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Wednesday, October 18, 2017

HAMILTON Closes and Other Bad News

I just learned from a contributor that the famed B&O CPLs at HAMILTON interlocking in Hamilton, OH were cut over this past weekend.  One can also assume that surrounding CPLs have also been replaced.  Unlike the Broadway show there will be no touring production.

In other bad news, replacement signals have gone up at CP-ROCKVILLE and CP-HARRIS, which so far has seemed immune from NS's PRR Main Line signaling blitz.  The "new" PRR PLs at Rockville will be an especially hard loss.  The signaling dates from the late 1980's.

I can also report that the pneumatic point machines have been replaced by electric M23's at CP-HUNT and on the former N&W H-Line, the last bunch of PLs on the northern segment have also fallen. 

Finally, the new signals at CP-ALLEN have cut over, replacing former Reading searchlights.  Status of the eastern Reading Line Rule 251 ABS is unknown at this point.

Wednesday, October 11, 2017

METRA Cab Ride Videos Courtesy METRA

The METRA commuter rail network has been seeing a lot of re-signaling as of late, but there is still a lot of interesting stuff out there like searchlight signals, CNW signal bridges, ATS shoes, Rule 251 operation and a few open and closed interlocking towers.  Thanks to METRA's use of gallery cars there are quite a few railfan window videos from METRA trains floating about on YouTube, however earlier this year a new source came on the scene, METRA itself.

Taking a cue from Chicago's CTA, METRA has embarked on a project of creating HD head end videos of all its major commuter routes, both inbound and outbound. While they aren't the most exciting (no effort was made to video express runs) they do capture the current state of the signaling hardware as well as live signal behavior (as opposed to everything just displaying Stop).

The videos are going up every few weeks.  I am looking forward to the UP West and UP North lines as both of those have a lot of surviving CNW features as well as ABS operation. 

Wednesday, October 4, 2017

PRR LAMOKIN Tower Demolished

I am sad to report that one of the least visible (and least structurally sound) towers on the NEC was just swept into the landfill of history.  LAMOKIN was located at the junction of the old PRR Chester Creek Branch between the presend day BALDWIN and HOOK interlockings.  LAMOKIN was closed in 1972 when the lightly used Chester Creek Branch was done in by Hurricane Agnes.  Since then it has sat, decaying, along side the NEC,hidden from the north by the equally historic Lloyd St Bridge.

The tower, built as near as I can tell around 1900, is similar to PAOLI, BRYN MAWR and CLY with a brick base and a wooden operating floor.  The slate roof had completely deteriorated and it was only a matter of time until the tower burned down or collapsed.  When it was open the tower controlled a trailing point ladder that allowed access to the Chester Creek branch to and from the north.  The machine was an electro-pneumatic type and you can see the remains of the air plant in the above photo.

As I rarely had a reason to be in the area I never got a good set of photos of the tower and although I passed by on Amtrak many times a year, it was always out of sight and out of mind.  Just poignant reminder to always get photos of interesting things while you can.

LAMOKIN in 2002, still showing its PC Green and a bit more roof.
Ultimately it appears that the demise of the tower was prompted by the demolition of the adjacent Lloyd St bridge as it was simply prudent to demolish both at the same time.  All that remains is a patch of crushed grey stone.  Oddly enough, the tower has its own Wikipedia page.  Looks like I'll have to update it :-\

Tuesday, September 26, 2017

Some NS News

I had a couple of NS signal alerts I wanted to share.  The first is that apparently the cut over on the Ohio portions of the Nickle Plate Line is fast approaching so go get your photos while you can.

I also heard that new signals are now up at CP-CANAL and CP-JU on the Reading Line, east of Allentown Yard.  On my previous trip back in May, both of those interlocking were as up yet untouched.

Finally over on the PRR Main Line I was documenting the old signals at CP-BANKS and I noticed some interesting with the new signals and how it might fit in with the Rule 562 operation.  Currently, all eastbound signals at CP-BANKS can display Approach Medium because it is back to back with CP-ROCKVILLE on track 2.  (The signals on Track 1 and the siding can display Approach Medium as per the Conrail practice of allowing trains to diverge over those indications if the previous signal gave proper warning of the first diverge.  Basically a poor man's Medium Approach Medium.)

