matada34

I will start be apologising as there is so many threads out there concerning 2.4ghz and similar stuff! I havnt found this issue before so I will write a new thread and hope I get some response, thanks for looking!

I have flown for years using 35mhz Futaba radio, Ive had the usual glitches and unexpected crashes which seem to be due to radio gear but overall I was happy with my FF9 and various RX's.
I am teaching a friend to fly and the obvious answer was to go for 2.4ghz, after weeks of research we decided to go for Spektrum DX6i. This was much to peoples reccomendations, I wanted him to have Futaba, but hey ho! So he bought a DX6i, AR 6200 and a 6100e.

We fitted his DX6i and 6100e into a small foam v tail model which could take a bit of a beating if he tried flying it himself and he could fly in a small garden, it was the flyingwings.co.uk mini V. This has a small brushless motor in a pusher configuration with 2 mini servos in each side of the fuz connected to the v tail. The plane flew great and the radio also worked a treat, at one point he lost the model out of site and somehow I managed to spot it miles away and get it back. The range also seemed A1 and we had several good flights over a month or so, I also have the same model but flew it on 35mhz. So... after weeks of uncertainty I sold my FF9 and bought a DX7 combo setup and the 6110e RX.

I setup the dx7 tx with the 6110e rx and headed down to the field where we had always flown, I flew the model for 4-5 mins and trimmed it out, all was fine. In the mean time my friend with the same model and the DX6i arrived so I landed so I could help get him airbourne. When I landed I made one alteration to my plane which was adjusting the end point adjustment with the DX7 TX settings. I turned the tx off and disconnected the battery in the plane.

I then turned my friends DX6i on and connected the plane battery, the left hand sevo immediately moved just over 45 degrees with no tx input. I moved the sticks and also something had changed with the V tail mix. So, hhmmm, scratched my head and had no answer to this issue... previously a week before we had flown and landed this model all fine.
After this I switched his kit off and decided I would fly mine again, so I went back to the DX7 & switched on, also connecting the lipo in the plane, beyond my belief exactly the same happened to mine, bearing in mind I had flown 5 mins before and landed with no issues.

So, I went home and did a bit of fiddling, I found the servo reverse had changed and also the servo centre position had changed. To fix this I adjusted the servo horn so it was vertical again and re programmed the TX so all was moving as desired. I then went back to a different field over the road.
I flew the plane for 20 mins with no issues, the bec cut in so i landed the plane. When I got to the plane there seemed to be no response from the servos, so off i went home.... I reconnected the battery and the servos worked but again the mix had changed and the same servo had gone another 45 degrees out. I then plugged in my spare AR7000rx and the same happened.

I then spoke to a guy named Perry at Horizon UK who was most concerned and bewildered by the fault. I sent all my spektrum kit too him for investigation. 2 weeks later we spoke and it was returned with no fault found! He had turned things on and off and done all he could but no fault was found.

I feel very uncertain using this Spektrum kit now, luckily my issues have been ground based but do I trust Spektrum? I do not know.... I spent over £300 on what I thought was top RC gear and already ive had to pay £15 returning it, is this good?! I think not, specially when it should be top class kit.

Has anyone else had anything similar happen or any ideas?

Thanks for reading and I will hope for some feedback.

PS - I have since not used the DX6i (or DX7), nore was the DX6i sent back to Horizon.

Campgems

I'm not familiar with the DX series, but I think some of them use a binding plug. Is it possible the plug wasn removed after binding and the RX's are latching onto the first TX they find?? This is indeed strange. Please keep the thread going to resolution. I'm sure it going to interest quite a few flyers.

Don

matada34

Hi, yes there are binding plugs which are used. There were definately no binding plugs connected to the rx's.

Thanks Matt

C130 Load

Sounds to me that the rx became un-bound to the tx.
Also the proper sequence is to turn on the tx then connect the battery.
When turning things off the battery must be dis-connected first then turn off the tx otherwise the rx might lose it settings and will have to be rebound.

This could be the reason you are having the problems you describe.

matada34

hhmm, ok... I will take this on board and make sure i do follow the seqence (im usually do this anyway) As for the binding, the rx's and tx's - they were still bound after the fault. When I reprogrammed the tx I did not have to bind the rx-tx again.

Thanks for you help, its all very interesting to see other points of view. Thanks Matt

V2PLUS10

A good rule to follow is to ALWAYS RE-BIND after any transmitter programming changes, servo directional changes etc. etc. Think of rebinding after changes as finalizing the deal....an extension on the rx bind port can help this procedure. I've not had the problems you describe, I hope you get them sorted and learn to trust your radio....Please keep us informed.....

