Temporary page for filling in details on the NOEMA April 2019 setup.
Mark6 setup
Installed vdifstream git repository utilities:
vdiftimeUDP : UTC vs realtime VDIF timestamp monitoring
vdifsnapshotUDP : burst mode capture to memory then disk
vdifcontinuitycheck.py : report VDIF frame continuity (threads, lost frames, reordered frames, thread misalignment)
fuseMk6 : mount the disk module as readable proper gatheredVDIF files
Installed Mark6 disk spin-down prevention CRON job as described in https://eht-wiki.haystack.mit.edu/Event_Horizon_Telescope_Home/Observing/0_General/Recorders/Disk_Module_Spin-Down_Prevention and a copy of the script (fixed for Mark6 bash version) is disk-toucher.sh
/etc/dhcp/dhclient.conf
append domain-name-servers 193.48.252.22, 192.168.200.50;
Practical details
Mounting Mark6 modules for reading off files
oper@recorder1:~> sudo mkdir -p /mnt/fuse/12 oper@recorder1:~> sudo mkdir -p /mnt/fuse/34 oper@recorder1:~> sudo chown oper:oper /mnt/fuse/12 oper@recorder1:~> sudo chown oper:oper /mnt/fuse/34
oper@recorder1:~> fuseMk6 -r "/mnt/disks/[1-2]/[0-7]/data/" /mnt/fuse/12 oper@recorder1:~> fuseMk6 -r "/mnt/disks/[3-4]/[0-7]/data/" /mnt/fuse/34
oper@recorder1:~> fusermount -u /mnt/fuse/12 oper@recorder1:~> fusermount -u /mnt/fuse/34
Note, a lot of utilities (e.g., m5spec, m5tone) could not be installed on the Mark6 because the ancient Debian Squeeze archive key is expired and keys cannot be refreshed by apt-key, so cannot install new packages such as the FFT library fftw (maybe there is a way to get apt-get working again?).
Access on EHT-CC server to Mark6 FUSE-mounted modules
[root@cc-noema ~]# pacman -S sshfs [oper@cc-noema zerobaseline]$ mkdir -p zerobaseline/recorder1_fuse_12 [oper@cc-noema zerobaseline]$ mkdir -p zerobaseline/recorder1_fuse_34
[oper@cc-noema zerobaseline]$ sshfs recorder1:/mnt/fuse/12/ /home/oper/zerobaseline/recorder1_fuse_12/ [oper@cc-noema zerobaseline]$ sshfs recorder1:/mnt/fuse/34/ /home/oper/zerobaseline/recorder1_fuse_34/ [oper@cc-noema zerobaseline]$ m5spec recorder1_fuse_34/test_Na_tone512M.vdif VDIF_8192-8192-1-2 65536 2000 r2dbe_if1_65kpt.spec [oper@cc-noema zerobaseline]$ gnuplot > plot "r2dbe_if1_65kpt.spec" using 1:2 with lines
Zero baseline test
Scripts are under https://bitbucket.org/jwagner313/apex-tools in Correlation/DiFX_zerobaseline_generator/r2dbe_r2dbe/
They use the program 'vsum' from DiFX library vdifio, DiFX vex2difx, and DiFX mpifxcorr. Additionally HOPS fourfit is required for the fringe fitting and fringe plot.
Coherence test tone phase extraction
Tone phase extraction script m5tone.py is part of DiFX library mark5access Python extensions and its examples.
Prerequisite libraries, installation:
[root@cc-noema ~]# pacman -S python-numpy
[oper@cc-noema python]$ cd /home/oper/difx/svn/libraries/mark5access/python [oper@cc-noema python]$ python setup.py build [oper@cc-noema python]$ python setup.py install --prefix /home/oper/difx --install-lib=/home/oper/difx/lib/python/ [oper@cc-noema python]$ cp examples/*.py $DIFXROOT/bin/
Then with a test recording make 10 millisec integrations with tone expected at 512 MHz and using 8192k-point FFT:
[oper@cc-noema zerobaseline]$ m5tone.py recorder1_fuse_34/test_Na_tone512M.vdif VDIF_8192-8192-1-2 \
tone512m.m5s 1 0.010 512e6 $((8192*1024))
Tone at 512000.000 kHz in the 2048.000 MHz wide band lands in 0.488 kHz-wide bin 1048576.
Integrating for 10.24 milliseconds with 5 spectra per integration.
58576.907001684 mjd : 0.005120 sec : 3.327136e-02 /_ -120.35 deg : r=1.000
58576.907001802 mjd : 0.015360 sec : 3.352154e-02 /_ -120.04 deg : r=1.000
58576.907001921 mjd : 0.025600 sec : 3.325227e-02 /_ -120.06 deg : r=1.000
58576.907002039 mjd : 0.035840 sec : 3.340412e-02 /_ -119.87 deg : r=1.000
58576.907002158 mjd : 0.046080 sec : 3.321879e-02 /_ -120.00 deg : r=1.000
...
[oper@cc-noema zerobaseline]$ gnuplot
set yrange [-185:185] ; set y2range [0:1.05] ; set xlabel 'Time (s)'
set ylabel 'Tone phase (deg)' ; set y2label 'Coherence'
plot "tone512m.m5s" using 2:4 title 'tone phase' axes x1y1, \
"tone512m.m5s" using 2:5 title 'tone coherence' axes x2y2 