The new eastbound NS signals set out for CP-BANKS are not set up for Medium Approach Medium on tracks 2 or the siding, nor is Approach Medium available for track 1.  I suspect that NS is using the new cab signal only operation to restore the additional block and improve capacity at modest cost.  In fact I have seen a number of new relay huts away from current signal locations or grade crossings so NS could be trying to actually get something out of the new signaling system apart from lower costs.

Wednesday, September 20, 2017

Call to the Signal Bungalow

So a number a years ago I was planning to get some signal photos along the former Conrail Buffalo Line and while searching for information on CP-NORTH MILLER, I noticed something strange about the results.

It appears that, for some bizarre reason, the telephone in the signal house at CP-NORTH MILLER had gotten itself listed in a phone book at some point and now it was plastered all over various cyber-leech clickbait websites.  Normally I might not have given this a second thought, but for another poignant experience I had way back in 2006.

On another Buffalo Line trip, while taking photos at CP-LINDEN out of the blue an old style bell phone began to ring inside the spacious 1950's vintage PRR CTC-style relay house.  I had a chuckle thinking who would be calling an interlocking in the middle of nowhere, but when I saw the phone listing for CP-NORTH MILLER 8 years later, I just HAD to try it.

The PRR was never very enthusiastic about CTC, content to rest on its laurels of multi-track main lines, manned block stations and the manual block system.  However it did green light a few projects and the Main Line between Rockville to Buffalo, was one such example.  Installed in 1957, the Buffalo Line CTC was definitely a creature of the PRR with lavish signal huts, a reliable power supply (so no approach lighting) and apparently, a PTSN station in each walk-in signal shanty.

So back in 2014 I drove up from Rockville to Millersburg, all excited about capturing a cool intersection of the rail and telephone network communities of interest and...nothing happened.  I tried the number and the phone didn't ring.  Ah well, should have known it wouldn't have worked.

Fast forward to 2017 and I was back up again, chasing signals on the Buffalo Line and I just couldn't help myself to pull over and see if I could give the call another go.  At this point I'll cut to the video.

Man, what ever happened to that wonderful rich 1950's ringer sound?  Absolutely wonderful!  I'm going to go out on a limb and say I'd bet it was a wall mounted Western Electric model 554.  I don't see the PRR sticking a desk set in such a cramped location, nor do I see Conrail or NS ever having upgraded the line for DTMF service ;-)  Of course a Western Electric rotary phone is probably even more reliable than the US&S glass case relays powering the interlocking logic. 

Wednesday, September 13, 2017

A British Style Tower In Illinois

In Europe, mechanical signaling is still quite common.  Paired with the manual block system, all or nearly all-mechanical interlocking towers control thousands of miles of main line track.  However in North America, the all-mechanical tower, that is with semaphore signals controlled directly by levers and pipeline, is virtually unheard of .  Yes examples can be found at drawbridges and diamond crossings on low density track, but the difference is quite stark.  Part of the reason is the general incompatibility of automatic block and mechanical signals.  Manual block was much less popular in North American than in Europe.  The other reason had to do with a number of ICC regulations that required signals to be interlocked with train detection (read track circuits) and that signals be electrically interlocked with point detectors.

You can imagine my surprise when I discovered Neilson Jct in Neilson, IL to have a set of fully mechanical signals controlling a manual block style junction with non-Restricted speed movements.  Now RR Signal Pics does a great job providing basic details about Neilson, but I just wanted to not only call attention to that page, but also to a set of videos that have been on Youtube since 2011, but due to poor use of keywords, does not appear on most interlocking tower or signaling related searches.

For a single switch between two secondary tracks, Neilson has a surprising number of levers.  First, just like in British practice, each former C&EI distant has its own lever.  Second, each of the southbound signals are connected to derails which also come with a facing point lock.  Finally, the 12 lever operated a mechanical timer that I assume provides approach locking in the absence of track circuits.

The northbound home signal handled the route route selection issue by having two semaphore heads, each controlled by a different lever and indicating one of the two routes.  Of course the straight route semaphore was for the C&EI and the lower diverging route semaphore for the BN.

Aside from the British style of operation, what really puzzles me is how such a tower survived up through 1989.  Checking Google Earth it appears the single junction switch was replaced by a hand operated type and that the line is un-signaled.

