As promised, I took a spare R3/RSW an R7 a couple of receiver packs, my DX6 to use as a BuddyBox and a 3.5mm Mono audio cable and tested the use of an R3/RSW to create a wireless buddy box interface.
Step 1) Make a trainer cord with a JR connector on one end and a 3.5mm mono plug on the other to allow the DX6's trainer jack to be connected to the PPM Input of R3/RSW. I used an off the shelf Mono/Audio cable with a 3.5mm right angle connector. The shield of the cable gets connected to the negative pin of a JR style connector while the center conductor connects to the JR connector's signal pin.
Step 2) Download Receiver firmware V3.06 and the associated release notes from the Esprit web site (
http://file.espritmodel.com/firmware...Tx306_R3HW.exe ) and install the firmware on the R3/RSW. I've been told that firmware V3.06 downloaded from the Jeti upgrade site doesn't recognize an R3/RSW properly. I've only verified this setup using the firmware downloaded from link provided.
Step 3) In the DS16's model memory for the aircraft to be "buddy boxed" Select Advanced Properties, Wireless /Trainer menu.
(a) Select Teacher Mode, assign a trainer switch and "Pair primary tx module" to the receiver in the aircraft to be buddy boxed.
(b) Install a bind plug in the EXT port of the R3/RSW and connect the JR connector end of the trainer cord to port 1 (PPM Input) of the R3/RSW and the other end to the DX6's trainer jack. The DX6 needs fully charged batteries and must be powered Off when used as a buddy box.
(c) Connect a receiver battery to any free port of the R3/RSW and then select "Pair Secondary tx module" at the DS16.
NOTE: You MUST have the PPM input connected to the R3/RSW or it will not bind.
(d) Once pairing completes, remove bind plug from R3/RSW and power it off.
(e) In the trainer interface, assign the appropriate channels for Throttle, Aileron, Elevator and Rudder.
Step 4) With the Dx6 powered off, connect the trainer cable to the R3/RSW and plug it into the DX6 trainer jack.
With the DS16s trainer switch selected to give control to the student, the servos connected to the R3 should now follow the controls of the DX6.
These instructions were put together very quickly after testing the trainer interface so I may have made a couple of mistakes or not described things all that clearly so feel free to point out anything
the doesn't make sense or ask questions.
Based on the assumption that a head tracker looks just like a buddy box to the DS16, if you can get a wireless buddy box working, the head tracker should also work assuming the correct cable to connect it to the R3/RSW.
EDIT: I also posted this on RC Groups and one of the guys over there saw my post and decided to try connecting his FatShark headset and has verified that it works properly using an R3/RSW.