"Basil Jet" wrote in message
news

Geoff's latest video...
https://www.youtube.com/watch?v=2aP2rMRO_WA
... shows a couple of WHISTLE boards in the vicinity of the Watford Met
Branch triangle. Why are these locations singled out for whistling? How
many whistle points exist on the tube? Wouldn't a fixed whistle activated
by the presence of a train be a better solution?
Not just there on the Met. IIRC there also used to be whistle boards just
before platforms which could be used by stoppers and non-stoppers. The
aim's the same as the ones you've noted. To warn those who might not be
aware of their predicament.
PA