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.