Looking at a second hand unit with this data:

Operation 9x10
Drum Run 3x10
Tape Run 2X10
Threading 5X10

Is Operation - number of hours powered on and drum time recording etc?

Thank you

Operation is the total amount of time the camera has been powered on, regardless of what it was or wasn't doing.

The other numbers break down the various parts of the camera's operational time.

Drum run would be how many hours the tape drum (heads) have been spinning.

Tape run would be how many hours the capstan has been pulling tape across the spinning drum.

Threading may be a count of how many times the tape mechanism has threaded the tape over the drum.

Since the mechanical parts of the tape mechanism are the most prone to failure due to wear and tear, these meters can tell you when to have maintenance done, or they tell a prospective buyer how much use the camera has had.

Taken collectively, they reveal much the same information as your car's odometer.

-gb-