On Mon, 05 Aug 2019 12:03:52 +0100, Daniel James 
declaimed the following:

>In article , Dennis Lee
>Bieber wrote:
>> Remotes of that period had just two buttons... Power and Volume.
>> And volume tended to be "mute, low, medium, high" IN SEQUENCE.
>>
>> And the remote functioned by sending an ultrasonic whistle chirp ...
>
>Wow. Fascinating. Thanks.
>

https://patents.google.com/patent/US3102509

... though I distinctly recall my grandfather's TV having two buttons on
the remote.


--
 Wulfraed                 Dennis Lee Bieber         AF6VN
 wlfraed@ix.netcom.com    http://wlfraed.microdiversity.freeddns.org/

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