The Controller Part 1

A project log for DJI FPV Investigations

Things I've learned about the DJI FPV quadcopter.

Duane DegnDuane Degn 03/21/2021 at 20:150 Comments

I initially thought the controller was going to be really hard to open but I was pleasantly surprised to find four Philips screws at the bottom of holes under the back rubber grips. The red circles in the photo below show the location of these four screws.

I was able to pry the shell open but starting where the rubber stick holders are sandwiched between the two halves. It wasn't easy to pry the controller open but it wasn't much worse than many game controllers.

I took about the button and the potentiometer located in the top shell.

The camera angle control dial has a cool return to center gizmo.

I took mine apart so you don't have to. It's a bit of a trick to reassemble.  I've seen other return to center pots before but I think this mechanism is more involved than other gadgets I've taken apart.  The yellow shape near the center is a plastic tab which is likely used to make assembly easier and faster. 

The lower section of the remote has a lot more going on inside.

There are two 18650 Li-Ion cells inside. These cell each have a thermistor to monitor their temperature. I haven't figured out if the cells are in series or if they're parallel yet. My guess is they're wired in series.

After removing the batteries, I removed the bottom heatsink. A good portion of the weight of this controller is from the heatsinks. There's a round cutout in the heatsink to allow the buzzer to pass through it.

Above are the plastic buttons and the two leaf springs used to hold the vertical axes of the joysticks. 
Above is the flat flex cable with connects the two main boards of the controller. The cable plugs into connectors seen just right of center in the photo below. The battery connection causes this cable to bend away from the PCBs. The bent cable can be seen next to the black heatsink in some of the earlier photos.

The two main PCBs rest on the black heatsink above. The back of the top heatsink can be seen still in the shell in the photo above. The top heatsink has been removed from the shell in the photo below.

Above is the PBC which has the USB connection, two buttons, and the power LEDs.Based on the wires, it's pretty clear this controller has two antennas. I was surprised to see the shape of these antenna.

There's a wide 15mm x 30mm antenna in the base of the antenna and an 8mm x 30mm in the left side of the antenna. The right side of the antenna housing is empty.

The backside of the unconnected PCBs have two traces. The traces are about 22mm long on both the PCBs but the traces on the narrow PCB are slightly farther apart than the traces on the wider PCB.  The traces are 6.8mm apart on the narrow PCB and 5.8mm apart on the wider PCB.

The plastic spacer holds the unconnected PCBs 5mm from the wired PCBs.

To be continued.