Using the NCE D13DRJ Wireless Decoder with the ProMiniAir Transmitter

Introduction

The NCE D13DRJ, now, sadly, discontinued, is a dead-rail DCC decoder that originally touted compatibility with the Stanton Cab. You can find the decoder’s documentation here. The following is a description from NCE’s website (some of the information may not be accurate):

Dimensions: 1.30 x 0.640 x .285 inches – 33 x 17 x 7.5mm

Direct Radio Wireless DCC decoder operating at 916.50 MHZ [916.48MHz]

Features of this decoder: Built-in radio compatible with the S-Cab by Stanton Wireless, Equipped with NMRA 9 pin DCC ‘Quick Plug’ Torque Compensation for ultra smooth low-speed performance. Motor rating 1.3 Amp continuous, 2 Amp peak (stall). All four function outputs have lighting effects generators. Select from 15 different lighting effects. Full support for LED lighting.

The D13DRJ is designed to be used with Stanton Wireless A.K.A. S-Cab since he uses the exact same wireless chip and frequency we use 916.50 [916.48MHz] MHZ. Tam Valley claimed that even though the receiver they use is 916.37, it would work fine. We had to find someone with a CVP T5000 for compatibility testing. Originally we relied on CVP’s claim of compatibility but have found that it is not true. [This statement is not entirely correct. See comments below.] We have changed our website and documentation to reflect this.

Examination of the NCE D13DRJ revealed it uses the same receiver chip (the Linx RXM-916-ES operating at 916.48MHz) as the older Tam Valley Depot Mk III receiver, which I previously verified works with the ProMiniAir transmitter (PMA Tx) on Airwire Channel 16 (916.37MHz). So, I was optimistic that this decoder would work the PMA Tx.

NCE D13DRJ with Linx RMX-916-ES transceiver operating at 916.48MHz

Using the ProMiniAir Transmitter to Control the NCE D13DRJ

The photo below shows the PMA Tx connected to a Digitrax DCS52 controlling locomotive #4291. I set the PMA Tx to transmit on Channel 16 by placing the DCS52 in ops mode at address 9900 and then changing CV255 to 16. After exiting ops mode, I set the loco address back to 4291. 

The ProMiniAir transmitter connected to the Digitrax DCS52 set at DCC address 4291

Simultaneously, the Digitrax LNWI, connected to the Digitrax DCS52 via Loconet, receives commands from the iPhone WiThrottle app controlling locomotive #3 (the default address for the NCE D13DRJ).

The PMA transmitter is sending commands to the DCS D13DRJ on DCC address 3

Below is a demonstration that the NCE D13DRJ receives commands from the PMA Tx using DCC commands from the iPhone’s WiThrottle. While it’s difficult to discern the motor’s turning, the accelerations/decelerations when changing direction is easy to observe.

The iPhone WiThrottle app sends DCC commands to the Digitrax DCS52, which in turn transmits DCC commands to the DCS D13DRJ via the ProMiniAir transmitter on Airwire Channel 16

Conclusion

The PMA Tx is demonstrably capable of controlling the NCE D13DRJ. While NCE has discontinued the manufacture of this decoder, it is frequently available on eBay and is an excellent dead-rail decoder option for smaller scales.

PostScript: A Note about Airwire Compatibility

The CVP Airwire T5000 transmitter (and presumably all other CVP Airwire transmitters) partially works with the NCE D13DRJ on Airwire Channel 16: speed and direction control work reliably, but the function keys do not operate consistently. The cause for this behavior is unknown; I have never encountered this kind of incompatibility before.