The time estimate includes time spent on the reference position (Position and Beam Switching) or the reference phase (Frequency Switching) excluding overheads. Add 15% on top of the calculated time for calibrations, pointing, antenna slewing and data handling. Projects requiring frequent frequency changes of the SIS-receiver should allow 15 minutes for each tuning. Frequency changes within each of the three HEMT receiver bands below 50 GHz are instantaneous; OSO staff members are required to change between bands. Such changes take about 30 minutes and are done daytime. Changes within and between the 3 and 4 mm bands are instantaneous.
      Note that the default temperature scale is in T^*_A units. To use the main beam brightness temperature scale (T_MB) enter the required sensitivity divided by the main beam efficiency.
      Simultaneous observations of two polarisation components are possible for all receiver bands except the range 26-36 GHz (LCP/RCP for the 7 mm, 1.0 cm and 1.3 cm bands, and H/V for the 3 and 4 mm bands), Note that the calculated time applies to a single polarisation, i.e., divide the calculated time by a factor of 2 if two polarisation channels can be co-averaged in the data analysis (e.g. if the sought signal is unpolarised).