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 are instantaneous; OSO staff members are required
to change between bands. Such changes take about 30 minutes and are
done daytime.
     
Note that the default temperature scale is in
T*A
units. To use the main beam brightness temperature scale
(TMB) 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 HEMT bands,
H/V for the 3mm band). 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).
An approximate receiver temperature of 60 K has temporarily been adopted for the new SIS receiver (84-116 GHz) in the calculator while commissioning activity is still under way.