ID |
Date |
Author |
Type |
Category |
Subject |
1832
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Wed Aug 5 09:25:57 2009 |
Alberto | DAQ | Computers | fb40m is up |
FB40m up and running again after restarting the DAQ. |
1836
|
Wed Aug 5 15:33:05 2009 |
rob, alberto | DAQ | General | can't get trends |
We can't read minute trends from either Dataviewer or loadLIGOData from before 11am this morning.
fb:/frames>du -skh minute-trend-frames/
106G minute-trend-frames
So the frames are still on the disk. We just can't get them with our usual tools (NDS).
Trying to read 60 days of minute trends from C1:PSL-PMC_TRANSPD yields:
Connecting to NDS Server fb40m (TCP port 8088)
Connecting.... done
258.0 minutes of trend displayed
read(); errno=9
read(); errno=9
T0=09-06-06-22-34-02; Length=5184000 (s)
No data output.
Trying to read 3 seconds of full data works.
Second trends are readable after about 4am UTC this morning, which is about 9 pm last night.
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1841
|
Thu Aug 6 09:22:17 2009 |
Alberto | DAQ | General | can't get trends |
Quote: |
We can't read minute trends from either Dataviewer or loadLIGOData from before 11am this morning.
fb:/frames>du -skh minute-trend-frames/
106G minute-trend-frames
So the frames are still on the disk. We just can't get them with our usual tools (NDS).
Trying to read 60 days of minute trends from C1:PSL-PMC_TRANSPD yields:
Connecting to NDS Server fb40m (TCP port 8088)
Connecting.... done
258.0 minutes of trend displayed
read(); errno=9
read(); errno=9
T0=09-06-06-22-34-02; Length=5184000 (s)
No data output.
Trying to read 3 seconds of full data works.
Second trends are readable after about 4am UTC this morning, which is about 9 pm last night.
|
Yesterday Alex started transferring the data records to the new storage unit. That prevented us from accessing the trends for a fe hours.
The process had been completed and now we can read the trends again. |
2365
|
Tue Dec 8 10:20:33 2009 |
Alberto | DAQ | Computers | Bootfest succesfully completed |
Alberto, Kiwamu, Koji,
this morning we found the RFM network and all the front-ends down.
To fix the problem, we first tried a soft strategy, that is, we tried to restart CODAQCTRL and C1DCUEPICS alone, but it didn't work.
We then went for a big bootfest. We first powered off fb40m, C1DCUEPICS, CODAQCTRL, reset the RFM Network switch. Then we rebooted them in the same order in which we turned them off.
Then we power cycled and restarted all the front-ends.
Finally we restored all the burt snapshots to Monday Dec 7th at 20:00. |
2874
|
Mon May 3 19:21:43 2010 |
Alberto | DAQ | Environment | Boot fest |
[Alberto, Koji, Rana]
The RFM network failed today. We had to reboot the frame builder anf restart all the front end following the instructions for the "Nuclear Option".
Burt-restoring to May 1st at 18:07, or April 30 18:07 made c1sosvme crash. We had to reset the front ends again and restore to April 15th at 18:07 in order to make everything work.
Everything seems fine again now. |
3038
|
Wed Jun 2 18:36:20 2010 |
valera | DAQ | CDS | Noise generators in LSP |
Alex wrote a new code to implement LSP noise generator. The code is based on 64 bit random number generator from Numerical Recipes 3rd ed ch 7.1 (p 343).
Joe made two instances in the LSP model.
The attached plot shows the spectra and coherence of two generators. The incoherence is ~1/Navg - statistically consistent with no coherence. |
Attachment 1: noisegenerators.pdf
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3090
|
Sat Jun 19 17:31:48 2010 |
rana | DAQ | CDS | Excess Noise in C1:IOO-MC_DRUM1 fixed by reboot |
I was getting an excess noise in the C1:IOO-MC_DRUM1 channel - it was a flat spectrum of 10 cts/rHz (corresponding to 600 uV/rHz).
I tried a few things, but eventually had to power cycle the crate with c1iovme in order to recover the standard ADC noise level of 3x10^-3 cts/rHz with a 1/sqrt(f) knee at 10 Hz.
