I honestly don;t understand allt eh confusion - it's REALLY bad on the Digitrax Yahoo group. They lay it out pretty plainly on the Digitrax site.
DT402 - wired or IR, 29 functions (F0-F28)
DT402R - simplex wireless or IR or plug in (short pigtail), 29 functions, works with UR91 simplex radio receiver, must be plugged in to aquire locos
DT402D - duplex wireless or IR or plug in (short pigtail), 29 functions, duplex radio with UR92. Does not need to be plugged in for anything
If you currently have a DT400 (13 function, wired or IR) you can upgrade it to a DT402, 402R, or 402D
If you currently have a DT400R (13 function, simplex wireless), you can upgrade it to a DT402R or a DT402D. If you upgrade to the DT402D you will need to buy a UR92 to use the wireless.
DT40xR does NOT work with the UR92, DT402D does NOT work with the UR91. You can however have a UR91 AND a UR92 on the same layout int he same room to support both kinds of throttles - they use completely different frequencies.
Production of DT400 throttles has stopped, they are only making DT402's now.
Modeling the Reading Railroad in the 1950's
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