OK - Sorry for the delay - Yes, you can bind to both of these receivers to the XJT, but you can not bind to them both at the same time. The V8R4-2 will bind in D8 mode, and the receiver has to be in emulation mode via a jumper. (Check the instructions for the receiver as I do not recall the position for the jumper.) For the RX6R, you will bind in D16 mode. This is pretty straight forward process, but there are some things that can cause trouble.
Here is my binding method that I think is better than the method Frsky documents.
1- Start with the receiver. Power it up like normal and notice what the LEDs do. Now turn off the power, bush the bind button and turn the power back on while holding the button. Once power is on, release the button. The LEDS should have a different little dance. This indicates it is in binding mode. If the LEDs are not doing a different dance, then power off and try again. Don't be surprised if you have to hold the button down for a little bit after you turn on the power. Just watch the LEDs.
2- Go to the transmitter and with the correct model memory active, set your model number and then set the radio to D16 mode, and finally click on the bind option and answer the questions the system asks you. (Typically will want channels 1-8 and telemetry on.) As you hit the final OK, wtach the LEDs on the receiver. You should see the little dance change a bit as the transmitter and receiver complete their bind. You can now turn off the power to the receiver and cycle it back on, and on the transmitter, just hit enter. You should be fully bound and have yet a different little LED dance on the receiver.
What to do if you can't get the happy LED dance at the receiver? Try again! I have on occasion had to repeat this process 5 times. I once thought I had a DOA receiver, but it eventually took the bind and has been fine ever since. FrSky does test them all before they approved to ship out. DOA is very rare.
Ok - So still can't get a bind? Well in the old days I would tell you to contact us, but now we have to ask ourselves if we have attempted any firmware upgrades on the ACCST for the the transmitter or receiver. If you have down a firmware upgrade on the receiver, or you bought it from overseas, chances are it has the wrong version of firmware on it to talk with your radio. Here is a simple graphic we made up to help folks understand a little more about the firmwares:
A lot of folks get the RF firmware mixed up with OpenTX. They are totally separate items. The RF firmwares MUST match on the transmitter and receiver for them to bind.
Hope this helps.