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TV Remote Controls. TV
remote controls have been around since 1950. Zenith was the first
company to market this product. This remote control was wired to the
TV. You could change channels, turn the sound on and off and also turn
the TV on and off. You could not adjust the volume up or down.
In 1955, Zenith introduced Ultra Sound. This TV remote control was
a box that could generate sounds just above the range of human hearing
(30 to 50 kilohertz). Because it was above 30 kilohertz, no one could
hear it. The TV had a microphone that could pick up these frequencies
and the circuits that processed them. If you pressed the "ON" button,
it would generate a frequency and the TV would decode it and turn the
TV on. This was limited to only four or five keys. Ultra Sound was in
production for over twenty five years.
In 1975, the infra-red TV remote control began to take over. In
1980, almost everything was using infra-red. These remote controls
would send an infra-red signal to the TV. Infra-red is very
programable, but it can not got through walls or floors and has a range
of about three to eight meters. With infra-red, the sky is the limit
for the number buttons on the remote. Today, we still use infra-red
today on most of our remote controls. Some remotes use radio
frequencies, but this method is more expensive to manufacture. We offer
TV remote controls for most major brands.
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