When Harm and Dunwoody are playing basketball, the US flag is hanging incorrectly behind the basket. The union (blue field of stars) should be on the left, not the right. For a military-based show, this should have been caught.
When Harm is talking to Dunwoody's mother, they are supposed to be in Washington, D.C., but there is a Metrolink train which operates in Los Angeles and Orange Counties in California passing in the background.