Operating band: 203.4 -- 260 GHz. Between 203 and 245 GHz, the SSB receiver temperature is 100 -- 180, between 245 and 260 GHz, it is 180 -- 300 K.
This receiver, which was out of order for the last two months, will be repaired in February-March. It is planned to install a new mixer. We expect performances comparable to those of 230 G1 in the 210-255 GHz band.
The two 1.3 mm receivers and the 3 mm SIS RX can be used simultaneously. Beware, however, of possible interference of 230G2's LO into the 3 mm RX. The 230G2 RX cannot be operated with the 2 mm receiver, since both receivers use the same control box. Switching from one RX to the other is not straightforward and will not be made upon request in real time. Please specify in the proposal form whether you choose to use the 2 mm RX or 230G2.
At 1.3 mm (and a fortiori at shorter wavelengths) a large fraction of the receiver radiation pattern is distributed in an error beam (which can be approximated by two Gaussians of HPW and --- see A&A 274, p.144-146 for more details). Astronomers should take into account this error beam when converting antenna temperatures into brightness temperatures.