MA-1 Radar Rack Solid State Receiver. Courtesy of Marvin Donnelly who writes: Anyone remember the one adjustment we MA-1 types had to do on this receiver? Hughes engineers DID NOT like my suggestion to help out with it. The "Short Radar Range" check was set to produce a V.I. target at about 200 yards from the nose of the aircraft. This was to ensure the VI interceot could get the aircraft to within the 500 foot down and aft of a target. The potentiometer was in the receiver and would require removing all 20 or so screws from the receiver to accomplish it. The Hughes engineers did not like my suggestion of putting in a hole in the top plate - in order to make the adjustment - without removing the plate. When asked about how I would stop anything from getting in and how to keep it pressurized I told them to put in a rubber stopper! Like one of those thermos jug stoppers with the lever on it! The suggestion was NOT accomplished!