I checked the gain of the channel by injecting a 2 Vpp sine wave at 137.035 Hz. 2Vpp as measured on a scope gives 31919 cts instead of the expected 32768, giving a 2.5% error from what we would have naively calculated.
Even so, the noise in this channel is very surprisingly good: 0.003 / (31919 / 2) = 187 nV /rHz. The best noise I have previously seen from an ICS-110B channel is 800 nV/rHz. What's going on here? |
3117
|
Thu Jun 24 18:47:26 2010 |
Frank | DAQ | IOO | VME crate rebooted |
we had to reboot the IOO VME crate right before lunch as the DAQ wasn't working correct meaning showing no real signals anymore, only strange noise. The framebuilder and everything else was working fine at that time.
- The channel used for the phase noise measurement stopped showing any useful signal right after midnight, so all the other IOO-MC signals.
- The data taken with those channels showed something like a 140 counts or so of steady offset with something which looked like the last bit fluctuating.
- Whatever signal we connected to the input it didn't change at all, floating/shorted input, sine wave etc.
- the other channels for the MC which we checked showed the same strange behaviour
As the other channels showed the same effect we decided to reboot the crate and everything was fine afterwards. |
173
|
Thu Dec 6 15:21:59 2007 |
alberto | Frogs | Electronics | RF Transfer Function of Stiff Aluminum Wires |
Transfer function of 3cm long Aluminum wires and of 3cm stranded wires |
Attachment 1: TF_3cm_stiff_wires.amplitude.png
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Attachment 2: DSC_0225compressed.JPG
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Attachment 3: TF_3cm_stranded_wires.amplitude.png
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189
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Wed Dec 12 22:24:48 2007 |
tobin | Frogs | PEM | weather station |
I poked at the weather station briefly this evening.
* There's almost nothing in the elog about it.
* It exists. It is located on the North wall, just north of the beam splitter.
* It seems to be displaying reasonable data for the indoors, but nothing for the outdoor sensors.
* c1pem didn't seem to be starting up (couldn't telnet into it, etc). I altered its startup file and reset it several times, and eventually it came to life.
* the weather station has a serial cable that goes all the way to c1pem. I plugged it in.
* however, the Weather.st program complains "NO COMM"--it gets no data from the weather station
* The next thing to do is to plug in a laptop to that serial cable and see if the weather station can be convinced to talk. |
340
|
Sun Feb 24 10:51:58 2008 |
tf | Frogs | Environment | 40m in phdcomics? |
 |
581
|
Fri Jun 27 09:20:15 2008 |
steve | Frogs | PEM | dust particle count is up & alarm handler is on |
This 3 years plot show the trend of seasons.
When outside air quality goes bad ( 0.5 micron > 1 million ) the lab follows.
I will demonstrate this effect with a 4th of July fire works calibration.
Let's do not forget the construction activity next door either.
The alarm handler is busy:
It's sound level were reset to a modest level yesterday.
It would be nice to change the alarm sound so it can play Wagner:Der Ring des Nibelungen:
Das Rheingold, Die Walkure & Siegfried and Gotterdammerung
or something more appropriate than the present frog call
1, half micron count is climbing ( it's close to 16k now )
2, MZ refl signal is too high
3, MC lenght servo LO is too |
Attachment 1: dust3y.jpg
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666
|
Mon Jul 14 10:57:00 2008 |
Koji | Frogs | Environment | Someone at 40M sent LHO water of life |
Someone at the 40m sent Mike@LHO a pound of peets coffee with the name of Koji Arai.
It was a good surprise! Thanks, we will enjoy it!
I will return to Pasadena next week. See you then. |
877
|
Mon Aug 25 11:43:55 2008 |
Yoichi | Frogs | IOO | MC REFL PD cable had been disconnected through out the weekend |
Most of my morning was wasted by the MC REFL PD cable, which was disconnected on the generic LSC PD interface board.
I know who did this. *ME*. When I pulled out the MC board, which is sitting next to the PD interface, on Friday, I must have
disconnected the PD cable accidentally. The connector of the PD cable (D-Sub) does not have screws to tighten and easily comes off.
