  We search for variable sources, using the data of the surveys conducted on
the RATAN-600 radio telescope in 1980-1994 at 3.94 GHz. To test the radio
sources of the RCR (RATAN Cold Refined) catalog for variability, we estimated
the long-term variability indices V of the studied objects, their relative
variability amplitudes V_chi, and the chi-square probabilities p. Out of about
two hundred considered sources, 41 proved to have positive long-term
variability indices, suggesting that these sources may be variable. Fifteen
objects can be considered to be reliably variable according to the chi-square
criterion p > 0.98, three of these sources have chi-square probabilities p >
0.999. T he corresponding probabilities for six sources lie in the 0.95 < p <
0.98 interval, and those of the remaining 20 objects in the 0.73 < p < 0.95
interval. Twenty-four of 41 objects are variable or possibly variable in the
optical range, and five objects are known variable radio sources. We construct
the light curves and spectra for the sources with positive long-term
variability indices.
