I purchased a 6EXA last year... upgrade from the skysport 4. I recenlty acquired a 120 sized plane that is designed for using 2 servos for the elevator, one for each half.

At the time I assumed that I could program the 6EXA to handle the setup... it seems innocuous enough. After a few days of strugglung though, I am appealing for help and suggestions!

Initially I had hoped to use flapperon mixing as well, but that is secondary to getting the elevators set up right. Currently I have both servos mounted, and mechanically they are as geometrically identical as I can manage (I can't see a visual difference in the servo/linkage geometry). Now all I need is to get both servos operating in tandem (with one servo reversed). The closest I have managed so far is to P-mix channel 2 (elevator) with channel 6 (flaps), and have 6 at -100% mix. The problem with this is twofold... firstly, the Flap knob is easy to bump, and will move one half of the elevator. The other problem is that the elevator digital trim adjusts only the other half of the elevator.

In my initial attempts I tried mixing chan 2 with chan 5 (freeing up channel 6 for the aileron/flapperon mix). Unfortunately, you only get half travel of the one elevator half, and it depends on the setting of the "gear" switch. Again, trim affects only one of the elevator halves.

Either I am missing something in the radio, or the functionality is not available through mixing.

Does Futaba have a recommended solution to my problem (It is not a unique issue, is it?)
So far I am aware of the following alternate solutions:
get a servo reversing circuit for one servo, and put both servos on channel 2 with a "Y" harness.
get a reversing "Y" harness.
get a "matchbox"
get a different radio.

I have read varying reports on the success of using servo reversers/reversing "Y" harnesses because they are not necessarily going to produce equal travel on the elevator halves. I am reluctant to go that route on this plane (which is my first attempt at IMAC....)
The matchbox is expensive.
A new radio is very expensive.

Is there something I am missing?

gus

Hi Gus,

Since the 6EXA is only a beginner's type computer, it does not have the functionability for what you are wanting.

If you are wanting to fly IMAC, I would recommend the 9C, it will have the mixing capabilities that you are wanting and will need for competition.

If you feel that the cost of doing this is too much, then the only alternative would be as you suggested, using a y-harness and a synchronizer for the trim adjustability on your elevator. When using a synchronizer you will be able to achieve full and equal travel of both servos.

I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.

Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician

Withdrawn.

Thanks for th input.

For what it's worth, I came up with a functional solution.... even if you don't like it... I reversed the Pot and motor on one of the servos, thus reversing the servo. It will go through some rigourous testing, but it looks really good so far.

Having spent more than my budget for the plane, I am not waiting months (well in to winter) to get the money needed to upgrade my radio. I am desperate to get it airborne.

gus

whats the pot position? anyway ill be investing ina Y harness reverser for about 18 bucks

Basically, I performed surgery on the servo. Cut and crossed two of the "legs" on the servo Potentiometer (the "pot", and reversed the plarity of the motor. You need a soldering iron, wire, wire cutters, and a steady hand (and a willingness to void your warantee).

gus

ahha just get a servo reverser!

just flip the servo arm. cost free.[X(]

well lets keep it simple fixing the servo to reverse itself is a hard fix and you must be very careful or lucky...
the simple fix is put one servo arm on the other side of the servo... wallah it now travels in the same direction
and no doctoring the servo...use a regular y cord to connect the servos to the receiver...doesn't cost much,
takes very little time...and mine flys great...tracks very straight through the air... equal up and down...
when you cut the holes for the servo cut one above the other at a distance to keep the servo arms
at the same throw when they move...imagine a straight line through the model and through the middle
of the servo arms... one arm faces down the other faces up...