I wrote this entry to warn other people of this potential problem. |
976
|
Mon Sep 22 15:02:45 2008 |
rana | Frogs | Treasure | Mantis found outside the 40m door at night |
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Attachment 1: mantis.JPG
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1268
|
Tue Feb 3 15:01:38 2009 |
Alberto | Frogs | Computers | megatron slow? |
I notice that Megatron is slower than any other computer in running code that invokes optickle or looptickle (i.e. three times slower than Ottavia). Even without the graphics.
Has anyone ever experienced that? |
1275
|
Thu Feb 5 16:21:07 2009 |
Jenne | Frogs | Computers | Belladonna connects to the wireless Martian network again |
Symptoms: Belladonna could not (for a while) connect to the wireless network, since there was a driver problem for the wireless card. This (I believe) started when Yoichi was doing updates on it a while back.
The system: Belladonna is a Dell Inspirion E1505 laptop, with a Broadcom Corporation Dell Wireless 1390 WLAN Mini-PCI Card (rev 01)
Result: Belladonna now can talk to it's wireless card, and is connected to the Martian network. (MEDM and Dataviewer both work, so it must be on the network.)
What I did:
0. Find a linux forum with the following method: http://www.thelinuxpimp.com/main/index.php?name=News&file=article&sid=749
The person who wrote this has the exact same laptop, with the same wireless card.
1. Get a new(er) version of ndiswrapper, which "translates" the Windows Driver for the wireless card to Linux-ese. Belladonna previously was using ndiswrapper-1.37.
$wget http://nchc.dl.sourceforge.net/sourceforge/ndiswrapper/ndiswrapper-1.42.tar.gz
2. Put the ndiswrapper in /home/controls/Drivers, and installed it.
$ndiswrapper -i bcmwl5.inf 3. Get and put the Windows driver in /home/controls/Drivers/WiFi
$wget http://ftp.us.dell.com/network/R140747.EXE
4. Unzip the driver
$unzip -a R140747.EXE
5. Make Fedora use ndiswrapper
$ndiswrapper -m
$modprobe ndiswrapper
6. Change some files to make everything work:
/etc/sysconfig/wpa_supplicant CHANGE FROM: DRIVERS="-Dndiswrapper" CHANGE TO: DRIVERS="-Dwext"
/etc/sysconfig/network-scripts/ifcfg-wlan0 CHANGE FROM: BOOTPROTO=none CHANGE TO: BOOTPROTO=dhcp
/etc/rc.d/init.d/wpa_supplicant CHANGE FROM: daemon $prog -c $conf $INTERFACES $DRIVERS -B CHANGE TO: daemon $prog -c$conf $INTERFACES $DRIVERS -B
6. Restart things
$service wpa_supplicant restart
$service network restart
7. Restart computer (since it wasn't working after 1-6, so give a restart a try)
8. Success!!! MEDM and Dataviewer work without any wired internet connection => wireless card is all good again!
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1479
|
Mon Apr 13 18:57:03 2009 |
Alberto | Frogs | Computers | GPIB/ETH Interface Troubles |
I really don't understand why my programs that I used to use to get data from the HP Spectrum Analyzer and the Marconi frequency generator don't work anymore.
I spent hours trying to debug the code but I can't sort the problem out.
The main problem seem to be with the function recv from the socket library. Somehow it can't anymore get any data from the instruments. The thing I can't understand, though, is that if called directly from the python terminal it works fine!
In particular the problem is with the following lines in my code:
netSock.send("mkpk;mka?\n")
netSock.send("++read eoi\n")
tmp = netSock.recv(1024)
Tried a lot of tickering but it didn't work.
I attach the two scripts I've been using. One (sweepfrequencyPRC.py) calls the other (HP4395PRC.py).
They worked egregiously for weeks in the past. Don't know what happened since then. |
Attachment 1: sweepfrequencyPRC.py
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## sweepfrequency.py [-f filename] [-i ip_address] [-a startFreq] [-z endFreq] [-s stepFreq] [-m numAvg]
#
## This script sweeps the frequency of a Marconi local oscillator, within the range
## delimited by startFreq and endFreq, with a step set by stepFreq. An arbitary
## signal is monitored on a HP8590 spectrum analyzer and the scripts records the
## amplitude of the spectrum at the frequency injected by the Marconi at the moment.
## The GPIB address of the Marconi is assumed to be 17, that of the HP Spectrum Analyzer to be 18
## Alberto Stochino, October 2008
... 53 more lines ...
