Signalling -- SHJ

[Jim Holland]

Greetings!

Fred W. Schneider III wrote:

> Was this a weight limit or simply spacing signals to prevent accidents
> in the event of a fog?

> The same signals went all the way down through South Hills yard and
> there wasn't a weight problem there.

	You know what amazes me - South Hills Jct. under PRCo had a myriad of
turnouts, routes, turns, crossings, and the only signalling was at the
mouth of the tunnel!
	In one of the videos on  ({[pat]}) probably not too long before the
rebuilding of SHJ, the cameraman is standing near the old 40-line
turnout filming toward the north.  An outbound interurban crosses the
scene, followed by an outbound 42/38 followed by a car crossing all this
outbound from behind the admin building followed by other cars crossing
inbound.  This is not a series of shots or cuts to make a scene  --  it
is all naturally flowing movement.
	With the modern computer controlled systems of today that preset
turnouts and control blocks etc., SHJ would be a nightmare of delays
with the track layout from old PRCo days - nothing would get through! 
But it all worked so smoothly under PRCo with only a bare minimum of
delay.

James B. Holland

        Pittsburgh  Railways  Company  (PRCo),   1930  --  1950
    To e-mail privately, please click here: mailto:pghpcc at pacbell.net
N.M.R.A.  Life member #2190; http://www.mcs.net:80/~weyand/nmra/