High-sensitivity, high-spectral-resolution solar observations in the m
illimeter wavelength are scanty. A sensitive radiometer with 1 GHz res
olution, operating between 18 and 23 GHz in conjunction with a 13.7 m
diameter antenna has been in regular operation since the end of 1987.
At present, each frequency is sampled for 100 ms, soon to be improved
to 50 ms. Details of this instrumentation, including the processes of
calibration, data acquisition, and reduction are described here. Also,
preliminary observations of an active region and of the burst compone
nts are briefly described.