Ionospheric absorption of radio waves during the annular solar eclipse of April 29, 1976.

The effect of the cited annular eclipse on the time variation of ionospheric absorption at frequencies of 1.8, 2.2, and 2.6 MHz over Ashkhabad, USSR, is examined. A slight decrease in absorption with increasing frequency is found along with a moderate increase in E-layer reflection height at all three frequencies. It is shown that at the maximum phase of the eclipse, ionospheric absorption attained a minimum value of 4 dB, which corresponds to nighttime conditions.