of most of the harmonic
lines in beat signal. 
  929   Sat Apr 21 00:55:00 2012 frank, taraDailyProgressBEATBeat measurement updateWe measured the beat after a few changes
in the setup (modulation index, air spring,
small enclosure around the beat). We update
  946   Fri Apr 27 22:37:54 2012 taraDailyProgressBEATreplacing one mirror mount in beat pathOne of the mirror mount in beat path was
not properly mounted on the board because
of the limited space. I changed that mirror
  947   Mon Apr 30 01:41:18 2012 taraDailyProgressBEATnoise due to air leaking from legsI suspected that the air leaking from the
legs might cause  noise in acoustic
bandwidth, so I measured the beat signal
  966   Fri May 18 03:56:22 2012 taraDailyProgressBEATbeat measurement updateThe beat signal is getting better at lower
frequency, there is no obvious scattering
bump around 80 Hz anymore. It is possible
  967   Fri May 18 18:44:38 2012 taraDailyProgressBEATbeat measurement updateI'm trying to fix the mechanical peaks
in the beat signal. The work is still in
  978   Mon Jun 4 22:38:44 2012 taraDailyProgressBEATlow frequency beat with 32kHz ADCI tried to measure beat signal without
using PLL, the FFT of the demodulated signal
does not look good. We probably need to do
  980   Tue Jun 5 23:30:47 2012 ranaDailyProgressBEATlow frequency beat with 32kHz ADC


  990   Tue Jun 19 00:08:19 2012 taraDailyProgressBEATlow frequency beat with 32kHz ADCI'm using simulink to do software PLL. 
As Zach suggested that using simulink
to do the PLL might be easier than using
  991   Wed Jun 20 16:06:50 2012 taraDailyProgressBEATlow frequency beat with 32kHz ADCKoji suggested I try to measure the frequency
noise of the demodulated beat this way. By
using I and Q signals of the demodulated
  992   Wed Jun 20 17:50:59 2012 ranaDailyProgressBEATlow frequency beat with 32kHz ADC This is overdoing it. Please just
post the existing beat data somewhere and
I can show you how to do it easily with a
  993   Wed Jun 20 20:48:16 2012 SarahDailyProgressBEATfrequency noise of demodulated beat To avoid doing PLL with Simulink,
Tara and I measured the Q and I signals for
the demodulated beat frequency to measure
  994   Thu Jun 21 16:04:39 2012 taraDailyProgressBEATlow frequency beat with 32kHz ADC

  995   Fri Jun 22 03:35:54 2012 taraDailyProgressBEATfrequency noise of demodulated beatI added the result from the I-Q measurement
method in PSL:993.
  1009   Sat Jun 30 05:01:04 2012 taraDailyProgressBEATbeat measurement with 2mW input powerI changed the power input from 1mW to
2mW for both cavities and measure the beat
signal. From the measured results, there
  1039   Fri Aug 10 19:50:37 2012 taraDailyProgressBEATcode schmidtt trigger for beat I used Schmidtt trigger process to track
frequency of beat measurement. This is a
first step for digital PLL.
  1041   Thu Aug 30 02:52:01 2012 taraDailyProgressBEATcode schmidtt trigger for beat I'm trying to check if the schmidtt trigger
algorithm will work as our beat readout or
not (observe beat from dc to 1kHz), I also
  1042   Fri Aug 31 00:48:00 2012 taraDailyProgressBEATcode schmidtt trigger for beat  I compared results from three different
readout techniques, it seems that my Schmidtt
algorithm does not work at frequency above
  1043   Mon Sep 3 01:02:46 2012 taraDailyProgressBEATcode schmidtt trigger for beat I used IQ readout method to measure the
frequency noise of Marconi. The sensitivity
was good, it was lower than 10^-3 Hz/rtHz
  1115   Tue Mar 12 20:51:00 2013 ranaNotesBEATMode matching plan for beat breadboard 
 Its good that the beams can
be matched, but there are a few more considerations
  1229   Tue Jul 9 14:47:44 2013 EricaNotesBEATWriting progress reportJuly 7, 2013
Took pictures of the setups for mode matching
and recombining the beams.  I added beam
  1256   Fri Jul 26 11:07:44 2013 EricaDailyProgressBEATcircuit for measuring temperature fluctations on CTN tableJuly 23, 2013
Went to a lecture Alan gave for the CGWAS
on data analysis in the morning at Cahill
  1257   Fri Jul 26 11:22:45 2013 EricaDailyProgressBEATcircuit for measuring temperature fluctations on CTN tableJuly 24, 2013

