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Sunday, December 31, 2017

Conemaugh Line Cab Signal Expansion

In what could pass for a piece of positive signaling news these days, Norfolk Southern is actually expanding it's Cab Signal System territory by installing cabs on the former PRR/Conrail Conemaugh Line between CP-KISKI and either CP-ETNA or CP-PENN.  For those who didn't know, the Conemaugh Line, a low grade main line running along the Conemaugh River between Johnstown and Pittsburgh, PA, was used by the PRR to test the concept of using cab signals without fixed wayside signals.  The system was installed between what is now CP-CONPIT on the Pittsburgh Line and CP-KIKSI, where the line had a wye junction with the Allegheny River line into the oil and coal fields on Western, PA.  Because the PRR did not want to equip these Western PA pool engines with cab signals, the remainder of the Conemaugh Line was conventionally signaled.

Westbound signals at CP-CONPIT with the original Rule 280b 'C' lamps installed.
While Conrail expanded it's cab signal territory in the 90's, adding the Boston Line, and the Fort Wayne/Cleveland Line corridor between Conway Yard and Cleveland, NS has been content with the status quo, perhaps in spite or because of the PTC mandate.  Plans to convert the Port Road and Pittsburgh Lines to waysideless operation did represent one type of change, it would not actually add any additional CSS track miles.

Same cab signals, just different packaging.
Well while I was in Pittsburgh recently I popped byCP-SHARP, which had been rebuilt from its Penn Central predecessor along with CP-ETNA as part of a siding expansion project.  You could say I was surprised when I saw new signals going up with the telltale 'C' lamps on them, indicating that since the Oil City line was long abandoned, NS saw no reason not to bring its cab signaled trains all the way to Pittsburgh on the alternate route.

As you can see the new 'C' equipped mast will lack the third head included on the existing mast as Medium Approach Medium is not considered necessary where a cab signal can be held at Approach Medium after a train diverges over Medium Clear.  This is one of the few circumstances where a PTC related re-signaling project has actually brought about more interesting signaling.

While I was not able to stop by CP-ETNA to see if the Rule 562 operation stopped there or would continue to CP-PENN, I suspect it will stop at ETNA, at least until the Conway Corridor is fully re-signaled.

Wednesday, December 27, 2017

No More Lehigh Valley Signals on the Lehigh Line

Just got back from a road trip and to my disappointment I discovered that the remaining Lehigh Valley RR signals had been removed from the lower half of the Lehigh Line between CP-67 and Bethlehem, PA.  Caught up in this sweep were the former CNJ/Reading interlockings of CP-ALLEN, CP-CANAL and CP-JU (previously re-signaled by Conrail).  

The project had been underway for well over a year and I had taken the opportunity to document as much as I could, however I missed the two LVRR automatic signal locations at MP 71 and MP 74 as when I passed them by last October they did not appear to be under threat.

Of course the most devastating loss will be the classic LVRR Gantryleaver signal at the site of the former Easton, PA station.  This stout structure was in no structural danger and had been upgraded over the years with railings and walkways, but it appears that NS's commitment to its heritage is limited to more PR friendly devices like locomotives :-(

The former CP-RICHARDS was replaced by a new crossover a few miles to the west as once again the block lengths were stretched to reduce the number of signaling locations. Rule 251 was then replaced by 261 between CP-RICHARDS and CP-BETHLEHEM.  

I was also disappointed to have missed documenting CP-JU.  Although the original CJU plant with pneumatic points and signal bridges had been replaced by Conrail, it was nevertheless a great example of Conrail signaling, complete with searchlight dwarfs.

Finally, the odd arrangement between CP-EASTON and CP-PHILLIPSBURG wherein trains crossing the Delaware River could not get an Approach indication.  Signals would only display Clear or Restricting for following movements.  This was possibly due to some previous restriction regarding trains being stopped on the bridge, however NS appears to have remedied the problem and trains can get Approach at both locations.  I should also mention that CP-PHILLIPSBURG had already gotten new Darth Vader signals installed within the last 5 years for...reasons.