Basically just watch the 7 videos and read up on the RR Signal Pix page. I'm just trying to call attention to an historical oddity that is in need of some help with discoverability :-)

Tuesday, September 5, 2017

The Curtain Closes on IRT Signaling (Take 2)

One of my earliest posts for this blog back in 2011, covered the closing of the NYC Subway's E. 180th St interlocking tower.  This was the last instance of an electro-mechanical single interlocking tower on the IRT division and also what I thought at the time was the last bastion of old IRT signaling as well.  You see, in addition to it's on interlocking plant, E. 180th St tower also had CTC control of the (5) Dyre Ave line.  It seemed logical that closing the tower would be followed by a re-signaling of the Dyre.

Well it turns out I was wrong and the old IRT signaling on the Dyre persisted for another 6 years!  Unfortunately, I was just informed that the NYCTA would finally be concluding it's closure of the E. 180th extended enterprise by cutting in a new, bog standard IND style system on the Drye on or after Labour Day 2017.

If you want a full explanation of IRT and IND/BMT signaling, you can find it here, but the short explanation is that the IND/BMT system uses the upper head for block occupancy and the lower head for route.  So a G/Y signal would be Diverging Clear and Y/G would be Approach Straight.  The IRT used a more railroad style system with each head representing a different route.  R/G would be diverging clear, etc.  Basically something that would be familiar to almost any real world railroader.  The NYC Subway marked old IRT signals with a red number plate and outside of the Dyre they were last seen on the (2) and (4) lines in the Bronx up through the turn of the Millennium.

While I guess it was a good thing that these signals survived 6 more years that I had assumed, I'll definitely regret not taking the time to go up and see them beyond my last visit in 2009. 

Wednesday, August 30, 2017

Amtrak PERRY Area Changes

There are some changes afoot in the Perryville area on Amtrak's Northeast Corridor.  To start, about a month ago I received this rare bit of good news about changes to GRACE interlocking, which featured Amtrak's brief operational test of Conrail style tri-light signals.

Well turns out the experiment is over and Amtrak is replacing them with colorized position lights.  So thumbs up emoji!

Unfortunately, Amtrak isn't stopping there.  It turns out they are also replacing the main line dwarf and pedestal signals at PERRY interlocking with CzPL masts.  I have to assume this is motivated by the 562 project that was reported to be going in between PRINCE and RAGAN as the new mast have 'C' boards, however unless Amtrak is looking to expand track capacity with extra ABS blocks, the "Clear to Next Interlocking" indications are completely unnecessary as the  NEC between OAK and PRINCE is comprised entirely of back-to-back interlockings!  Did someone retire because you folks used to do this the right way with Rule 261 or Interlocking Rules replacing 562 in instances of back-to-back interlockings.

Maybe someone thought that a 'C' lamp couldn't be attached to a pedestal or dwarf signal, but Conrail had no problem fitting 'C' lamps to PL dwarfs at CP-MA on the Morrisville Line.

Since the new signals are being spliced in, not going up in parallel, the typical "testing in parallel to save money" does not apply.  No position lights are always nice, but IMHO these full sized masts just look ungainly.  In electrified territory the signals should be up on gantries or it just looks half assed.  WWPRRD!

Tuesday, August 22, 2017

The Axis Invades Baltimore

Some of you may have heard that the Baltimore Metro was installing a new CBTC signaling system in conjunction with its new order of 78 Breda (now owned by Hitachi) railcars.  This might be surprising as such systems tend to only be economically viable when extremely high throughput over 20tph is required.  Baltimore's 6tph service is more than adequately serviced by a traditional block system, but I figured that once again some non-technical administrator was fooled by a signal vendor.  However this weekend I learned that the situation is far worse.  Not only has the Maryland MTA guppied up for CBTC, but they have also opted to adopt a German style axle counter system for backup train detection without any track circuits, even within interlockings.

The Baltimore metro was constructed back in 1983 with a fairly typical audio frequency cab signal system with 6 speed codes.  Apparently they have not very little investment in renewing the system and 30 years later most of the impedance bonds are end of life and getting unreliable so they see an axle counter system as a way to cut costs.  Breda is under the same umbrella as Ansaldo STS, the Italian signaling company that bought US&S and now both operate under Hitachi. This enabled Hitachi to offer both the cars and signal system as a $400 million package deal, and Baltimore found it hard to say no.

Unfortunately use of a German style signal system without positive train detection may result in problems when the German railway culture is not important.  The Baltimore Metro will be blind to broken rails, floods and random vehicles rolling onto the main line.  Track workers will no longer be able to clip in a track circuit shunt to protect themselves.  In Germany the government spends freely on rail maintenance and employees tend to obey orders without question.  In the lower cost United States, it is only a matter of time before this budget system proves deadly.

