The Zenith Space Command TV remote was introduced in the 1950s. It used ultrasonic sound waves instead of infrared (IR) or batteries. Each button activated a small hammer inside the remote, striking metal bars tuned to specific frequencies. These ultrasonic sounds were picked up by the TV to perform basic functions like changing channels or adjusting volume.
I'm old, but not that old! Now, Barry may remember that remote
Boy David you really made me feel old,not only do I remember it, we had it. And it was a very funny circumstance. we lived in an apartment building next to the elevator. when someone on our floor rang for the elevator, a high-pitched beep, went off and not only diid it summon in the elevator, it changed our channel. so it was a little bit annoying at the time. And this was the early 1960s.
Barry, somehow I knew you would have experience with this! The elevator must have had a bad ground wire or something to send out enough of a signal to change you TV channel. PS - Sorry to make you feel old Barry, but I hate to break it to you, but you are old
The elevator let out a loud high pitch “ping.’’ That loud sound changed the channel. Was it an era before you could have a DVR. so you would get to final Jeopardy, “ and the answer is…” and the channel will change. and you would never know the answer.