Took the tour to JPL today.  Got to see the
  1258   Fri Jul 26 11:45:28 2013 EricaDailyProgressBEATcircuit for measuring temperature fluctations on CTN tableJuly 25, 2013

finished building the circuit today.  Had
  1261   Mon Jul 29 13:30:26 2013 EricaDailyProgressBEATadding resistor, capacitor, and socketsJuly 26, 2013

Was able to place the 24k ohm resistor in
  1265   Tue Jul 30 12:23:41 2013 EricaDailyProgressBEATaddressed noise problem, DC signaljuly 29, 2913

Worked on progress report due Friday.
  1274   Thu Aug 1 21:19:57 2013 taraDailyProgressBEATsearching for beatI locked both cavities and trying to search
for the beat signal, I have not succeeded
  1275   Fri Aug 2 12:18:16 2013 taraDailyProgressBEATsearching for beatFound the beat @ 116 MHz. RCAV SLOW =5.762V,
ACAV SLOW = 1.209 V. 
  1305   Fri Aug 16 22:05:27 2013 taraDailyProgressBEATnoise hunting Noise hunting is in progress, I checked
the error noise from ACAV and RCAV loops
and compared them to the beat. The beat is
  1307   Tue Aug 20 20:10:01 2013 taraDailyProgressBEATnoise huntingNoise hunting is in progress. Today I identified
that scattered light from the window is one
of the problem.
  1316   Wed Aug 28 11:13:07 2013 EvanDailyProgressBEATIntensity-to-frequency transfer function[Tara, Evan]
Last week we tried measuring a transfer
function which takes intensity fluctuation
  1361   Tue Oct 8 23:01:56 2013 EvanDailyProgressBEATAttempts at new beat measurement[Tara, Evan]
Having successfully floated the table
yesterday, we attempted a new beat measurement
  1368   Thu Oct 17 21:50:28 2013 EvanDailyProgressBEATNew intensity-to-frequency TF[Tara, Evan]
We took another RIN-to-beat transfer
function, as in PSL:1316.
  1369   Mon Oct 21 14:04:04 2013 ranaDailyProgressBEATNew intensity-to-frequency TF Even though it shouldn't be there,
there is probably a coupling directly from
RIN to the reflected PDH signal on each cavity.
  1373   Sat Oct 26 15:35:42 2013 EvanDailyProgressBEATBeat measurement with ISSSummary: No good so far. Engaging
the ISS seems to have basically zero effect
on the beat. The beat overall looks     
  1375   Mon Oct 28 22:55:11 2013 EvanDailyProgressBEATBeat measurement with ISSI've taken Tara's farsi.m and changed
the values of finesse F and absorption
  1382   Tue Nov 5 10:34:09 2013 EvanDailyProgressBEATNew beat measurement[Tara, Evan]
Yesterday, we did a few final bits
of optimization and then re-measured the
  1438   Thu Jun 26 17:10:09 2014 EvanDailyProgressBEATBeatSouth laser slow at 1.234 V, north laser
slow at 5.558 V, beat is 120(1) MHz at +5.5(2)
dBm. South and north alignment has not yet
  1447   Wed Jul 9 22:31:59 2014 Emily, EvanNotesBEATfiber phase noise measurement Installation of optics for fiber phase
noise measurement
After light passes through the AOM,
  1492   Fri Aug 29 12:35:54 2014 EvanDailyProgressBEATBeat breadboard in placeBeat breadboard is slid back into place.
North transmission appears on north camera.
Still need to do south transmission.
  1493   Fri Aug 29 15:35:55 2014 EvanDailyProgressBEATMode-matching for beatI predict (via alm) that the spot size
on the diode (z = 991 mm) is 79 µm
in the current configuration.
  1494   Fri Aug 29 19:56:06 2014 EvanDailyProgressBEATBeat breadboard in place


  1496   Tue Sep 2 11:06:54 2014 EvanDailyProgressBEATNo beatSearched around over various axial modes
in order to find a beat.
I fiddled a bit with the output QWPs
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