An Introduction to Direct Radio Whereas I haven't seen much posted on Direct Radio and I've been grateful for those posting regarding their DCC systems, I'll try to share some of my humble experiences with Direct Radio/Railpro, hereafter referred to as DR or RP. Those familiar with DCC systems know that digital commands are sent to locomotives or accessories equipped with decoders via track power from the hand controller (HC, throttle), computer or phone via the command station. Somewhat like a computer network with locomotives and accessories having addresses. Traditional DC systems vary voltage to the tracks controlling engine speed. DCC maintains constant voltage and controls engine speed thru digital commands, by controlling the amount of time a locomotive "sees" track power via the decoder reading the digital commands. DR places a module in the locomotive or accessory that communicates in real time with the locomotive/accessory. Power is constant like DCC but a command station to encode the digital commands is not utilized. Because of this, to speed match you need only run a simple motor current load test (locomotive held stationary while the hand controller (HC) runs a quick test running the motor to 100% throttle and measuring the current load). This information is stored so that when you consist locomotives they talk to the HC in real time comparing the current load of each and adjusting each on the fly. Since digital commands are not sent via track power, using the track as a bus, you could run dead rail with an alternative power source, making it similar to RC planes/cars, making it popular with large scale modelers. Not a paid spokesman. ..