Original: W \* A \* L \* T \* E \* R was the pilot for a television series that was not picked up. It would have featured Gary Burghoff reprising the role of Walter O'Reilly, who is no longer referred to as "Radar."
Simplified: The second spin-off was W \* A \* L \* T \* E \* R \*, which was about Walter "Radar" O'Reilly (Gary Burghoff).