DX6i Proportional Flaps

[mike_cj0]

Hi all!

Ever since i got my DX6i i have wished it had come with proportional flaps rather than the on off switch.

I have been doing a lot of reading about the insides of the DX6i and it doesn't look like its a straightforward modification to make. It would have been so nice if we could just swap the switch for a pot!

I've not opened my DX6i yet as I'm not sure what effect it has on its warranty but that runs out soon so i will soon be able to have a play. I guess this is really just a thought experiment at the moment but it might help other people who would like to achieve the same thing.

From what i have read it looks like the DX6i uses a digital input on its processor for the flaps and gear switches rather than the analogue inputs for the other 4 channels.

So i started to think about how it could be altered.

I've come up with two ideas.

The first would be to add something like a pic chip in the transmitter that would read in the value of a pot and output a series of pulses depending on that value to the flap pin on the transmitter and then at the receiver end have another one to decode and control a servo.

This is something that i could do with my current knowledge/skill set and it would be pretty easy to do. The big problem would be the added weight from the pic chip at the receiver end.

The other option would be to interface something between the transmitter processor and the rf stage that would modify the flap portion of the packets according to the value of a pot. Assuming that the receiver has 6 proportional outputs and the current on/off limitation is only at the transmitter stage then this would be the best option as no extra electronics would be needed in the plane. The only problem i have with this i that i currently don't have the know how to do such a thing. :o

What do all you electronic geniuses think?

Mike

[David T]

If the Tx flap input is digital it will only convert inputs to 1's and 0's. If by option 1 you intend feeding a 'code' through it would have to be synchronised with the frame length (nominally 20ms), ie: a 1 or a 0 every 20ms which the Pic on the receiver end accumulates enough of to convert into a proportional 1 to 2ms servo pulse. I think you would have to pick up the frame length from the communications between the MCU and RF board.

If you can do the above, then it's not that much more to make a Pic intercept 16 bytes to the RF board and replace two with your own. However, signal integrity is riskier and latency higher.
David.

[zwever39]

Hi,
On my DX7 I use the throttle for flaps (no motor) and use the program function to slave aux1 for the other flap. No Y-cable needed. Possibly that would work with the 6i also.