A valve tester suspension assembly for allowing one person to perform the tasks necessary to test underground valves includes an articulated arm attached to a mobile base such as a vehicle. The articulated arm may be biased such that the biasing assists in supporting the weight of a rotating assembly positioned at a distal end of the articulated arm. The articulated arm is pivoted to permit positioning of the rotating device in a substantially horizontal orientation at a desired position within a three dimensional space adjacent to the base to which the articulated arm is attached. A method of use is also described.