Randy

Another thought is that you inhibit the flap switch, if you are not using the flap function. I try to inhibit any switches that I do not use on a particular model just to prevent accidental flipping of the wrong switch and getting a surprise...

matada34

I still havnt got the gear out of the box since I had it returned, I will install it all tomorrow and take all this into account.

Im very gratefull for all this advice, the one major thing that is confusing me..... how can this happen to 2 seperate rc systems at pretty much the same time!? The 2 systems worked fine previously and were not interfereing.

Thanks again, Matt

V2PLUS10

I'm not sure what to say about that. You have to find a common denominator between the two systems and look there....Just be sure you understand the radio's and their programming. Spektrum/JR is different in many ways from Futaba, and the 6i is different in some ways from the DX-7. Go over everything thoroughly. I do not have either of the rx that you refer to, but I do use a DX7 and have for several years now and really the only problems have been the ones that I have created in one way or another. There were six or seven flyers today at the field. All with 2.4ghtz of one form or another and there were no issues....

Randy

electricpete

I have been using the 9c with the spektrum module for about 2 years now, but recently has a failure, which I now suspect as battery related, so I bought a 6i for my non complex model, and use it suceesfully. After the failure I sent it back to horizon and they reported NFF.

Peter

airbusdrvr

This is not true for JR/Spektrum systems. In fact, deciding what the airplane does with loss of transmitter signal is part of the initial setup when installing/binding a new receiver. After engine shutdown in the pits, I often turnoff my X9303 transmitter prior to turning off the receiver.

matada34

I thought I would add a little update to this and see if anyone has any ideas....

All the rc gear went back to Spektrum, no issues were found. I have since set the model back up and flown etc... all seems ok.

but.... I recently set my friends model back up, I found that all i needed to do was put the servo horn back to the correct position (about 180 degrees out) and all was fine. The mix hadnt changed.

So.... my current thoughts are that, the mix in the TX actually hadnt changed (I was getting confused) and all that it was was that the servo had lost its centre position. With it turning through close to 180 degrees when I put, eg elevator in the mix seemed to be wrong but as a matter of fact it was wrong due to being 180 degrees out. This made it look like it was opposite?! Hope this makes sense....

The servos were cheap micro servos, has anyone had any issues of servs loosing there centre position? Still very odd how 2 different setups can do the same thing at the same time though!

Any thought would be appreciated.

Zeeb

My Feedback: (41)

A couple of thoughts related to the fact that trouble shooting should always begin with the simple stuff first;

95% of the problems with the Spektrum/JR 2.4GHz radios are power system related and electrics are especially vulnerable do to the vast differences in equipment and capabilities mostly relating to the BEC section of the ESC but cold solder joints, bad connections, bad components including servos and insufficient battery size or charge state can also be issues. Make sure the power system is adequate i.e. no flashing lights on the rx's at landing.

One of the other issues I've seen identified especially with new users, is the un-intended depression of the bind button on the DX-7 while turning it on. Usually that happens while the tx is sitting somewhere and turned on to check something on the model. That possiblitiy is more remote with the DX6i as is uses the trainer switch for bind mode, but must be considered as a possibilty. Doing that without the rx being in the bind mode will cause problems.

Franco2fly

I too, just made the switch from Futaba gear to Spektrum.  I have worked in Communications for many years and I liked the way Spektrum picks frequencies from across the spectrum.  That said, my second concern was the "Park-Fly" range versus Full range.

I have several Spektrum radios now (It drives me buggy when folks call transmitters, radios - radios or more correctly receivers go in the airplane)  only one of my receivers is the park fly variety...  if you keep it on the micro flyers, your fine since the plane will be out of sight and you will still have control.  On the other hand, putting a 6110 in a glider that can hook a thermal and be well up there might be if'y.  For this reason, I have started purchasing only AR6200's as they have the seperate RF module to ensure a solid link.  Having two antenna systems in different orientations is a huge advantage especially with 2.4 gigs.  Yea, I know its an extra 30 bucks, (Prolly 15 pounds for you), but the anxiety level is reduced greatly.

Also, pay attention to the light show.  Transmitter on, then receiver on, and steady or solid light.  Quit and shut down in the opposite sequence.

You can simulate a link break by pulling the power on the receiver  then reconnecting but keep the transmitter on.  Now the light should flash indicating a break in link.

KKKKFL

BuschBarber

My Feedback: (2)

This year was the first time I realized the disadvantages of having such a prominent Bind Button on the back of the DX7. I leaned the Tx back against the Side Rail of one of our Starting Benches and little did I know that the Bind Button was depressed by the weight of the Tx. When I turned on the Tx, the Bind was lost. I did a ReBind and set the Tx in the same place, only to have the same thing happen. I finally realized what was happening. I taped a protector over the Bind Button so it will not happen again.