pedestrian crossing control

[myths999]

On the base of most controllers, there is a knurled knob.
Anybody know what this is for?

[hc4361]

Yes, it is for blind people. The knob turns when the lights change.

[hc4361]

Facilities for blind or partially sighted pedestrians
Single crossing usually have a bleeper to help blind or partially sighted people know when it is safe to cross. These are not installed on dual crossings as a blind person could hear the far crossings bleeper and think it was safe to cross. In this situation blind pedestrians should use the tactile cone - virtually all signalled pedestrian crossings have a rotating knob underneath the WAIT box, which turns when the green man lights up.

http://www.leeds.gov....crossing_signals.aspx

[sunny-dave]

Well I never knew that !!

[myths999]

Thanks to you both. Wouldn't have slept tonight!