What key technological component powered early mass-produced automotive speedometers?

Answer

A flexible shaft connected to the transmission or wheel hub

The functional mechanism that powered early mass-produced speedometers involved a flexible shaft connected to the transmission or wheel hub, which spun a magnet inside the casing.

What key technological component powered early mass-produced automotive speedometers?

#Videos

Frank Jansa and the history of the speedometer and odometer by ...

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