Tuesday, August 15, 2017

CP-ROCHESTER - Back from the Dead?

So is CP-ROCHESTER back from the dead or is it just a zombie that NS will eventually shoot in the head.  For a little context, CP-ROCHESTER in Rochester, PA was a junction of three former Conrail "Lines", the Fort Wayne Line, the Cleveland Line and the Youngstown Line.  A 4-track partial crossover, CP-ROCHESTER took the 4 track Fort Wayne line in from the east and spit a 2 track Fort Wayne line sandwitching a 2 track Youngstown Line, all while the Cleveland Line branched out to the side.   CP-ROCHESTER had always been a bit of a pain because it was not a 4-track complete crossover with only a complete facing ladder and two disjoint facing crossovers. 

CP-ROCHESTER is as much a mix of signals as it is a mix of lines.  When the old tower was closed in the 1990's, Conrail worked to re-use as much hardware as it could.  The westbound PRR signal bridge with two high PL signals was retained, however 261 operation on all 4 track necessitated the old reverse direction pot signals be upgraded to Conrail special 4-lamp dwarfs (GGYR).  Eastbound trains a new tubular Conrail cantilever and dwarfs and Cleveland line trains got a couple ratty looking color light masts.

Years ago NS single tracked the Youngstown Line and constructed a new CP-BRIGHT about two miles west of CP-ROCHESTER where the two main tracks could go to one.   The interlocking was just a single turnout and located solely on the Youngstown Line, however this gave some people ideas and about 9 months ago CP-BRIGHT was expanded into a 4-track full crossover and the new split point between the Fort Wayne and Youngstown lines.  The intention was to then remove CP-ROCHESTER except for the Cleveland Line turnouts, however this plan was postponed as dispatchers have found it exceedingly useful to store Conway Yard bound trains in the new pocket tracks created by the back-to-back interlockings.  It also allows for all sorts of paralel movements.

Needless to say, CP-ROCHESTER and its Conrail/PRR heritage is still extremely endangered.  I'd advise anyone in the area to get out and document it ASAP.

Fun Fact:  I had always wondered why Conrail had installed GRS point machines at CP-ROCHESTER and CP-WEST CONWAY instead of their usual US&S M3 fare.  However then I saw that each of the towers there had used GRS Model 2 interlocking machines, a real rarity for the Pensy.

Tuesday, August 8, 2017

DOLTON JCT Tower Closed and Demolished (1897-2017)

Well the inevitable finally happened.  The last all-big-lever interlocking tower in North America was not only taken out of service, but razed to the ground.  DOLTON JCT and its 172-lever S&F machine was built by the PRR in 1897 (and possibly rebuilt in 1944). The squat wooden structure was built to accommodate an Improved Saxby and Farmer pattern frame with a giant horizontal locking bed.

 A typical Chicagoland flat junction with more diamonds than turnouts, DOLTON JCT controlled the east end of the large B&OCT / IHB yard complexes.  In 1942 the tower had 136 active levers, decreasing to 100 in 1944 and the number has only gotten smaller and smaller since then.  when I Was able to visit in 2014, new owner IHB had started the process of chipping away the territory into new, independent sub-interlockings.

Apparently, the interlocking was cut over to the IHB dispatcher on February 27th, 2017 and then the tower itself was finally knocked down on Friday, August 4th in order to make way for a track realignment project.  Hopefully, like the IHB CALUMET tower that was closed in early 2016, local preservation groups were given the opportunity to save artifacts and what was in all likelihood, the largest mechanical lever frame still in existence in the western hemisphere.

 For full coverage of the last years of Dolton Junction tower and its ultimate demise, including a bevy of interior photos, check out the Industrial Scenery blog.

Also, as I mentioned before, John Roma has a number of additional interior photos posted at: ... 973032939/

Monday, July 31, 2017

Reading Country News

Just a brief news post.  I can report that the last remaining 1950's vintage signaling on the former Conrail Reading line, including CP-WEST LAUREL and CP-LAUREL, has been deactivated as of a couple weeks ago.  The section of ABS 251 between CP-BLANDON and CP-ALLEN remains intact for the time being.  Fortunately I paid a visit to these vintage interlockings around Thanksgiving of last year.  They had been part of the GRS provided Reading area CTC project that had been installed along with the Blandon Low Grade line. You can read about my documentary visit here.