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Attachment 2: HP8590PRC.py
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# This function provides the measuremeent of the peak amplitude on the spectrum analyzer
# HP8590 analyzer while sweeping the excitation frequency on the function generator.
#
# Alberto Stochino 2008
import re
import sys
import math
from optparse import OptionParser
from socket import *
... 70 more lines ...
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1481
|
Tue Apr 14 12:10:11 2009 |
Alberto | Frogs | Computers | GPIB/ETH Interface Troubles |
Quote: |
I really don't understand why my programs that I used to use to get data from the HP Spectrum Analyzer and the Marconi frequency generator don't work anymore.
I spent hours trying to debug the code but I can't sort the problem out.
The main problem seem to be with the function recv from the socket library. Somehow it can't anymore get any data from the instruments. The thing I can't understand, though, is that if called directly from the python terminal it works fine!
In particular the problem is with the following lines in my code:
netSock.send("mkpk;mka?\n")
netSock.send("++read eoi\n")
tmp = netSock.recv(1024)
Tried a lot of tickering but it didn't work.
I attach the two scripts I've been using. One (sweepfrequencyPRC.py) calls the other (HP4395PRC.py).
They worked egregiously for weeks in the past. Don't know what happened since then.
|
This morning Joe looked at my code and made me notice that for some reason the query to the Spectrum Analyzer made by netSock.recv(1024) contained two answers. It was like the buffer contained the answer two different queries.
After some experiment I found that basically the GPIB interface wasn't switching from the "auto 1" to the "auto 0" mode as it should. I rewrote part of the code and that seemed have solved the problem.
Still don't understand why it used to work in the past and then it stopped. |
1911
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Sat Aug 15 18:35:14 2009 |
Clara | Frogs | Computers | How far back is complete data really saved? (or, is the cake a lie?) |
I was told that, as of last weekend, we now have the capability to save full data for a month, whereas before it was something like 3 days. However, my attempts to get the data from the accidentally-shorted EW2 channel in the Guralp box have all been epic failures. My other data is okay, despite my not saving it for several days after it was recorded. So, my question is, how long can the data actually be saved, and when did the saving capability change? |
2049
|
Mon Oct 5 09:31:05 2009 |
Alberto | Frogs | PSL | PSL laser accidentally turned off |
Alberto, Steve,
While I was moving a cart near by the PSL table I pushed the red emergency button that turns off the PSL laser. We had to unlock the button and then power cycle the laser driver to turn the laser back on.
I relocked MZ, FSS, PMC and I'm now waiting for the power to finish ramping up back to the previous value. |
2219
|
Mon Nov 9 16:32:36 2009 |
Alberto | Frogs | Environment | Shot of the white board yesterday before erasing |
Yesterday Rana and I needed some room on the white board in the Control Room. We had to erase some of the stuff present on the board despite the bif warning "Do Not Erase".
This is how it looked like before erasing.

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Attachment 1: DSC_0980.JPG
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2220
|
Mon Nov 9 18:27:30 2009 |
Alberto | Frogs | Computers | OMC DCPD Interface Box Disconnected from the power Supply |
This afternoon I inadvertently disconnected one of the power cables coming from the power supply on the floor next to the OMC cabinet and going to the DCPD Interface Box.
Rob reconnected the cable as it was before. |
2236
|
Wed Nov 11 12:29:44 2009 |
Alberto | Frogs | PSL | MC Locked on the wrong mode? |
This morning, after Steve pointed out that the readout RFAMPD_DC was zero, I thought of realigning the beam on the photodiode. Maybe I touched the lens or the beam splitter that send the beam on the diode when I installed an other beam splitter to make the measurement of the calibration between two ThorLabs PDA255 photodiodes.
After aligning the beam on the RFAMPD, the voltage of the DC readout was lower than it used to be (C1:IOO-RFAMPD_DC ~ 0.4 now vs. 4 as it was on November 4th).
I maximized the DC readout but the problem seems to be that the beam spot is not a round TEM00. In particular the spot looks like that of a TEM10 mode.
Since we're looking at the MC transmitted beam, is it possible that the MC is locked on the wrong mode?
