Continuity mistake: When Roy and Johnny are in the apartment, just as Mr. Jefferson mentions that Shorty brought in hot tractors, it cuts to a closeup of Roy who is not wearing a stethoscope, but in the next shot the stethoscope is suddenly around Roy's neck.
Continuity mistake: When the woman from the car accident is in the ER, Brackett tells Morton to intubate her and Morton grabs the laryngoscope and slides her body down on the gurney to a proper position, but in the next shot from another angle Brackett orders the intubation again and the same things are repeated.
Continuity mistake: While the woman from the car accident is in the ER, when Brackett tells Morton to intubate her Morton has a penlight (to check pupillary response) in the pocket of his scrubs, but in the following shots that penlight keeps vanishing from his pocket and reappearing.
Visible crew/equipment: After Chet gives Johnny the idea about the TV show, when Chet stands up to leave the kitchen the top of the set is visible at the right corner.
Visible crew/equipment: After Dr. Early tells Mr. Jefferson that he knows who he is, it cuts to Johnny at the table with the typewriter, and the shiny chrome surface of the coffee pot reflects multiple set lights.
Continuity mistake: At the scene of the vehicle accident, once Vince wraps the gauze around the head of the driver of the pickup truck, the same bystanders are standing in two places at once - on the sidewalk beside Engine 51 and across the street beside Squad 51.
Continuity mistake: When Station 51 is dispatched to the 'man trapped between two buildings', Roy is not wearing a watch when he and John head out on the lines between the buildings and also when they get back on the roof, but during the actual rescue while on the lines, both stunt guys are wearing watches on their wrists.
Continuity mistake: When Station 51 is dispatched to 'man down' at Hotel Potter, the address is given as 11876 Fishburn, between MacArthur and West 7th, but when the squad and engine are in front of the building, the corner street signs read Trenton and Parkview.
Visible crew/equipment: When Johnny and Roy are on the soap opera set treating the 'doctor', the outlines of the lav mic transmitters are visible on the front, left sides of Johnny's and Roy's shirts, above their belts, and the outline of Jody's mic transmitter is visible on the back of her brown sweater.
Revealing mistake: At the movie studio, when the actor who plays Dr. Ned is loaded onto the ambulance stretcher, their set's 'fake' window area is the same as Rampart's 'real' hallway later in the episode. We can see this when Brackett, Early and Dix walk down the hallway to kick Dr. Ned's film crew out of his room. Pretty funny to see the same chairs, wall, window with painted exterior backdrop and color stripes on the floor. This area of Rampart can also be seen in the previous episode 'Family Ties', when the clock radio shorts out causing a fire in the patient's room.
Visible crew/equipment: When Roy and Johnny are stuck in the elevator with the cardiac patient, the outline of the lav mic transmitter is visible on the front, left side of Roy's shirt, above his belt.
Other mistake: When Johnny, Roy, and the cardiac patient are stuck in the stalled elevator with smoke in the shaft, Captain Stanley notifies dispatch that he wants a full first-alarm assignment, and we then see Engine 8 pulling out of their bay and heading to their run. The problem here is that this shot of Engine 8 is from the episode "Equipment" in season 5, when Johnny was doing overtime with Station 8, and we can actually see Johnny sitting on Engine 8 as it drives by.
Visible crew/equipment: When Roy walks into the ER with the actor who plays Dr. Ned, the nurse rushes over to Roy, and when she asks him about the actor, we can see the bulge of the lavalier mic transmitter at the back of her uniform.
Continuity mistake: When all the guys enter the apartment with the doctor lying on the couch, John's carrying the Biophone with his right hand and starts to place it down, but then it cuts to another angle and John's holding the Biophone in his left hand as he places it down.
Visible crew/equipment: After we see Marco and Captain Stanley heading up to the roof, it cuts to a shot in the elevator when Roy says "The firemen are working as hard and as fast as they can, to get us down from here," and the crew's moving shadow can be seen on the left, where the camera is located at the elevator doorway.
Continuity mistake: After Early tells Dr. Ned that he thinks he has mononucleosis, when Early leaves the room, the nurse that's in the room with Dixie walks away from the patient to the other side of the room, but in Dr. Ned's closeups that nurse is still standing behind him while he talks to Dixie.
Revealing mistake: After Johnny's line gets snarled while testing Wally's equipment at the studio, when Roy lowers himself on his own line wearing his lifebelt, we can see the added carabiners that are attached to the lifebelt which go down into Roy's pants, and are presumably attached to the extra support the actor is wearing under his pants.
Visible crew/equipment: At the refinery fire, after Roy gets into the ambulance with the patient Johnny shuts the back doors, and when the ambulance backs up the reflection of a crew member with paperwork (script?) is visible in the left ambulance window.
Revealing mistake: At the studio, in the overhead shot just as the squad is about to reach the building where Johnny will be testing Wally's equipment, the 'Black Tower', which houses Universal's executive offices, is visible in the background, and then in the roof shots when each of the guys repels down individually, the Sheraton-Universal is visible in the background.
Visible crew/equipment: When Roy and Johnny are with Johnny's friend, the stunt coordinator, trying out the new gear, the outlines of their mic transmitters are visible on the left sides of Johnny's and Roy's shirts, above the belts.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.