The Zenith Space Command, one of the first wireless television remotes ever to exist.
Weird I think I saw a YT video explaing it and this is the info I remembered
Looks like it’s a bit of both: while they did work by emitting an ultrasonic frequency, they also made an audible click. https://www.theverge.com/23810061/zenith-space-command-remote-control-button-of-the-month
I feel like there’s a technology connections video on the topic but I could be hallucinating