R2DBE system setup

    Version as of 07:51, 18 Dec 2024

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    Pre-Checks

    • Check that the 1pps is connected to all R2DBE units (frontside)
    • Check that the IFs are connected to the Block Down Converter (BDC) with RCP and LCP as labeled on the backside
    • Check that the 10MHz signal is connected to the clock synthesizer unit
    • Check that the 10MHz signal is connected to the BDC unit
    • Check that the both IF input pins of all R2DBE units (frontside) are connected by cable
    • Check that all R2DBE units are connected by ethernet (PPC net port)  to the network hub box (backside)
    • Check that the noise generator unit is connected by ethernet to the network hub box (backside)
    • Check that all mark6 units are connected by ethernet cable to the the network hub box (backside)
    • In case you want to inspect the R2DBEs autocorrelation spectra make sure you insert a tone into the noise generator unit (backside)

    Startup sequence

    1. power on the mark6 units
    2. power on the clock synthesizer units
    3. power on the BDCs
    4. power on the R2DBEs
    5. power on the noise generator (optional)

    Verify unit startup

    • log into recorder1 as user oper. If logging-in does not work the mark6 machine is probably stuck in booting. Connect a display and keyboard and check.
    ssh recorder1 -l oper -X
    
    • do the same for the other recorders
    • log into the control computer  as user oper. Verify that all the R2DBEs units have booted up by trying an ssh connection:
    ssh r2dbe1 -l root
    ssh r2dbe2 -l root
    ...
    exit from r2dbe1, r2dbe2, ...
    

    if one of the units does not boot consult the Troubleshooting section below.

    Configuring the R2DBEs

    • log-into the control computer as user oper:
    ssh vlbicc -l oper
    
    • stop the monitoring daemons
    r2daemons_stop
    
    • initialize all the R2DBE units by running:
    start_backend.py /home/oper/pv-backends.conf
    

    alternatively the backends can be initialized individually:

    start_backend.py /home/oper/r2dbe1.conf
    start_backend.py /home/oper/r2dbe2.conf
    ...
    start_backend.py /home/oper/r2dbe4.conf
    
    • start the monitoring daemons
    r2daemons_start
    

    Verify R2DBEs

    • log-into the control computer as user oper:
    ssh vlbicc -l oper
    
    • adjust the 2bit sampling threshold:
    alc.py r2dbe1
    

    repeat for r2dbe2, r2dbe3 and r2dbe4

    • start the monitoring tool:
    r2dbe_monitor.py r2dbe1
    

    Check the power levels. if too low or two high adjust the attenuator settings of the BDCs accordingly

    Check the 2-bit sampling statistics. If not correct rerun alc.py

    Troubleshooting

    R2DBE unit does not boot

    • Connect a USB cable from the R2DBE (backside  "FTDI USB" port) to one of the USB ports on pv-mark6-1
    • log-into pv-mark6-1 as root
    • run:
    screen /dev/ttyUSB2 115200
    
    • hit the "enter" key. If the log-in prompt of the r2dbe unit appears go on to section XXXX
    • reset the R2DBE unit. In the screen window you should see the R2DBE booting. Inspect any messages that could indicate an error
    • press ctrl-a to leave the screen session

    R2DBE unit has booted but is not reachable from the mark6 machines

    • very likely the R2DBE has been assigned the wrong IP-adress by the dnsmasq service running on the control computer.
    • log-into the control computer  as user root
    • run
    /etc/init.d/dnsmasq restart
    
    • reset the R2DBE unit