May 23rd, 1976: First ever EME QSO in OK country on 70 cm with WA6LET. 7.5m dish was shortly borrowed by the Astronomical Institute of Czechoslovakia.
Since 2002 up today:4.5m solid dish (F/D≈0.42) on Az-El mount
1980 to 2002 (22 years):4m solid dish (F/D≈0.35) extended to 5.5m(F/D≈0.25) on tripod polar mount