Ultimate7e tutorial: Processor upgrade

See few posts back, link was posted but it is out of stock. The better antenna would be the from AN007, as it is stub matched. They call it inverted F antenna, instead of J-Pole.

I fully agree with you PB, I personally would recommende some 100pF capicitors etc close to CPU I/O, for switches pots, to ensure RF is shorted. For high speed lines , possible need RF choke few turns etc. But basically the antenna in or out would not make much difference, as the plastic does not shield anyway. So Outside antenna also cause fieldstrength inside, so do other transmitters like uhf, fm,radio, close cell phones etc etc...Unless the housing was metal sheild and antenna outside, then would agree.

Fully agree the antenna has to be Free from metal around, indeed this is a bit of trade off, in my case you can see that the rear part of pcb antenna is gound plane, this is pointing to inside of transmitter. The radiating hot part, only has only plastic view.

But you are right antenna's radiating element are officially to close to each other antenna, and bit to close to the metal switches.
But it is not that bad and the best what can be achieved in the devo 7e

i remember reading when using a pcb antenna to not have a ground plane behind the antenna element on the opposite side of the pcb?

One more successful upgraded U7E report from China 5iMX forum
bbs.5imx.com/forum.php?mod=viewthread&ti...14739&extra=page%3D1
He changed MCU with 2 solder irons.

21!!! (I'm counting happyharry's inbound board ahead of time )

I've upgraded my 7E processor to a STM32F103RET6 & new batch 4in1 module, I use gas soldering iron to remove old MCU.

22! Great! Looks like more of those 4in1s are surfacing also. Let us know how it performs!

Leo Li wrote: I've upgraded my 7E processor to a STM32F103RET6 & new batch 4in1 module, I use gas soldering iron to remove old MCU.

Hi Leo Li,
Great soldering skill.
Would you please check your 4in1 module for me? how many pins/pots on the left side of module? 12 or 13 ?
Thank you very much.

13, taobao seller told me it should be latest version

Leo Li wrote: I've upgraded my 7E processor to a STM32F103RET6 & new batch 4in1 module, I use gas soldering iron to remove old MCU.

welcome to the brotherhood

Leo Li wrote: 13, taobao seller told me it should be latest version

yes that's the same as mine, and after testing i've found that all of the issues with the earlier version 4in1 boards have been corrected

Leo Li wrote: 13, taobao seller told me it should be latest version

That's correct , if you got 13 pins version board , there is no overheating / LNA connection problem, all those issues had been fixed.

2 Devo 7E and 3 processors later...I am joining the 256k club

welcome to the brotherhood

so you have 2 u7e's? that takes us to 24 known u7e's

What I meant was , I broke the first one. Ordered a 2nd one and almost broke it too. Destroyed 2 CPUs and on the third tries, I got one U7E.

I did not have a hot air rework station and I destroyed the PCB pads on the first 7E. So out to Amazon and ordered one.
the 2nd 7E, I tried again but could not see so I went out and bought a inspection microscope.
One more thing, another new 7E is on the way because I thought I was not able to fix the 2nd 7E.
This hobby is getting expensive.

yeah i had some issues with my first one too, but at least we both got there in the end

so we have 23 known u7e's

for anyone else considering this swap without an air gun for removing the original mcu i thoroughly recommend using something like chip quik, it's a low melting temperature solder and makes removing smd chips much easier with a normal iron, plus you are much less at risk of lifting pads/traces due to too much heat

Woohoo 23!

This hobby does indeed get expensive. Glad to see your wallet survived and your perseverance paid off! You gonna upgrade the inbound 7e?

HappyHarry's right about the chipquik, I've used it before and it is easier. It is a bit on the expensive side but cheaper than buying a new 7e...

You bet !!! i will. I need to get a new processor for it. Now I know what to do , I hope no sweat now

This is the problem. Wife already asking why some many controllers in the room ?

i got
2 Turnigy 9XR with a lot of modules.
1 Turnigy 9X
1 Devo 10
3 Devo 7E - ( 1 coming and 1 broken )
1 Devo 12S
1 DJI P3

I am eyeing Devo F7 or Devo F12E

FDR wrote: Well, I can understand her...

+1 lol