.. _E_Frontend-operations:

*******************
Frontend operations
*******************


General rules
=============

To change the frontend Local Oscillator frequency, use the following command:: 

    > setLO=[freq1];[freq2];…;[freqN]

Notice the semicolon. Ideally, different values could be assigned to different 
IFs, thus tuning each section to a different sub-band. For the present 
hardware, though, this is not possible, so a single value must be specified: 

	e.g. ``> setLO=22000`` 

Remember that the actually observed band begins at a frequency which is 
usually different from the LO one (see Initial setup)

The temperature of the calibration mark in use is recorded in the logfile 
whenever a Tsys is measured. It is also stored in the FITS output files. 
The calibration mark can be manually switched on and off respectively with:: 

    > calOn 
    > calOff


If the user wants to perform the setup for the frontend only (without 
affecting the mount, the minor servo or the backend), the command is:: 

    > receiversSetup=[code]   (CCC, CCL, CHC, CHCL, XXP, KKC)