Gary Richard Burghoff (born May 24, 1943) is an American actor, known for playing the character Corporal Walter Eugene "Radar" O'Reilly in the MASH series and Charlie Brown in the 1967 Off-Broadway musical You're a Good Man, Charlie Brown. Description above from the Wikipedia article Gary Burghoff, licensed under CC-BY-SA, full list of contributors on Wikipedia.
M*A*S*H
1970
Casino
1980
Altman on His Own Terms
2000
Memories of M*A*S*H
1991
The Man in the Santa Claus Suit
1979
Twigs
1975
M*A*S*H: 30th Anniversary Reunion
2002
M*A*S*H: The Comedy That Changed Television
2024
B.S. I Love You
1971
Small Kill
1992
Behind the Waterfall
1995
Daniel's Lot
2010
W*A*L*T*E*R
1984