Who all is shunning DCC and staying Analog control?


When I was in the Air Force, my roommate and I designed and built a 'DCC' system, 1973. No computers, just discrete DTL circuits, one rail 0V the other 12V, but capable of digital pulses. I don't remember all the details, but it only used 16 bits, the first one being the 'MASTER SYNC' on both rails. 8 of the pulses were the speed control, so only eight steps, through an op-amp to the motor.
That sounds a lot like some of the early command control systems such as CTC-16, which became one of the first "standards" for command control when it was published as a DIY in the 1979 Model Railroader magazine. The issue with all those earlier systems that had a base voltage with an additional "signal" pulses over the top, was that the signal could easily get lost in the noise of the base voltage. It was often hard to tell if the problem was a real problem or if the signal was just not punching through the base power. The magic of DCC is that the power IS the signal, so one knows if the unit is getting power it is also getting the signal.
 
True, that. 21st century electronics would easily support some signal-over-power system that would overcome the weaknesses of CTC-16 for example. I think wireless would even not be too difficult. But that was not the case at the time when DCC was introduced in the 1990's. No doubt the simplicity of the approach was an enabler - at the time there was some skepticism about the "crudeness" of it, but nobody could doubt that it "just works". Perhaps in the distant future there will be some control technology that will supercede DCC and improve on some things like bandwidth (signal speed/capacity) and support bidirectional communications better (adding new functions to the programming on the main for example). Right now, I think we're in a situation of "if it ain't broke, don't fix it". Depending on your needs, that could apply to DC as well.
 
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