Friday, 20 May 2016

CX-10W drone repair

At the time of writing, I am still waiting for the arrival of the replacement CX-10W from Banggood. So let's see if the burned out drone can be repaired. The charger is pretty much gone, but as the CX-10C uses the same one, I can use that.

Remove the props

Note the position of the propellers. If the quad flips or does not take off after reassembly, you probably have installed them in the wrong order.

Open the craft

That is not as easy as it sounds. The phillips screws are easy enough to remove.But the brackets were harder to unlatch than I thought.
I found it easiest to wedge a fingernail between the PCB and the top shell and unhook the plastic bracket with a spudger.

Locate the fault

I had noticed the green enamelled wires protruding from under the top cover. 
It was most likley to be at least part of the problem.

What looked like a bundle of green wires, really is only one connection connecting the two boards. Obviously that bundle had made contact with the power switch's metal case. This is soldered to the PCB's ground plane.

Quick fix

The cleaner solution would have been to fix the wire's insulation with some kind of varnish. But I didn't have that within arm's reach. What I had instead was a roll of Kapton tape. (Or a cheap knockoff) to insulate the switch's housing against the green wire.

Reassemble

I aligned the wires carefully and fitted the camera back into it's place. It all fits tighlty into the the shell, so some care has to be taken to arrange things properly.
Don't tighten the screws too much. The plastic wears out quickly.

Controlled recharge

To see if it charges normally, I inserted my USB-Meter. Everything looked normal, for what is regarded as "normal" with a charger basically consisting of a 2.2 Ohms resistor.

I always charge from one of my Xiaomi power banks. They switch off when the current drops. This adds a bit of safety to the otherwise unregulated charge process.


Test flight

Well... It does fly. But I don't like the handling/control. A touchscreen might not be the best way to control a drone, or it needs a lot of practice. I have flown quite a few drones but find this one particularly hard to handle.

The recordings are not too great either, but I'll do a bit more research on that.