This is yet another lesson about not taking things for granted.  If you have the oppurtunity to photo something, do it ASAP, even if you think you'll have time enough to catch them "later".  If you would to see what I was able to document my Lehigh Line Amtrak Autumn Express photos can be found here and my Easton Roadtrip photos cam be found here.

Wednesday, December 20, 2017

The Sounds of PRR Signaling

This topic has come up a few times in other articles, but one of the neat things about non-solid state signaling technologies are the sounds.  Relays click, air hisses, motor generators....motor-generate?  One of the things I try to do on my documentary trips is capture any interesting sounds that might be escaping from one of the old relay huts or air plants.  My digital camera takes video just as well as stills so it doesn't take much extra effort and I then assemble the results into compilation videos for YouTube.

The following videos were taken mostly along the PRR Main Line or some of its connecting branches.  The sounds can be broken down into the following categories.

Air Hiss: Where switch points are operated by air, there is always a hissing leak somewhere.  Always.

Compressor Chug: When the pressure gets low enough, a compressor trips on.

Something Turning: Motor generators  or flashing relays typically have rotating parts.  When they get worn out, you can hear them.

Cab Signal Code Generators:  The most common sound I capture, electro-mechanical CSS generators generate pulses of current between 1 and 3 times a second. Code rates are 70 pulses per minute for Approach, 120ppm for Approach Medium and 180ppm for Clear. Generators are typically only active when code is being supplied.

The sounds are pretty self explanatory so I won't go into much detail.  Part of the fun is trying to determine which cab signal codes you can hear or what that rotating thing is doing inside the relay cabinet.

In the first video we have sounds from:

MP 53.1 signal on the Enola Branch in Cly, PA
CP-JEB on the Royalton Branch
ALTO interlocking in Altoona, PA
CP-SLOPE in Altoona, PA
MP 277 automatic signals at Fostoria, PA.

In the second video we have sounds from:

CP-PORT in Newport, PA
MP 131 automatic signals
MP 142 automatic signals
CP-MIFFLIN in Mifflin, PA
CP-HAWSTONE near Lewistown, PA

Anf finally in the third video we have:

MP 124 automatic signals
MP 196 automatic signals
HOLMES Interlocking, Holmesburg, PA

As you can see, "noisy" signaling components were installed up through the 1980's, but since then there was been a pretty much wholesale move to solid state.  After all, pulsing current is pretty much the hallmark of of what semiconductors can do :-\

Monday, December 11, 2017

A Great Early CTC Resource!

As the few remaining stretches of classic CTC signal gets ground under in favor of lifeless Darth Vaders and wireless links, sometimes I find myself at a loss for information when writing up trip reports or signaling articles.  Were the signals installed in the 50's?  The 60's?  Were they controlled from nearby towers?  Dispatching offices? How much has the territory and layout changed since it went in?  Getting access to the interlocking sheets from somewhere like Multimodalways is the gold standard, but their collection is largely incomplete, pretty much restricted to the Northeast united States.

Then I happened to take a second look at's archive of classic signaling photos and I noticed that not only did they have an extensive factory photo archive of classic US&S CTC consoles, but the photos had enough resolution to actually read the model boards and level labels.  Best of all, the photos cover railroads across North America, from the Reading system to the C&O to the CB&Q.  For example, in 2010 the CTC console in the former Reading Railroad TRENT tower looked like this:

As you can see, it's not very helpful.  However's factory photo reveals all the details including a date of 1954.  

The first generation CTC era of railroads was both visible and invisible.  Visible because the signals and relay-interlockings lasted well into the 21st century.  Invisible because the consoles were hidden away in towers and offices long since shipped out to the scrap yard. This archive of photos provides real insight into what was happening to North American signaling after the heyday of the single interlocking tower.  Personally I was quite surprise how early many of the installations were as my assumption had always been the 1960's instead of the 1940's or 50's.  This is probably due to the PRR being a notorious "late adopter" of CTC.

