Dr Zarkoff Wrote:
-------------------------------------------------------
> You were a passenger, a casual observer. I'm
> speaking from an operating employee's point of
> view. There are certain circumstances under the
> Rules where visual inspection of blocks is
> permitted, however, if the signals aren't Clear
> (i.e. "green"), you can't, or rather aren't
> permitted to, make any assumptions about what is
> causing the yellow signal other than a train
> approaching your location.

Not sure what you're trying to prove. I never asked the question in the context of rules compliance. It's not like we were entering the main at a hand-throw switch and looking for a way out of waiting 5 minutes.

I can't think of any scenario (other than curiosity) why an operating employee -- on a moving train, travelling in the direction authorized -- would need to be concerned with the opposing signals being displayed behind their train.


> As I've posted elsewhere in this thread, there
> isn't sufficient information available today as to
> what characteristic of the signal system's
> circuitry may have kept those signals you saw in
> the Approach ("yellow") position.

Did you see where I explained that my SP friends, who had worked south out of SLO for many years by that point, said it was normal behavior for those ABS signals? They had seen the same thing thousands of times...

UP finally upgraded the signals a few years ago, but the old design had lots of staggered signals and inconsistent block lengths. Lots of short 1-mile blocks. Some of the sidings had (maybe still have?) non-controlled absolute signals.