QX7 will not bind

[Marthr]

I have some X4R-SB units which are flashed with EU/LBT firmware : X4R_LBT_build151118.frk

Out of the box with stock firmware my new QX7 would not bind with these receivers.

My Taranis Plus (which is using XJT internal module firmware : XJT_LBT_build151223.frk) binds flawlessly

So I have flashed my QX7 XJT module with the same firmware (XJT_LBT_build151223.frk) and it still refuses to bind.

I am using these settings on both transmitters
Mode D16
Ch. Range CH1-16

I am aware of problems having the transmitter to close to the receiver, and this is not the problem as I have it a couple of metres away when binding.

Any ideas please, what can cause this ?

[Marthr]

I note that when the unit is powered on, although the RF board 3.3v test point measures 3.3v, the 5v test point on the same board only shows 2.7v.

Can anyone confirm that I should be seeing 5v here (relative to the 0v test point next to it).

If so, can anyone who may have access to schematic or circuit diagram, suggest why this may be happening, or which part of the unit might be at fault ?

Thanks

[Marthr]

As a follow up to this, I reflashed what I believe is the stock EU XJT for the Q X7, which I downloaded from
https://blog.seidel-philipp.de/frsky-ta ... n-eustock/

The firmware I put on was the 14/12/2016 one, file named STOCK_XJT_EU_build161214.frk.

It now binds fine.