This is a
close-up of the speed display. Each display number is
composed of eight plastic display pieces. Each display piece
has a bright yellow side. A spring causes the display piece
to turn edge on so that the yellow side is normally not visible.
When a
speed is registered, by the radar unit, a signal is transmitted to
the display. Electromagnets in the display are activated;
display pieces present their yellow sides, and the numbers
reporting the speed are visible.
