1.3 mm Receivers

• 230G1: Operating band: 203.4 -- 246 GHz. The SSB receiver temperature is 100 -- 180 K in the standard reference plane.

• 230G2: The SSB receiver temperature over the nominal tuning range (210--250 GHz) is 100--130 K in the standard reference plane. The upper side band can be rejected by typically dB over this range. This receiver can be tuned to 267 GHz, although with a higher noise temperature ( K). See the March 1994 Newsletter for more details.

Beware of possible interference of the 230G2 LO into the 3 mm receivers. The 230G2 receiver cannot be operated with the 2 mm receiver, since both receivers use the same control box and polarization. Switching from one receiver to the other is not straightforward. Please specify in the proposal form whether you choose to use the 2 mm receiver 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.