Anomalies in ohmic losses in HTSC ceramics are considered in the low- and radio-frequency ranges. It is found experimentally that the width of theN–Stransition in the ceramics(YBa2Cu3O7+1&percent; 57Fe),SmBa2Cu3O7,andYBa2Cu3−xScxO7in a weak magnetic field (up to 50 Oe) becomes smaller in the frequency interval betweenfcandfFat which the resistance does not depend on temperature. It is shown that, for some types of HTSC and for different samples of the same type, the frequencyfcdoes not correlate with the superconducting transition temperatureTc.©1998 American Institute of Physics.