A high-resolution microwave spectrometer has been developed by converting the Owens Valley solar interferometer to frequency-agile operation. The system uses 27 m antennas equipped with phase-locked receivers which can change their observing frequency in 25 or 50 ms. Microwave spectra between 1 and 18 GHz are obtained in a few seconds by successive observations at up to 86 discrete frequencies. At each frequency the data are equivalent to the total power from each antenna and the interferometric amplitude and phase. All data are fully calibrated with respect to cosmic sources.The instrument was motivated by the need for better microwave spectral resolution for the study of plasma parameters, non-thermal electrons and coronal magnetic field strengths in solar flares and active regions. Early observations with the system are illustrated by a sequence of flare spectra featuring cases with exceptionally narrow continuum bandwidths.

The two 90-foot steerable paraboloids of the Orrens Valley Radio Observatory were used as a tw-o-element interferoneter at 960 Mc/s with various separations along a north-south baseline to measure accurately the declinations of a number of radio sources, most of which were of small diameter. The measured values of declination are tabulated for 110 sources with right ascensions between 0 hours and 14 hours 10 minutes. The standard errors of the measured values range from :t 2. 6 seconds of arc to ± 46 seconds of arc with an average of :.t 13 seconds of arc. A discussion of the sources of error is included.

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