Walker, Dallas (TE)
The San Diego Chargers have signed tight end Dallas Walker to a three-year contract.
Walker played for Western Michigan University from 2009-2011. He was out of football last season.
Brown, Cornelius (CB)
The Chargers agreed to terms on a one-year deal with Brown on Monday.
Brown spent time with the Chicago Bears and Indianapolis Colts. He played in 10 games with the Colts in 2010.
DePalma, Dan (WR)
The Chargers agreed to terms on a two-year deal with DePalma on Monday.
DePalma spent time on the Giants' practice squad in each of the last two seasons.
Butler, Deon (WR)
The Chargers agreed to terms with Butler on a one-year deal on Monday.
Butler played in 35 games during four seasons with the Seattle Seahawks, catching 57 passes for 611 yards (10.7 average) and four touchdowns.
Ohrnberger, Rich (G)
The San Diego Chargers signed Ohrnberger, the former Arizona Cardinals guard, to a one-year contract Thursday.
He was drafted by New England in the fourth round in 2009 out of Penn State. He played in five games his first two seasons with the Patriots, seeing limited time at right guard and on special teams. Ohrnberger spent the 2011 season on injured reserve due to a head injury and was released in February 2012. He signed with Arizona and played in 13 games last year, making two starts. He suffered a knee injury on Dec. 9 and was placed on injured reserve.