First time in a TV show
In 2019, our Zen nixie clock appeared in episode 6 of season 1 of Project Blue Book.
This is a historical, mystery series set in the Cold War and atomic era, inspired by a real U.S. Air Force program "Project Blue Book" that was interested in UFO. The main character puts himself in danger because of his investigation, and also his family.
Nixie's clock can be spotted in a thrilling scene when the countdown to the launch of a nuclear missile at the actual military landing site spontaneously clicks.