The ability of a variety Digitrax throttles to work together on layout equipped with a variety of wireless technologies is part of the beauty of LocoNet. With LocoNet, it is simple to add components to the system and have all of them work together.
Digitrax infrared throttles will operate on any layout equipped with UR90 infrared receivers, UR91 simplex receivers and/or UR92 duplex transceivers. All of these panels are equipped with infrared receivers. All current model Digitrax throttles have infrared emitters that will work wirelessly with any panel that has an infrared receiver.
All current Digitrax throttles can also be used a tethered throttles when plugged in to a Digitrax equipped layout.
Duplex Radio equipped throttles have part numbers ending in D for duplex. The DT402D & UT4D are duplex radio throttles. They are also equipped with infrared emitters. This means that they will work in duplex mode with the UR92 duplex transceiver, in infrared mode with UR92, UR91 or UR90, or as a tethered throttle when plugged in to the layout.
Simplex Radio equipped throttles have part nubmers ending in R for radio. The DT402R & UT4R are simplex radio throttles. They are also equipped with infrared emitters. This means that they will work in simplex radio mode with the UR91 simplex receiver, in infrared mode with UR92, UR91 or UR90, or as a tethered throttle when plugged in to the layout.
The Duplex radio UR92 transceiver operates at 2.4 GHz. It will not work with R throttles. The UR92 cannot be converted to a UR91.
The Simplex radio UR91 receiver operates at 916.5 MHz. It requires a UR91 (916.5 MHz) receiver. It will not work with D throttles. The UR91 cannot be converted to a UR92.
You can't use an "R" throttle in simplex mode with a UR92, nor a "D" throttle in duplex mode with a UR91 (except on IR or as a tethered throttle plugged in) because they are different frequencies.
You CAN use both types of throttles on the same layout if you have BOTH a UR91 and a UR92 installed.
UT4, DT400, DT402 are all tethered or IR. They can communicate using Infrared with a UR90, UR91 or UR92.
UT4R, DT400R, DT402R are all simplex radio, infrared or tethered throttles. These will operate with UR91 in simplex mode or a UR90 in infrared mode.
UT4D, DT400D, DT402D are all duplex radio, infrared or tethered throttles. Duplex radio operation requires a UR92 (2.4 GHz) transceiver.