U.S. signaling questions?

[signalmaintainer]

Where ever did you find that? Is that in the old car shed in Yakima? It's a mechanically activated block signal from the old Yakima Valley Transportation line. The indicator arm is shown in the "block ahead occupied" position.

 

A car or locomotive on the YVT entering a block would trip a wire, causing the indicator arm to drop. A following car or locomotive would then know the block ahead was occupied by a car moving in the same direction and would proceed prepared to stop.

 

At the other end of the block, the indicator arm for the signal governing movement the other way would move to horizontal, showing a car is approaching.

 

If no cars were in a block, the indicator arm would rest between horizontal and vertical.

 

Oh, and if I sound like I really know what I'm talking about, I can thank a clue provided in the photo above. It shows page 73 of Kenneth G. Johnsen's excellent book on the YVT, "Apple Country Interurban." What I wrote above in the paragraphs two through four is his explanation.

[298]

That's right Paul, couldn't have explained it any better myself...! It was in the Yakima Carbarn, they might have it on display somewhere else now.

[signalmaintainer]

I need to get over to Yakima again, Andy. It's been quite some time since I've seen Line Car A and the steeplecabs. 'Course, your Wiley City layout always gives me a sense of deja vu!

[JWB]

There are prototypes for everything. Although as a general rule there aren't signals in prototype switching areas, here are a couple of exceptions. The first is an odd signal on the Modesto & Empire Traction, a California short line that is very busy (normally two jobs per shift, three shifts per day).As far as I can see, it's some sort of a glorified switch indicator, since the switch is remotely activated. I've seen several signals like this on the M&ET. The Ventura County Railroad, another shortline that isn't as busy, has signals that look like small two-light block signals. I'm not sure what they're for, and I will get photos the next time I'm up there.

 

The second is a dwarf signal on the UP's line down Downey Road in Los Angeles, near where it interchanges with the Los Angeles Junction. The Downey Road line itself has interlocking signals where it crosses BNSF and other lines, and I'm not sure if it has block signals otherwise. The signal here is for an industrial spur next to a highway crossing, and while the signal seems to be a standard dwarf, it flashes red in coordination with the crossing flashers.