The Power of DCC
Years ago my dad and I built an HO train layout that operated through a variable-DC power supply, commonly called a “power pack” that created variable DC voltage on the rails from zero volts DC to 16 volts DC, and could reverse the polarity of the voltage, which allowed a train to run in the opposite direction.
The upper limit of the voltage for HO DC trains has a limit of 16 Volts. However, that’s only approximate. Some power packs will put out considerably more, and dirty track can make the effective power at the train considerably less without affecting train operation.
DCC (Digital Command Control) used on my layout takes the basic DC system and extends it by placing a “decoder” in each locomotive to provide DC to the motor, and by putting an alternating current encoded with control information on the track itself. This allows more than one train to run at the same time, as well as allowing for constantly-lit locomotive lighting (both interior lights, and headlights) and smoother control over low-speed operation.
This is a peek at how I operate the trains on my HO switching layout. What your seeing here is the "NCE Power CAB" that controls the locomotive in use at the moment through DCC, As seen on the screen unit 8117 is being controlled through various commands being sent from the power cab shown in my hand. Seen on the Power Cab display is the locomotive number (8117), that it is in forward drive (FWD), and several options (1-3) in play. The fast clock is indicating a time of 5:38AM.
The Power Cab depending on the type of decoder mounted in the locomotive, is capable of 28 different commands that include in the case of locomotive 8117, control of headlights, bell, horn, curve squeal, throttle, slow doppler horn, ditch lights, dim the headlights, startup/mute/shutdown, class lights, turn on number boards, cab light, brakeSet/Release, sarco valve slow (stutter), sarco valve fast (stutter), Sarco after shutdown, radio chatter between the engineer and trainmaster.
There are other settings that are also adjustable including individual volume control for all functions.
The Power Cab is capable of storing 6 different locomotives in memory, and in the case of my layout, I have 3 operational DCC locomotives, 2 that may be in standby on a siding, although being DCC locomotives, they will be heard idling the engine sounds coming from the speaker mounted under the hood.
If I wish to operate one of the other locomotives, I press the button on the Power Cab "Select Loco" , then enter the unit number for the locomotive that I will operate. Unit 8117 will now stand down, ignoring the commands sent to the newly selected locomotive seen listed on the screen. Its that simple.