Annu. Rev. Astron. Astrophys. 1992. 30: 653-703 Copyright © 1993 by Annual Reviews. All rights reserved

3.3.5 OBSERVATIONS AT MEDICINA AND TROMSÖ Mandolesi et al (1986) have carried out a series of observations at a wavelength of 3 centimeters at Medicina, Italy, and at Tromsö, at an altitude of 750 meters in the Norwegian arctic. Their most sensitive observations were those at Tromsö, where they used a 1.2 meter diameter antenna with two feeds such that the beam separation was 10° on the sky. The beamwidth was 2°.8 FWHM. They Dicke switched at 1000 Hz between one of the two feed horns and a reference horn. They measured the difference between the temperature in the two telescope beams. There were features of this data which looked like detected signals, but the same features were not seen in the Medicina data. They therefore ascribed the ``signal'' to instrumental and atmospheric effects and they deduced the upper limit on anisotropy given in Table 4.