Check out the attached picture. |
Attachment 1: PB110184-1.JPG
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2296
|
Thu Nov 19 08:53:12 2009 |
pete | Frogs | Environment | diesel fumes |
Instead of doing RCG stuff, I went to Millikan to work on data analysis as I couldn't stand the fumes from the construction. (this morning, 8am) |
2377
|
Thu Dec 10 08:43:25 2009 |
steve | Frogs | Environment | diesel fumes are less |
Quote: |
Instead of doing RCG stuff, I went to Millikan to work on data analysis as I couldn't stand the fumes from the construction. (this morning, 8am)
|
Diesel fumes are pumped away from control room AC intakes with the help of newly installed reflector boxes on the CES wall fans.........see # 2272 |
Attachment 1: P1050817.JPG
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2560
|
Tue Feb 2 15:30:03 2010 |
Alberto | Frogs | Treasure | Wild Oats |
FYI. Sitting on the top shelf of George I found an opened jar of raspberry jam and an opened jar of creamy peanut butter. Both are branded Wild Oats Market.
Wikipedia:
"Wild Oats Markets was an operator of natural foods stores and farmers markets in North America... Whole Foods officially completed their buyout of Wild Oats on August 27, 2007 [...]" |
3004
|
Fri May 28 07:13:05 2010 |
Alberto | Frogs | Green Locking | SR785 found abandoned next to the workbenches |
A poor lonely SR785 was found this morning roaming around in the lab in evident violation of the fundamental rule which requires all the equipment on carts to be brought back inside the lab right after use.
The people and the professors related to the case should take immediate action to repair for their misdeed. |
3131
|
Tue Jun 29 08:55:18 2010 |
Jenne | Frogs | Environment | We're being attacked! |

We're going to have to reinstate the policy of No food / organic trash *anywhere* in the 40m. Everyone has been pretty good, keeping the food trash to the one can right next to the sink, but that is no longer sufficient, since we've been invaded by an army of ants:

We are going back to the old policy of Take your trash out to the dumpsters outside. I'm sure there are some old wives tales about how exercise after eating helps your digestion, or something like that, so no more laziness allowed! |
3421
|
Fri Aug 13 15:29:35 2010 |
Aidan | Frogs | Photos | Here's the 40m team |
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Attachment 1: 40m_team.JPG
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3424
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Mon Aug 16 13:33:06 2010 |
Zach | Frogs | Photos | Here's the 40m team |
One day I'll get to be part of the krew |
3512
|
Thu Sep 2 01:48:23 2010 |
Jenne | Frogs | Treasure | Not cool.... |
This totally creeped me out when I found it wandering around on the floor not so far from my desk:

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3520
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Fri Sep 3 11:03:41 2010 |
Alberto | Frogs | Electronics | Cable cutting tools |
I found this very interesting German maker of cool cable cutting tools. It's called Jokari.
We should keep it as a reference for the future if we want to buy something like that, ie RF coax cable cutting knives.
http://www.jokari.de/en.htm |
3522
|
Fri Sep 3 13:04:30 2010 |
Koji | Frogs | Electronics | Cable cutting tools |
Yeah, this looks nice.
And I also like to have something I have attached. This is "HOZAN P-90", but we should investigate American ones
so that we can cut the wires classified by AWG.
Quote: |
I found this very interesting German maker of cool cable cutting tools. It's called Jokari.
We should keep it as a reference for the future if we want to buy something like that, ie RF coax cable cutting knives.
http://www.jokari.de/en.htm
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Attachment 1: P90.jpg
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3598
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Thu Sep 23 10:34:20 2010 |
rana | Frogs | Computers | nodus gracefully rebooted |
SVN down
mafalda down
I am guessing that the NFS file system hangup may have caused some machines to get into an awkward state. We may be best off doing a controlled power cycle of everything... |
3599
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Thu Sep 23 11:15:20 2010 |
Koji | Frogs | Computers | nodus gracefully rebooted |
svn is back after starting apache on nodus.
http://lhocds.ligo-wa.caltech.edu:8000/40m/ApacheOnNodus
Quote: |
SVN down
mafalda down
I am guessing that the NFS file system hangup may have caused some machines to get into an awkward state. We may be best off doing a controlled power cycle of everything...
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3601
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Thu Sep 23 13:16:57 2010 |
Koji | Frogs | Computers | nodus gracefully rebooted |
mafalda is up now.
