All antennas are currently equipped with receivers that can simultaneously observe in two frequency bands. The guaranteed frequency range is 82 to 116GHz for the 3mm band, and 205 to 245GHz for the 1.3mm band. Proposals requesting frequencies outside the guaranteed frequency bands will be tagged ``special'' and scheduled (if recommended by the PC) on a best effort basis only.
Below 105GHz, the current receivers offer best performance in LSB tuning with high rejection (20dB): expected system temperatures are 100 to 150K for the winter time. Above 105GHz, best performance is obtained with USB tuning, low rejection (4 to 6dB): expected system temperatures are 250K at 115GHz.
The current 1.3mm receivers have DSB tuning with typical T
below 50K. Expected SSB system temperatures are 350 to 450K.
The guaranteed tuning range is 205-245GHz, but it is possible to
reach some lower and higher frequencies. Higher frequencies are not
feasible on all antennas because of limitations in the triplers. For
details about observing at frequencies slightly below or above the
guaranteed tuning range of the 3mm and 1.3mm receivers, please get
in touch with the Interferometer Science Operations Group
(sog@iram.fr).