Initial setup

Antenna overall setup

When opening a DISCOS observing session, it is necessary to perform a setup which includes the antenna unstow, the mount configuration in tracking mode, the minor servo setup. This is done by means of a unique command, which is specific for the wanted receiver, to be written in the operatorInput. The currently available choices are:

> setupSXP     for the SX-band receiver
> setupCCC     for the C-band receiver
> setupMMC     for the M-band receiver
> setupKKC     for the K-band receiver
> setupQQC     for the Q-band receiver

WARNING:

  • It is necessary to manually select the observing focus using the hardware IF switch located in the control room. The figure below illustrates this rack.
Hardware switch in charge of selecting the IF lines to be used, i.e. selecting the observing focus.

The general setup command sets the antenna mount, the minor servos, the selected receiver and the default backend (TotalPower) according to default parameters. The antenna mode is set to ProgramTrack (allowing tracking and the execution of schedules), while the Local Oscillator frequency and the bandwidth are set as illustrated in the following table.

Receiver code LO freq (MHz) Frontend RF band (MHz) Backend IF band (MHz) Observed bandwidth (MHz) Observed band (MHz)
SXP 2020 2200-2360 50-730 160 2200-2360
SXP 8080 8180-8580 50-730 400 8180-8580
CCC 4600 4620-5020 50-730 400 4650-5020
MMC (1) 6956 5100-7250 50-730 500 6356-6856
KKC 21869 21500-23000 50-730 400 21969-22369
QQC 42850 39000-43500 50-730 400 42950-43350

Notice that the true observed band depends on the intersection between the frontend IF band and the chosen backend filter. The actual observed bandwidth and the band starting frequency are recorded in the output files (see Appendix C - Output files).

(1) For this setup, the FITS file will NOT report the actual values relative to frequency and bandwidth, as the present DISCOS release does not take into account the different conversion taking place for this receiver.

Logfile

The default logfile is named station.log. If the user wants to change it:

> log=[logfilename]  (without extension)

Logfiles are stored in a dedicated folder (see Retrieving the data). When schedules are run, a new logfile is automatically started, and it is named after the schedule: [schedulename].log.