I found that the cable for mafalda (the sole red cable) had a broken latch.
The cable was about falling off from the switch. As a first-aid, I used this technique to put a new latch, and put it into the switch.
Now I can logged in it. I did not rebooted it.
Quote: |
SVN down
mafalda down
I am guessing that the NFS file system hangup may have caused some machines to get into an awkward state. We may be best off doing a controlled power cycle of everything...
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3682
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Fri Oct 8 17:36:16 2010 |
steve | Frogs | Photos | visiting undergrads |
Prof Alan Weistein guided the 24 student through the 40m. His performance was rated as an enthusiastic 9.5 |
Attachment 1: P1060916.JPG
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Attachment 2: P1060921.JPG
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Attachment 3: P1060922.JPG
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Attachment 4: P1060915.JPG
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4319
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Thu Feb 17 23:41:46 2011 |
rana | Frogs | DAQ | Frames Directory got the wrong name: Data unreachable |
DTT stopped working for recent data. An 'ls' in the frames/full/ directory reveals:
drwxr-xr-x 2 controls controls 258048 Feb 3 12:26 9807
drwxr-xr-x 2 controls controls 258048 Feb 4 16:13 9808
drwxr-xr-x 2 controls controls 262144 Feb 5 19:59 9809
drwxr-xr-x 2 controls controls 258048 Feb 6 23:46 9810
drwxr-xr-x 2 controls controls 258048 Feb 8 03:33 9811
drwxr-xr-x 2 controls controls 262144 Feb 9 07:19 9812
drwxr-xr-x 2 controls controls 253952 Feb 10 11:06 9813
drwxr-xr-x 2 controls controls 266240 Feb 11 14:53 9814
drwxr-xr-x 2 controls controls 266240 Feb 12 18:39 9815
drwxr-xr-x 2 controls controls 266240 Feb 13 22:26 9816
drwxr-xr-x 2 controls controls 262144 Feb 15 02:13 9817
drwxr-xr-x 2 controls controls 253952 Feb 16 05:59 9818
drwxr-xr-x 2 controls controls 241664 Feb 17 09:46 9819
drwxr-xr-x 2 controls controls 28672 Feb 17 12:22 9820
drwxr-xr-x 2 controls controls 32768 Feb 17 15:06 6663
drwxr-xr-x 2 controls controls 73728 Feb 17 23:39 6664
controls@fb /frames/full $ date
Thu Feb 17 23:39:27 PST 2011
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4442
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Fri Mar 25 01:27:29 2011 |
mevans | Frogs | Green Locking | digital frequency counting |
Today we tried the Schmitt trigger DFD, and while it works it does not improve the noise performance. At least part of our problem is coming from the discrete nature of our DFD algorithm, so I would propose that an industrious day job person codes up a new DFD which avoids switching. We can probably do this by mixing the input signal (after high-passing) with a time-delayed copy of itself... as we do now, but without the comparator. This has the disadvantage of giving an amplitude dependent output, but since we are working in the digital land we can DIVIDE. If we mix the signal with itself (without delay) to get a rectified version, and low-pass it a little, we can use this for normalization. The net result should be something like:
output = LP2[ s(t) * s(t - dt) / LP1[ s(t) * s(t) ]],
where s(t) is the high-passed input and LP is a low-pass filter. Remember not to divide by zero.
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4444
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Fri Mar 25 11:16:19 2011 |
josephb | Frogs | Green Locking | digital frequency counting |
I modified the c1gfd.mdl simulink model. I made a backup as c1gfd_20110325.mdl.
The first change was to use a top_names block to put everything in. The block is labeled ALS. So all the channels will now be C1:ALS-GFD_SOMETHING. This means medm channel names will need to be updated. Also, the filter modules need to be updated in foton because of this.
I then proceeded to add the suggested changes made by Matt. To avoid a divide by zero case, I added a saturation part which saturates at 1e-9 (note this is positive) and 1e9.
