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:

> setupCCCL  for the C-band receiver (narrow bandwidth)
> setupCCC   for the C-band receiver (wide bandwidth)
> setupCHCL  for the C-high-band receiver (narrow bandwidth)
> setupCHC   for the C-high-band receiver (wide bandwidth)
> setupXXP   for the X-band receiver
> setupKKC   for the K-band receiver

Note

Spaces within the command line content are not allowed!

The above 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

LO freq

Frontend IF band

Backend IF band

Observed bandwidth

Observed band

code

(MHz)

(MHz)

(MHz)

(MHz)

(MHz)

CCCL

4600

100-250

50-250

150

4700-4850

CCC

4600

100-900

50-780

680

4700-5380

CHCL

4600

100-250

50-250

150

6500-6650

CHC

4600

100-900

50-780

680

6500-7180

XXP

8080

100-900

50-780

680

8180-8860

KKC

21964

100-2100

50-2400

2000

22064-24064

Notice that, depending on the devices in use, the sky frequency at the observed band starting point is given by the LO frequency plus an offset. For the present combinations of the frontends with the total power backend, which the above table refers to, this offset is 100 MHz. In general, 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).

Logfile and project code

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.

It is possible, and advisable, to insert the project code/name (a string assigned to the project by the TAC) using the command:

> project=[projectcode]   (e.g. project=maintenance)

This will make the user save time in later stages, as it will not be necessary to specify the project name in schedule-launching commands. The project code/name must correspond to an existing user, already known to the system. This means that, if its spelling does not match with the recorded name, an error rises.