This early TV remote worked without a battery

[commasense]

In addition to the tuning fork type, there were also remotes with ultrasonic whistles.

Without saying your age, what's something from your childhood that a younger person wouldn't understand?

Hah! Although I thought it was a Zenith, I was wrong. I found the exact model remote she had. It was an Admiral. When I learned that Zenith used tuning forks, not whistles, I began to doubt myself. I’m pleased to see I’m not going crazy. (Or, at least, that this is not evidence of it.)