patrick.thomas@LIGO.ORG - posted 11:02, Thursday 23 January 2014 (9487)
Jim B. restarting fw0 and nds0
We were measuring the green modulation depth in EX by looking at the transmitted power when locking the cavity on carrier or sidebands. To make the interpretation easier we first used the ifr to move the sidebands to exactly mid-fringe. With a length of 3994.472 m and a multiple of 650.5 we get a frequency of 24.410610 MHz. The ifr was set to +11 dBm for the measurement.
Here we report the measured RF levels. We used an Agilent N1914A with probe E4412A (S/N MY50270005). A zero check and calibration was performed before the measurement. An attenuator was added at the RF patch panel in the field rack between the balun and the cable driving the Pockels cell. As a comparison we list the attenuation values measured with the RF source at a frequency of 24.407079 MHz as well. We left the 12 dB attenuator installed and switched back to the RF source.
| Attenuator |
ifr +11dBm 24.410610 MHz |
RF source 24.407079 MHz |
|---|---|---|
| none | 13.69 dBm | 13.49 dBm |
| 6 dB | 7.74 dBm | 7.52 dBm |
| 12 dB | 1.72 dBm | 1.50 dBm |
For WP 4409
Work done, VEA transitioned back to laser SAFE.
The h1nds0 daqd will be shut down for up to 10 minutes to build RCG 2.8.2 versions of daqd to support longer frames. Longer frame collection should be implemented about 11:00 PST for h1fw0. Following about an hour of testing, and assuming testing is successful, longer frame writing will be implemented on h1fw1 about 12:00 PST.
Due to frame writer 0 crashing 35 minutes after starting while writing longer frames, we are delaying the change to framewriter 1 until 13:00 PST at the earliest.
HAM4 and HAM5 are different compared to HAM236, because of the ST0-L4Cs. Consequently, we need to use the proper blocks for the BIO cards.
The changes have been made (see pic attached), the models recompiled and restarted. Everything went fine.
Done
Done
@9:45
Thomas out of LVEA
Done
Restart DAQ to load new .ini file for h1isiham4.