  The absolute temperature of the cosmic microwave background (CMB) has been
measured at a frequency of 1280 MHz. The observation was made with a modified
version of the L-band receiver used in the Giant Metre wavelength Radio
Telescope (GMRT): the feed horn was replaced by a corrugated plate and the
receiver was placed on the ground, directed at zenith, and shielded from ground
radiation by an aluminium screen with corrugated edges. Novel techniques have
been adopted for (1) reducing and cancelling unwanted contributions to the
system temperature of the receiver and (2) calibrating the contributions from
the feed assembly and receiver. The thermodynamic temperature of the CMB is
estimated to be 3.45 +/- 0.78 K.
