The phrase "a stopwatch at" is correct and usable in written English.
It can be used when referring to a specific time or event that is being measured or timed with a stopwatch.
Example: "I started the race and had a stopwatch at my side to track my time."
Alternatives: "a timer at" or "a clock at".
On a recent morning, a stopwatch at his side, he bent his back over a stool, his fingertips and toes touching the floor.
At the moment when they pictured their release from the top, they were to press the start button on a stopwatch; at the time that they imagined hitting the net, they were to press the stop button.
The time in second (s) for tail withdrawal from the water was taken as the reaction time and recoded by a stopwatch at before (0 min) and after 30, 60 and 90 min the administration of test samples.
The consultation length was measured using a stopwatch, starting at the first verbal expression and stopping after the last verbal expression.
Find a place to do homework, make sure supplies are ready, and have a stopwatch available at all times.
And I don't see a lot of consumers in their restaurants standing around with a stopwatch and yelling at store employees that they were two seconds slower in serving their Big Mac.
A record of all solutions and disposables was kept and a stopwatch was kept at each bed and each time the TPN needed attention.
Sadness can lead to a deceleration of time, and so can fear, as the neuroscientist David Eagleman confirmed when he dropped his subjects from a tower at an amusement park in Houston, each participant instructed to stare at a stopwatch in free fall until being caught by a net.
Williams, who would rather have been playing tennis, would sit grumpily at home Sunday afternoons looking at football, a stopwatch in one hand, a telephone near the other, so he could keep in touch with CBS Sports and also with Merri Lieberthal, his coördinating producer, who was up on West Fifty-seventh Street. Fifty-seventh Street
The experimenter employed a stopwatch to note the time at which the counter was turned over, and whether it was in the green or red zone.
Mr. Pressman said he would bring a stopwatch to his third-floor studio at Rockefeller Center to make sure that no candidate talked too much.
