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Friday, January 18, 2013

BEGINNING DCC


Construction of my SP Cascade Line has progressed to the point where serious consideration must be given to the electrical arrangements for it.  Just as track, especially turnouts, is the critical foundation stone of any railroad (12 “ to the foot included), the electrical system becomes critical for a model railroad.  In my typical “analyze it to death—and beyond” mode, I’ve spent much of the past couple of months studying, planning and refining the electrical plan for the railroad.

Three major electrical systems stand out: the throttle system (how to control the locomotives), switch control, and the signal system.  All three must be provided for the SP Cascade Line.  Sound (good current practice) standard installations with good wiring practices (neat, labeled, easily swapped out) are essential to successful functioning and maintenance of this large project.  That principle drove me into the manuals and validation of my overall concept and hardware design over the past couple of months. 

The throttle system for the SP Cascade Line will be a North Coast Engineering (NCE) radio system.  This choice was made many years ago, but is only now beginning to be realized in hardware.  More on the initial hardware appears below.  A Digital Command Control (DCC) system would be needed as this layout is designed for operations.   The model railroad operating community has come to expect the features of independent locomotive control on the same track, provided by DCC.  The DCC decision was not as easy as it might appear, as I am faced with a lifetime accumulation of locomotives that will now need decoders installed.  Southern Pacific steam locomotives often use Vanderbilt tenders (cylindrical water tank), presenting additional challenges to decoder (and possibly sound speaker) placement.   The operating requirements of the railroad drove the choice.

The key feature that drove me to selecting NCE is their user-friendly interface with the throttle.  I spent a career designing cockpit interfaces to make a pilot’s job easier, so I am particularly sensitive to easily understood and performed control interfaces with hardware.  Guided by thoughts Joe Fugate posted on his Siskiyou Line website, I investigated and used each of the major systems, thereby validating thoughts Joe expressed.  Fortunately, I lived in the San Francisco Bay Area at the time and had access to most of these systems: NCE, Digitrax, Easy DCC, and Lenz.  While each system has at least one strong point, I found the total system design by NCE made the best choice for me and the intended operations on the dream railroad.  One of those operations involves the potential of adding and removing a point helper on a passenger train.  In practical DCC terms, this means making and breaking “consists” during an operating session, something made easier by NCE’s throttle design.

With the choice of system made, the hardware manifestation of that choice remained dormant until I moved into the dream house with the dream basement.  I purchased my NCE PowerCab prior to the move, but used it only for a little bit of locomotive checkout.  Sound in locomotives adds a new dimension to model railroading!  The PowerCab will be used mostly as the “programming throttle,” as it also has a good USB computer interface.  I did get my PowerCab upgraded with a radio board, so it can serve as an additional full-feature throttle on the layout.  (Thanks Mark S!)

PowerCab with independent programming track and Bowser-Stewart DRS-615 loco.

With track being laid, the need for the layout throttle plan became more real.  My preliminary plan featured three ten amp boosters feeding power districts via DCC Specialties PSX circuit breakers.  The idea behind the 10 amp capacity was to provide plenty of current reserve for recovery from electrical shorts in the presence of many sound-equipped locomotives.  As I moved closer to hardware purchase, I revisited this design choice and changed it to more conventional (for HO scale) 5 amp boosters.  The 5 amp boosters are better suited to the dispersed power needs of the SP Cascade Line track plan.

SP Cascade Line Throttle Power Booster Location Plan, January 2013

The current throttle booster plan was developed and passed on to my electronics brain trust for review.  The choices are mine, but I listened carefully to my advisors. 

A side note is appropriate about those advisors.  I was fortunate to fall into a weekly gathering of model railroaders in the South Bay Area—Silicon Valley—during the past half dozen or so years.  The “DCC Lunch” provided a forum for exploring many ideas related to model railroad electronics and operations.  Week after week, we met at the local Chili’s restaurant, gathering for good food, comradery, and often enlightening discussion.  I miss those guys, but such is the price of moving to a dream location and a dream home.  That Chili’s just closed.  I wish my former lunch mates good fortune in finding a suitable new venue.  The Santana Row Chili’s provided a wonderful venue and was part of the chemistry that made the DCC Lunch gathering click.

With my booster and power district plan developed and reviewed, it became time to purchase the initial building block—a DCC “starter system.”  Shown below is a test “installation” intended to test the functioning of the new PowerHouse Pro-Radio command station and booster.  It has been great fun putting into practice the theoretical knowledge gained over the years.   My former DCC Lunch-mates and others in the SF Bay Area may now smirk, laugh and wonder: “What took you so long?”

Test “installation” of NCE PowerHouse Pro-R with Athearn Genesis SP GP-9 locos and bay window caboose—with lights and loco sound.

Now that I have had fun playing with basic decoder settings, loco control and sound, it is time to complete some track laying, wire it and provide switch machines!


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