Meanwhile, out on the New York Branch, CP-WOODBOURNE has also has its signals replaced (although possibly not resignaled outright given the old Conrail relay hut is still in use.)  This was probably part of the same project that hit the Conrail signals at CP-BERRY, CP-NESH, CP-FAIRLESS JCT and even the 1990's Conrail signaled CP-RIVER and CP-BELMONT.  At this point the Trenton Line can pretty much be considered an extension of the A-Line.

Interestingly, it appears that CSX is one of the last railroads clinging to Safetran Unilens signals As I previously reported, a number of design flaws has parked their neo-Searchlights for replacement on most railroad....except CSX.  For example, Caltrain is the latest road to retrofit their Unilens signals with LEDs.  Not sure if these specific examples at the San Jose Diridon Station are 3-color or just flash *R* Restricting, but its a major rebuke of the type.

I actually have one other major bit of positive news to report, but I'm going to save it for its own post. ;-)

Wednesday, July 26, 2017

Signal Transformers: More than Meets the Eye

In the beginning, before local power utilities were a thing, signals were powered by storage batteries placed in concrete wells at the base of the signal (or perhaps the basement of the interlocking tower).  Every so often some workers would have to come around to replace the batteries, taking the old ones to be recharged. This is why searchlights and semaphores were so popular.  Low wattage bulbs and track circuits could last for months on a charge, but it was still a labor intensive operation.  Railroads and their newfangled electric signals needed a reliable source of power and rural electric light plants that only ran from 6-9pm simple weren't going to cut it.

The solution was for railroads to become their own utilities and to string AC power lines on the pole line that was already carrying the telegraph and signal wires.  The simplest (and most popular) form of this was a 440-480v twin wire setup running on the outer position of the lowest group of wires (where it was least likely to drop into low voltage DC C&S lines).

Of course one can't just plug medium voltage AC into low voltage DC relays and expect it to work.  For this one needs a transformer and at every signal location along the line one was usually supplied on the pole to avoid bringing the 440 into the sensitive relay cabinets.  The transformers aren't very big, and its easy to not even notice they are there.  This example, on the B&O main line, likely dates from the 1950's or earlier. The 440v supply passes through two ceramic fuses so that the specific signal location can be isolated. 

On the opposite end of the spectrum, here is a modern style signal power transformer supplied by the Olsun corporation in 2003.  The AC-DC rectifiers are located in the relay cabinet or hut.  

The next level of signal power supply involved a single or three AC feed in the kilovolt range.  These were typically employed by wealthier eastern railroads with multi-track main lines and interlockings that could draw a lot of power.  Of course higher voltages required larger transformers.  Basically something on the order of what would be seen on residential utility poles.  This retired three phase example was found on the N&W H-line running north out of Roanoke.

This active example was encountered at CP-SLOPE on the former PRR main line back in 2012.  It had been installed before PCB's were banned in the 70's and has a big yellow sticker to that effect.

With transformers, frequency matters.  The higher the frequency, the lower the inductive losses and the higher the equipment one can use.  (This is why aircraft use 400hz power buses because they can use lighter transformers.)  Mains power in North America is 60hz, however the Pennsylvania Railroad employed a 100hz cab signal carrier frequency to eliminate the risk of cross talk from 60Hz mains.  This lead the PRR to actually adopt a 100Hz power supply in its electrified zone to eliminate the need for motor-generator frequency converters at every signal location.  Here we can see a retired 6.9 kv transformer on the former PRR Port Road branch.  You can see how the size compares with the 60hz transformers pictured above.

Here is a more contemporary example on Amtrak's NEC.

Today railroads are rapidly exiting from the utility business.  It's a classic case of outsourcing.  Now that public power utilities can be contracted to supply the power (even in rural locations), there is little reason for railroads to employ linemen and power engineers.  Let the power company power and the railroad rail. 