Monday, December 4, 2017

Fall 2017 Reading and Northern Update

So I just got another e-mail from Bill Tarantino in the year since his last update, the R&N has extended its CTC south from Tamaqua towards the shoppe complex at Port Clinton. This segment was placed into service on 09/13/2017.   It consists of 2 new interlockings and 4 sets of twin mast paired directional ABS in between.  Rule 261/CTC now in effect from MP 78.8 (CP CLINT) to MP 105.3 (CP HAUCKS).  All CTC is currently from Port Clinton.  However, operations are expected to be transferred to the new North Reading Tower next year.  I guess that means we'll have a brand new interlocking tower to add to the active list :-)

The new interlockings south of Tamaqua are CP-EQUILATERAL (MP 95.2) and CP CLINT (MP 78.2).  CP-EQUILATERAL is the end of the Tamaqua siding at the site of the old Reading MYRTLE interlocking and CP-CLINT is the entrance to the Rule261 track north of the non-signaled yard complex.

 Bill wrote about the new interlockings:
However, much to my continued puzzlement, the northbound home signal at CP EQUILATERAL like the southbound CP TAMAQUA home signal is a triple head 9 light wired unit capable of displaying all NORAC aspects.  Can’t understand the need for these triples deployment per requirements for right now.   Tamaqua end is somewhat understandable  with a single slow speed 15 mph switch into either the yard or dark territory branch for R/R/G or R/R/Y aspect but why the real need for the middle head then when R/Y would do?   Similarly, Equilateral end is a medium speed Y switch for dual main routing only so why the need for a 3 light lower head.  R/G/R or R/R/Y should suffice. Currently, doesn’t make sense.  Also, at Equilateral, the southbound home signal adjacent to the now passing track is a dual head mast signal and old main track 1 gets the dwarf application.  This arrangement suggests track 2 will soon be employed as the new southbound main at some point but there is no new interlocking at either MBS MIDDLE YARD or MBS LOWER YARD to automatically get trains from the single main track 1 onto track 2 as a routine passing siding application.  I just can’t imagine this will continue to be a manual operation with ongoing track upgrade work and those additional heads.  The only scenario that makes sense for these deployments is an additional new interlocking for MIDDLE YARD or LOWER YARD.  Then, Tamaqua and Equilateral can display various appropriate approach aspects using all 3 heads like Y/R/G.   We shall see.

 It will be interesting to see how the Port Clinton complex just to the south gets treated and signaled.   Andy Muller had those old black multi track truss signal bridges put in place bounding the old RDG Port Clinton Interlocking when they were building out he complex.  But, more complex trackage has since been added.  Just the single diversionary route switch between the Tamaqua and Pottsville Branches is currently powered and controlled from within the PC Tower Office.   But, is not governed by any signaling to date.  Also, wondering if they employ the same treatment shortly before MP 77 where MBS KERNS begins the northbound double track into Port Clinton YL. So, this will all be interesting to follow as well.

Steam friendly right hand mounted paired mast ABS locations along the Little Schuylkill Branch are at MP 91.5, MP 87.7, MP  84.4, MP 81.1.   All are single head type tri-lights with the exception of the south and north bound approach distant signals to CLINT and EQUILATERAL.   These are dual head type G’s for approach aspects.    Also, of interesting note, the ABS at 91.5 are solar powered due to the remote isolated location and lack of a readily available power supply.   

Unfortunately many of the new signal heads are off the modular SafeTrain type, instead of classic US&S TR's or GRS G's or even newer singe housing tri-lights.  However this appears to be an availability issue as this off-brand tri-light was spotted at MP 87.7 and the signals at CP-CLINT are indeed of the classic type.

More importantly a Reading style sideways 2-lamp signal head was placed at MP 84.4.

Apparently some of the ABS signals are displaying an un-Reading *Y* for Advance Approach instead of Y/Y, but I'm not going to complain. I suspect that as the passenger service to North Reading ramps up, the signaling will eventually make its way down in that direction.

Thanks again to Bill for all these great updates.  I'm sure I'll make it out there myself one of these days.  However unlike most signaling emergencies, this one is only going to get better, instead of worse :-)