Visible crew/equipment: After Roy and Johnny pick up supplies at the nurses' station, they walk down the hallway and stop midway to talk about Johnny's insomnia. After speaking a few moments, Johnny and Roy head for the exit, so the camera follows them without cutting away, and when a father and son enter the hospital the camera turns, without cutting away, and follows them up the hallway. Just before the father and son reach the nurses' station, the actors' two black tape mark are visible on the floor behind them, precisely where Roy and Johnny had been speaking.
Visible crew/equipment: When Roy and Johnny are at the nurses' station talking about Johnny's insomnia, after Johnny signs for the supplies, as they walk away the actor's black tape mark is visible on the floor, where Roy had just been standing.
Visible crew/equipment: When the man from The Boat explosion is loaded into the ambulance, the outlines of the mic transmitter and wire are visible on the back of Roy's shirt, as he climbs in after the gurney.
Heavyweight - S3-E5
Visible crew/equipment: When Roy and Johnny are with the guy who got stuck in the tree while hang gliding, the outlines of the mic transmitters and wires are visible on the back of the victim's sweater and also the back of Johnny's shirt as he saws the branch, and then carries the victim to the Stokes.
Visible crew/equipment: When Jason prevents Johnny from falling at the rock quarry, the outline of the mic transmitter is visible on the back of Jason's shirt (left side) in the overhead shot, as he hoists Johnny onto the platform, Then just after Johnny says that they should get out of there, in the shot of Roy bending over the trapped man, the outline of the mic transmitter is visible on the back of Roy's shirt.
Visible crew/equipment: During the boating accident rescue, the outlines of the mic transmitters and wires are visible on the backs of both Johnny's and Roy's shirts, on their right sides.
Inventions - S3-E22
Visible crew/equipment: On site at the chemical leak, when Captain Stanley talks into his handie-talkie and says "Engine 36, we're not doing any good with this, let's try light water," in the next shot, while the camera pans to the right, we can see a cameraman (filming Deluge 105's closeups that we see during this scene) holding his handheld, standing in front of an engine and facing Deluge 105, just before the camera focuses on the guys with the hoses.
Visible crew/equipment: At the refinery fire, after the stokes is loaded onto the snorkel and then John and Roy climb in, two shots after Captain Stanley's closeup, in the shot tilting up at the descending snorkel basket, a crew member who is crouching down can be seen on the tower behind it (presumably it's the second cameraman shooting all the footage from that angle).
Visible crew/equipment: When Squad 51 is dispatched to the "possible heart attack," just as the squad rolls up on scene, we can see its real license plate with number 70324H, instead of the prop plate number E999007.
Visible crew/equipment: When Roy and Johnny are with Dixie, they see the new unit and scanner at the base station, and when Roy walks over to it, the actor's white tape mark is visible on the floor where he stands.
Visible crew/equipment: When Johnny chases Harriet down the street, behind Johnny we see Roy backing up the squad to follow them, with nobody around, then when it cuts to the view from within the squad, the reflection of crew is visible in the driver's side mirror.
Visible crew/equipment: When Roy gets the little girl, Angie, out of the wrecked airplane and then places her in the Stokes basket, the outlines of the mic transmitter and wire are visible on the back of his shirt.
The Promise - S3-E11
Visible crew/equipment: After Squad 51 is dispatched to 'woman down', just as the squad rolls up in front of the apartment building we can see a bit of the camera's production equipment at the bottom left corner of the screen, which is then pulled quickly out of shot.
How Green Was My Thumb? - S3-E17
Visible crew/equipment: Just as Roy opens the door to Mrs. Johnson's apartment and he and Johnny walk in, the shadow of production equipment (looks like a reflector screen on a tripod) is visible on the wall behind them.
Visible crew/equipment: When the boy who ingested ant poison is being wheeled into treatment 3, in the shot from the hallway we can see the electrical cord and plug lying across the floor, but in the next shot from inside treatment 3, that cord has vanished.
Visible crew/equipment: At the horse ranch, after Bill falls off the horse again while the squad is chasing after him, when Roy kneels beside Bill we can see the shadow being cast by production equipment, presumably the reflector screen, on the ground behind Roy. Then after John checks Bill's ears and pulse, just as he contacts Rampart for the second time, we see movement which looks like a sleeve on the right side of the screen, beside John.
Visible crew/equipment: After Roy tells Jason that he has time to pop up to the orthopedic ward because it's Johnny's turn to cook, when Roy heads out receiving we can see the top of the set over treatment 1, right behind Johnny.
Visible crew/equipment: When Squad 51 arrives at Homer's house, we can see the outlines of the mic transmitter and wire on the back of the old cowboy's shirt.
How Green Was My Thumb? - S3-E17
Visible crew/equipment: When Johnny follows the nurse as she gets off the elevator on the fourth floor, the outlines of the mic transmitter and wire are visible on the back of the nurse's white uniform.
Visible crew/equipment: While Squad 51 is parked at ER receiving, John and Roy tell Dr. Early about the squad's engine problem, and when Early fixes the engine problem, we can see the reflection of numerous set lighting on the squad's chrome spotlight.
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.