Quote: |
Today we tried the Schmitt trigger DFD, and while it works it does not improve the noise performance. At least part of our problem is coming from the discrete nature of our DFD algorithm, so I would propose that an industrious day job person codes up a new DFD which avoids switching. We can probably do this by mixing the input signal (after high-passing) with a time-delayed copy of itself... as we do now, but without the comparator. This has the disadvantage of giving an amplitude dependent output, but since we are working in the digital land we can DIVIDE. If we mix the signal with itself (without delay) to get a rectified version, and low-pass it a little, we can use this for normalization. The net result should be something like:
output = LP2[ s(t) * s(t - dt) / LP1[ s(t) * s(t) ]],
where s(t) is the high-passed input and LP is a low-pass filter. Remember not to divide by zero.
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Attachment 1: C1GFD.png
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4447
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Mon Mar 28 16:19:23 2011 |
steve | Frogs | Photos | visithing 5th graders |
Suresh is captivating his audience with gravity waves on last Friday, March 25 |
Attachment 1: P1070475.JPG
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4597
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Mon May 2 13:43:05 2011 |
steve | Frogs | Photos | birthday boys |
.....Happy.... Birthday.... to.... Joseph... and... Jamie...Happy....Birthday..... to.... You............sing with us........Happy Birthday.....to you |
Attachment 1: P1070622.JPG
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4615
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Tue May 3 15:59:22 2011 |
steve | Frogs | Photos | X-mas comes early |
The little red all terrain cargo wagon 40" x 18" has just arrived on pneumatic wheels.
Model #29, 200 lbs max load at 26 PSI, minimum age requirement 1.5 years |
Attachment 1: P1070634.JPG
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5020
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Fri Jul 22 17:01:41 2011 |
Iron Man | Frogs | General | Proof that Alberto lived through his Iron Man! |
 
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208 |
Alberto |
Stochino |
67/129 |
585/1376 |
36:02 |
1:52 |
830 |
6:41 |
2:38:58 |
21.1 |
296 |
4:58 |
56:33 |
2:13:40 |
- |
5:40:19 |
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7758
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Wed Nov 28 21:42:21 2012 |
rana | Frogs | Computer Scripts / Programs | dataviewer font error |
An error this evening on rossa: dataviewer not working due to some font errors:
controls@rossa:~ 0$ dataviewer
Connecting.... done
Warning: Not all children have same parent in XtManageChildren
Warning: Not all children have same parent in XtManageChildren
Warning: Not all children have same parent in XtManageChildren
Warning: Not all children have same parent in XtManageChildren
Warning: Not all children have same parent in XtManageChildren
Warning:
Name: FilterText
Class: XmTextField
Character '\52' not supported in font. Discarded.
Warning:
Name: FilterText
Class: XmTextField
Character '\56' not supported in font. Discarded.
Warning:
Name: FilterText
Class: XmTextField
Character '\170' not supported in font. Discarded.
Warning:
etc............. |
7950
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Mon Jan 28 21:36:44 2013 |
tall guy | Frogs | General | small people on notice |
If I catch anyone putting small booties into the large bootie bin, I will make said person eat small booties. |
7952
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Tue Jan 29 10:59:37 2013 |
lazy person | Frogs | General | better plan |
I propose we work around this problem with giant flip-flops. These are in the vein of the take-off-your-shoes-and-put-on-Crocs, without the taking off your shoes part. They're a little annoying on the sticky mats, but otherwise great. They are also super easy to put on and take off without hands, so there's no excuse for wearing them around the control room.
I propose we buy many pairs of the smalls in green (since we already have one green small...they are big on me, so should be just right for most people), and a few mediums in, say, blue, and a few larges in black, and then maybe a few extra larges in green for people with extraordinarily large feet (they only have 3 colors). Then we can keep a few pairs of each by each door to the lab, and have no more tracking dirty control room filth into the lab. |
7955
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Tue Jan 29 15:16:18 2013 |
Manasa | Frogs | General | trial run |
I would like to suggest a trial run on these....Ergomates and the cleanboot!


REPLY by JCD: Are these going to trap dirt and be impossible to clean though? The nice thing about Crocs and the giant flip flops is that they are solid and if they get dirty you can do a quick wipedown, and they're good as new. |
7967
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Wed Jan 30 16:24:25 2013 |
Manasa | Frogs | General | trial run |
Quote: |
REPLY by JCD: Are these going to trap dirt and be impossible to clean though? The nice thing about Crocs and the giant flip flops is that they are solid and if they get dirty you can do a quick wipedown, and they're good as new.
|
The Cleanboot is washable and reusable! |