Visible crew/equipment: When Charlie, who has smoke inhalation, is placed on the gurney in the treatment room, the actor's white tape mark is visible on the floor, where the nurse stands in a moment.
Continuity mistake: During the house fire, when Chet kicks the door twice he leaves dark marks on the door, but when he kicks the door a third time the marks on the door have vanished.
Camera Bug - S4-E10
Visible crew/equipment: At the accident scene with the truck carrying dynamite, when Roy is leaning over the driver's door, the outline of the mic transmitter is visible on the back, right side of his shirt. Then, when they're carrying the driver to the top, Johnny's becomes visible at his left side.
Camera Bug - S4-E10
Visible crew/equipment: When Johnny is driving Roy nuts by taking closeup pictures of him checking the squad's engine, the outline of the lavalier mic wire is visible on Johnny's back.
Camera Bug - S4-E10
Visible crew/equipment: At the school fire, when Johnny is administering the O2 to the teenager with smoke inhalation, the bulging outlines of the mic transmitter and wire are visible on the back, left side of Johnny's shirt.
Visible crew/equipment: When all the guys are talking to Mr. Gibson, who is stuck in the trench he fell into, the outlines of the lav mic transmitters are visible on the backs of Roy's and Johnny's shirts.
Continuity mistake: When Dr. Morton leaves the room of the patient who attempted suicide to get Jack, he takes the pill bottle from Dr. Early, carries the medical chart holder, and is wearing a stethoscope around his neck, but in the hallway when he gets Jack the pill bottle and chart holder are gone, and the stethoscope is in his pocket. Then, when they walk back into the room, Morton's holding the bottle and chart holder, and the stethoscope is back around his neck.
It's How You Play the Game - S4-E19
Continuity mistake: When Johnny is in the ambulance with the car salesman that was bitten by the tiger, Johnny opens the man's shirt, but does not remove his western tie scarf. However, in the man's closeup the tie is open with the scarf slide removed, and then it's back to being tied with the slide.
It's How You Play the Game - S4-E19
Visible crew/equipment: When Roy and Johnny are on scene at the car accident, the bulging outlines of their mic transmitters and wires are visible on the left sides (above the belts) of their shirts.
Continuity mistake: When Chet and Marco are hosing the gas meter fire, they are both wearing gloves while handling the hoses. However, after Roy helps Chet up from his stumble, there is a closeup of the hoses and it's a bare hand handling the hose.
Peace Pipe - S2-E5
Continuity mistake: After Roy and Johnny find the source of the fuel oil getting into the water supply, when they pull up behind the van, there are three barricades with flashers. The flasher on the sidewalk barricade flips from one side to the opposite side between shots.
Peace Pipe - S2-E5
Continuity mistake: When Johnny and Roy arrive at the apartment with the woman who can't breathe because of her new girdle, she hangs up the phone receiver with the cord across the base. In following shots the receiver is placed properly, and then the other way again.
Continuity mistake: When Roy and Johnny are driving to the parade in the fixed up old engine, they repeatedly switch between the road's right lane and left lane, depending on the camera angle.
Deliberate mistake: During the rescue of the car at the top of the draw bridge, The Boat approaches and radios in to say that they have a diver standing by. Then after Johnny shouts, "Are you all right?" the rescue boat is shown again, but this time it's a flipped shot - note that everything is reversed from the prior shot.
Continuity mistake: When Squad 51 and the ambulance arrive at Rampart with the father and unconscious diabetic son, the type of ambulance that backs up to the ER entrance is a station wagon, but in the interior shot from Rampart the ambulance type is a truck.
Visible crew/equipment: When Johnny and Roy are at the home of the pregnant woman who was shot, the bulging outline of the mic transmitter is visible on the back, left side of Johnny's shirt.
Daisy's Pick Blind Date - S4-E7
Visible crew/equipment: When the unconscious little boy is loaded into the ambulance, we see the actors' chalk x marks on the ground, where Roy, the boy's father, and mother are all standing.
Visible crew/equipment: After Cora is rescued from the cactus patch, when Harry annoys her and tells her to keep a stiff upper lip while she's lying on the gurney, the reflections of crew members and two reflector screens are visible on Harry's red bike helmet.
Visible crew/equipment: When Johnny and Roy help Cora crawl along the ladder from the cactus patch located in a secluded area, just as Johnny tells her to take it nice and slow, the camera moves a bit too far to the left and then shifts back to the right, but not before we are able to see a crew member, equipment and a large patio-style umbrella.
Visible crew/equipment: When Roy treks across the ladder to get to the woman in the cactus patch, the outlines of the lav mic transmitter and wire are visible at the back, right side of Roy's shirt. Then, when Johnny's on the Biophone with Rampart, the outline of the mic transmitter is visible at the back, left side of Johnny's shirt.
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.