[PRCo] Signalling

[Jim Holland]

Good Morning!

	Probably a question for FWS3.......

	How did the impedance bond in the US&S signalling work?    How did it
allow ground to pass while blocking signal voltage?    Axles short out
low-voltage current to run signals, correct, which causes red board?   
Failure of the low-voltage current automatically set all signals red,
correct?

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James B. Holland

Holland  Electric  Railway  Operation....... 
___"O"--Scale St.-Petersburg Trams Company Trolleycars and...
______"O"--Scale  Parts  mailto:pghpcc at pacbell.net

______Pennsylvania Trolley Museum http://www.pa-trolley.org/
___Pittsburgh  Railways  Company  (PRCo),   1930  --  1950
N.M.R.A.  Life member #2190; http://www.nmra.org

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