Recent improvements in hardware, software and mixers have made possible frequency switching with satisfactory baselines. Several limitations exist e.g. in terms of frequency throw (max. 45 km/s), backends, phase times etc. For details see . Frequency switching is now open for public use. The receivers 3 mm, 230G1 and 2mm can be frequency switched simultaneously. However, baselines may be better when only using the 3 mm and/or the 230G1 receiver(s) due to the different optical setup.
An instantaneous IF bandwidth of 1 GHz will be available for the 230G2 receiver on an experimental basis. The two 1 MHz filterbanks (512 MHz each) can be combined to provide 1 GHz bandwidth. The use of the 1 GHz wide filterbank excludes the simultaneous use of any other backend with the 230G2 receiver (the other receivers are not affected). The setup for 1 GHz bandwidth is being prepared, and progress will be announced in the Newsletter.
A second 3 mm receiver (3mm2) is being built presently and should be operational this fall. It will be usable simultaneously with the present 3 mm receiver (3mm1) and, with some extra losses, with 230G1 and 230G2. Its performance is not yet known, but should be similar to that of 3mm1. Since we have so far no experience with 4-receiver operation, this new receiver should normally not be considered in the telescope time calculations.
Most proposals submitted for the 30 m telescope underestimate the observing time needed to carry out the programme, even under excellent weather conditions. We ask you to pay special attention to this matter as time underestimation is now a major criterion for proposal rejection (several programmes were rejected in April by the Program Committee on that ground). A technical report has been issued to help you to this matter . You may also ask for IRAM's assistance (but well before the deadline!).
The 19-channel MPIfR bolometer, which was installed in March 1995 on the 30-m telescope, will again be available this winter for 4 weeks, presumably during February/March. This bolometer showed excellent performances during last year's observing run.
Finally, to help us keeping up a computerized source list, we ask you to fill in your `list of objects' as explained below.