Yes, go into frame rate and select 5.5ms (16.5ms isn't even an option on my radio here) and then go to bind. Hit bind and it shows 16.5ms once the binding process is done.

I've tried it with just the ESC plugged into the receiver and with the servo and PT plugged in. Same results both ways.

just purchased a super nice used dx4r pro for my son, i have one myslef and it binds to the older recievers, i tried the one i bought and it wont bind, same firmware i believe, any ideas? mine works with the older recievers

The most recent firmware update disabled support for older receivers. The one you have bought might have been upgraded to that version.

As I have discovered this is my issue as well. Per Spektrum, the latest firmware for the DX4R PRO makes it so the radio cannot bind with original DSM receivers and can only bind at the 16.5ms frame rate with DSM2 receivers. Doesn't make sense to me why, but it is what it is. I now have to find a new home for my SR3520 and buy an SR2000 or its' new replacement if I want that ultra fast 5.5ms frame rate.

From Spektrum:
"This version will disable all RF protocols except DSMR and DSM2-16.5ms"

This is why I am not upgrading the firmware.

Just picked up 2 dx4r pro's for my son and I. Had I not read this, I would have updated them. Thanks! Any other reasons for the update?

Dx4r problem
 

Hey guys i have a spektrum dx4r transmitter and the little orange led light on the aerial doesnt go on anymore. What does this mean? I have tried binding it to a couple of my receivers aswell as just turning the controller on and still nothing.

The 4R won't bind with some receivers like older DSM receivers. It should work with receivers marked ,DSM2 or DSMR.

So what about the orange light on the aerial? Does this matter if it is on or off?

I just checked and mine comes on within a second of the power up. Right when it says Spektrun in start up. Id give Horizon a call to see if they can help. Of course make sure youve done the easy stuff first like changing batts, etc..

The best batteries to use in thus or any other transmitter are the Panasonic eneloops. Not the pro ones but the regular white ones. They rate much better than the pros. These are what all the pro photographers use in their flashes. There has been extensive testing on batteries to determine the best ones and the standard eneloops come out on top. They hold charge the longest, recycle the fastest, and can be recharged the most number of times. Real good prices on amazon with the great charger that comes with them. If you look into it these batteries are real impressive.camera flashes are high draw devices and their recycle time is directly related to the quality and type of battery you use.that is how I found out about them.

Anyone try a different wheel on this radio? Looking for options. tia.

I am running UltraCell 2800MAH NIMZ cells in mine, 1.6v per cell. works awesome and lasts forever!!

The update apparently enables telemetry support for the SR4000T and SR6000T, so if you do not need that there is apparently no reason to upgrade the firmware.

NIZN batteries are the way to go, nothing is even close. You have to use a NIZN charger for them. I have seen 4 batteries and charger for less than $20. I also have a spare set of 4 when needed. I put a lipo in my DX3S and it is still showing 7.9 volts 3 months later. That is very impressive and the battery cost like $12. I had to mod the radio and the battery. Soldering a Deans connector onto a battery makes me every nervous to say the least, I took lots of time doing it.