Every Monday night at O’Conners Vault in Multnomah Village (7850 SW Capitol Hwy), Dave Fleschner and his trio host a jam session.  The trio (with Charlie Doggett on drums and Dan Gildea on guitar) open up the evening with an hour of their music starting at 8 PM, and at 9, musicians are called up to join in.  The show is free for musicians - other audience members pay a $5 cover.