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Re: Semaphores

John Kerley wrote:
> 
> Geoff Downes (Graphic Mountain Pty Ltd) <graphicmountain@bigpond.com> wrote
> in message MH0P5.41918$e5.54231@newsfeeds.bigpond.com">news:MH0P5.41918$e5.54231@newsfeeds.bigpond.com...
> > Thanks guys,
> > Victorian Semaphores are what I'm after - I am Victorian "biased".
> > Regards Geoff
> >
> >
> Well my Victorian Home arm is 142cm long (I only had a metric tape but if my
> calculations are correct this is 4'8" as reported by others) and 26cm wide
> with the white band 26-46cm from the square or outer end and the pivot point
> 65cm from the outer end.  This I found rather interesting as it means that
> on somersault arms, the pivot is closer to the outer rather than the inner
> end of the arm, quite a contrast to other types of semaphores.
> 
> Cheers,
> 
> John Kerley

G'day John & all,

As to the pivot being closer to the outer end of the arm. I think you
will find that the reason for this is to aid in its return to Stop
(horizontal) should a signal wire break. That way, the design itself
works towards the "Fail - Safe" principle.

Cheers and LINE CLEAR,
Chris. F.
-- 
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