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Old Dec 30, 2012, 03:49 AM
X10an1 is offline
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Joined Dec 2012
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I fixed it!

Originally Posted by andyj007 View Post
Well traded up my 6ex 2.4g to a futaba 7c 2.4.
Got the planes all programmed in no problems..
Basically i get to the calibration page and its like going crazy like the sticks are going mad...

Anyone else heard of this problem with Futaba 7c? im thinking of returning it to get my old 6EX back...

Any help apreciated..


I had the same problem. Used an Hong Kong sim-dongle and all the bars was going up and down like crazy, with only "some" interaction with my actual stick-input.

Without checking it out on an oscilloscope and just try to make a quick fix, I just soldered a capacitor between two solderingpads inside the transmitter.
I tried some different things to isolate the problem, and after I noticed it got better when I touched some solderpoints on the backside of the connectorboard I got an Impression that the problem really is related to exessive noise on the outputsignal. Maby because of poor current flow or bad impedance matching in the sim-dongle end and in the transmitter.. But like I said, I was not too busy trying to isolate the problem, I just wanted it fixed ASAP.

Of course I also searched the internet and found this thread. After I fixed it I just wanted som more guys to learn from my experience.


Well, it`s a rather easy fix. I just soldered a more or less random capacitor I had laying around to two solderpads on the backside of the circuitbord that holds the square-plug. The capacitor is a NON-ELECTROLYTIC, "relatively" small type. The one I used is 100nF 250V, but it is a rather random pick. The voltage rating is not important because all non electrolythic capacitors will tolerate this voltage-levels. I suspect I would get similar results even with a normal passive resistor of around 1-10k ohm.
OK, I must mention that I have an electronic degree, so by "random pick" I do not really mean completely random :-) but a capacitor value of 10 nF to 500nF was what I was loocking for.

Now I would really want to upload a picture, but I do not know how to do this. If it turns out I need mor than XX posts to post a picture, I will be mad at this forum and you will have to figure it out youself. But i will tell you that one of the solderpads is the signal line of the PPM signal, the other is only important to some degree. Tru something that seems like earth (0V) :-)
If you see a picture, I obviously figured it out :-)
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Last edited by X10an1; Dec 30, 2012 at 12:37 PM.
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