Ultimate Devo F12E (devof12e-XMS) builds

The used solder is ROHS conform, no lead used. This makes it harder to solder.

Depending on your Tools, the easiest way is to put a lot of new solder on one side of the chips legs, so it touches every single leg on this side. If not all pins are covered you can "wipe" in slow manner over the legs so they warm up even. Then apply some lifting force from the pinless side of the chip and gently! try to lift the heated pins up a bit. The still cold pins on the other chip side will thus bend a little. When you have one side of the legs lifted a little bit it is easy to remove the solder from this side by using solderwick or a desoldering pump or even by the solderingiron alone, always heating the solder, take some away, clean the tip of the iron and again take some solder away until there are no connections to the solderpads.

The other side of the chip goes the same way, but it should get loose pretty fast as it is no longer held in place by the now already loose pinrow on the other chipside.

This way you already apply fresh solder to the pads.

When the chip is removed, go over the solderpads just to get them as "flat" as possible. This helps when installing the new chip.


Pre-tin the legs of the new chip.
Because of the wider new chip body, gently bend its legs closer to its body, check if you bent them enough by placing it over the solderpads. It will be raised a little bit from the mainboard. You could cut the extra length of the pins or leave them as they are. I left them as they are and after installation put some hotglue under the chip to support it a bit. But unless you have the manner to throw your tranmitter on the ground on a regular basis this should not be neccessary as the chip is very lightweight an the soldered pins support it very well.

When the pins fit good, place the new chip on the pads and secure it temporarily with e.g. some tape (you can hold it also in place with some tweezers, if you got a steady hand which I have not...). Now solder one leg of the chip and check if it is still aligned.
If it is ok, solder one pin on the other side of the chip, apply gentle force on top of the chip, the leg should "dip" into the tin on the solderpad.
Once again check the alignment.
If it is OK, solder all the pins to the mainboard by just touching the pin and pad, the applied solder is enough to create the connection in most cases.
Check for solderbridges, if there are some, just heat the spot with the cleaned tip of the iron, normally the solder should find its way to the correct place without bridges.

Good luck!

P.S. If you haven't plans to return back to Walkera firmware and not sure that you can desolder flash memory chip, you can cut chip pins by cutter one by one and then desolder pin remainders one by one. It is much more safe for PCB.