We have produced an image of the microwave sky with 30 ^ { \prime } resolution in a 2 ^ { \circ } field using the Cosmic Anisotropy Telescope ( CAT ) .
Analysis of data taken at three frequencies near 15 GHz indicates that most of the signal is due to the CMB , with an equivalent broad-band power of \Delta T / T = 1.9 ^ { +0.5 } _ { -0.5 } \times 10 ^ { -5 } at angular scales corresponding to multipoles l = 320 –500 , and \Delta T / T = 1.8 ^ { +0.7 } _ { -0.5 } \times 10 ^ { -5 } at l = 500 –680 .
We are now building a more advanced instrument , the Very Small Array ( VSA ) , which will cover the range l = 130 –1800 with a sensitivity per resolution element of \Delta T / T \sim 10 ^ { -6 } .