Monday, July 17, 2017

Come and 'C'

In the 1940's someone at the always cost conscious Pennsylvania Railroad wondered why if signals could be displayed in the cab, why was there any need to display them on physical wayside signals? Although not the first railroad to have such an idea, the PRR was the first to at least make such a concept ready for prime time. Implemented on the important-yet-not-that-important Conemaugh Line between Kitski and Conpit Junction, the PRR's main innovation was the 'C' Board or "Clear to Next Interlocking" signal, which allowed trains with failed or inoperative cab signals to proceed to the next fixed (and presumably absolute) signal, while still technically operating under signal indication and thus not needing to receive some sort of written movement authority. The assigned rule number, 280a, actually betrays the concept's roots in the old Manual Block System Rule 280, Clear Block, as opposed to Rule 281 Clear used in automatic signaled territory. Still numbered 280a under current NORAC signal rules, this can now be considered an Artifact Title since Rule 280 was long since removed. Both 280 and 280a can be lumped into the class of "super clear" indications, that can give trains 10 or even 20 miles of railroad at a shot.

Now I'd love to talk about how the technology behind Rule 280a works and how displaying 280a was implemented in towers, but both of those topics are the subject of ongoing research. Instead, today's post will focus on the 'C' signals themselves and how they evolved from the PRR's first deployment on the Conemaugh Line, through to the current flood of "Rule 562" territory on both Amtrak and Norfolk Southern.

The PRR's inaugural style of 'C' lamp was very much an ad hoc affair, making use of whatever materials were at hand. The the flashing lunar white marker lamps were provided by US&S PL-3 units, common to PRR position light signals, and they were surrounded by a rectangular piece of sheet metal with a white 'C' painted on it. The unit was attached to a standard PL mast by means of steel tubes that looked a lot like the type used to mount PL units to the central hub on PRR PL high signals. Here we see a surviving example of this type of 'C' lamp installed at CP-CONPIT.

Almost 50 years would pass until this method of operation once again gained traction. Metro North was looking to replace the New Haven vintage suspended semaphore signals, but the layout of the electrification system would either require completely new signal bridges or new suspended signals that would come with many of the same maintenance headaches. The solution was 562 operation that would allow most wayside signaling locations to be just removed from service. As 1980's Metro-North was still somewhat rooted in Conrail operating rules, it adopted the 'C' signal making use of PL-3 units surrounded by a pill shaped backing with a white 'C' painted above the lamp.

Conrail was next to pick up on the cab-signal-only crazy as a number of its cab signaled former PRR routes came up for re-signaling. The Morrisville Line, formerly the PRR Trenton Cutoff, made use of GRS SA searchlight heads modified to display a single lunar white light with a small reflective white 'C' on a flap of sheet metal mounted above. I am not sure if Conrail was recycling surplus SA heads made available in its transition to tri-light signals or if they were purchased new.

The next generation of Conrail "562" followed shortly thereafter with installations on the Fort Wayne Line and the east end of the Boston Line between Framingham and Worcester. These made use of more traditional railroad marker signal lamps, each mounted with a circular backing and the same metal 'C' flap as seen on the searchlights.

 Of course one must account for dwarf signals. In both the Safetran stack and searchlight configuration, Conrail would place an extra lunar white Safetrain cube signal to the right of the signal with the same reflectorized metal 'C' fmap. On the Morrisville Line, there was at least one instance of PRR PL dwarfs getting an attached 'C' lamp, but these were replaced a number of years ago.

Meanwhile, the MBTA was the next railroad to employ 'C' signals when it rebuilt its Old Colony Lines. Here the distinctive feature was the reduced size of the 'C' lamp target, looking a bit like one of those small round lollipops. Like with Metro-North, the 'C' was incorporated into the target, placed above the lamp, which itself was of the Safetran square modular variety. 


Fast forward to the 2000's and, like everything else signaling related, it appears that the venerable 'C' lamp has been standardized. Starting with Amtrak's 1999 Secaucas Junction and high density signaling project, Rule 280a has been displayed by a pair of Safetran modules, the lower one holding the flashing lunar white lamp, and the other one a reflective (or possible backlit) 'C'. This in turn is surrounded by a pill shaped backing, similar to the original Metro-North style. This layout has gone on from Amtrak to be employed by New Jersey Transit and Norfolk Southern.

The one exception is in the realm of dwarf signals where Amtrak's standard modular LED searchlight was modified to mount a lunar LED lamp next to the lower "head" of the dwarf stack and a blanked module with a white 'C' next to the upper "head" of the dwarf stack.  BTW, anyone wondering what a 'C' light looks like when displayed, here you go.

Will there be more varieties of the 'C' signal?  Possibly.  There are a lot of railroads with a lot of signaling systems that haven't yet done all in with the waysideless future.  What happens they are certainly more interesting than plan old Darth Vaders.