Ken Tarran Posted October 26, 2015 Share Posted October 26, 2015 Hi All, First of all let me describe the servo setup of the Me108.... 2 Elev servos 1 Rudd servo ! Thro servo 2 Ail servos 2 Flap servos 1 Retract servo I have the 2 Elev servos with Y leads to the Rx, the 2 flap servos with Y leads to the Rx and the 2 Ail servos with Y leads to the Rx. On the DX6, in Aircraft Type in System Setup I have set it as Wing: 1 Ail, ! Flap, Tail Normal. If I don't have the Ail or Flap plugged into the Rx, the Throttle, Rudd, Elev and Retract all function correctly. If I then plug one ail lead into the Y lead, that functions ok, as does one flap similarly at he same time. As soon as I plug the second Ail lead and/or Flap lead into the Y leads, the servos have a mind of their own and the elev doesn't work properly either. They all start flapping about and the orange light on the Rx starts flashing too. I had this model previously setup on a Futaba T6EXP Tx and a Futaba R136F Rx and all worked without any problems at all. I bought the DX6 in order to gradually move my models onto 2.4ghz and take advantage of the model capacity of the DX6. Has anyone any ideas as to what could be causing the issues I'm experiencing. I have tried various different settings in the Aircraft Type without any success. I have now come to a dead-end and don't know what to try next, other than return the model to Futaba radio which defeats what I set out to do. If you are able to throw any light on my problem I would really appreciate it. Kind regards, Ken Quote Link to comment Share on other sites More sharing options...
gangster Posted October 26, 2015 Share Posted October 26, 2015 Wow that's not good. The fact they start thrashing around could be a voltage issue have you plugged an on board voltage checker in at the same time and seen what that says also battery straight into rx dont think it will have any bearing this time but what I have done in the past when I am banging my head against a brick wall is to move onto another memory slot just in case there is a crazy mix sitting there Quote Link to comment Share on other sites More sharing options...
Former Member Posted October 26, 2015 Share Posted October 26, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Ken Tarran Posted October 26, 2015 Author Share Posted October 26, 2015 Hi Steve, I have two Tornado batteries in the model (separate one for the retracts) and both are Tornado 2000 and both are reading 6.8v 99% full on my battery capacity checker. Ken Quote Link to comment Share on other sites More sharing options...
Dave Hopkin Posted October 26, 2015 Share Posted October 26, 2015 I wonder if you have a duff servo dragging the power down? I would unplug all servos and gradually try each on singly to see if its ok, then try Alis on their own, then flaps on their own, then flaps and Alis together, if still ok, then add the remaining servos one by one Quote Link to comment Share on other sites More sharing options...
Former Member Posted October 26, 2015 Share Posted October 26, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Ken Tarran Posted October 26, 2015 Author Share Posted October 26, 2015 They're both 5 cell NiMH batteries and are a couple of years old. I've disconnected the arms from the servo horns on the two flaps and the two ailerons to ensure there isn't any binding on the linkages which may have caused a servo overload. This has made no difference to the servo operation on all of them. When I have the THR, RUDD, ELEV all the time and then connect the two AIL leads into the Y lead to the Rx, all function OK. Then when I plug ONE flap lead into the Y lead from the Rx, everything still works OK. When I plug the second flap lead into the Y lead that's when the ELEV, FLAP and AIL start misbehaving. Conversely, if as above, after plugging in the THR, RUDD, ELEV and then connect the two Flap leads into the Y lead to the Rx, all function OK. Then when I plug ONE AIL lead into the Y lead from the Rx, everything still works OK. When I plug the second AIL lead into the Y lead that's when the ELEV, FLAPs and AILs again start misbehaving. Hope that helps to explain my dilemma - fly with one flap or one aileron perhaps?!? By the way I don't have a voltmeter to check what's happening as you suggest. Kind regards, Ken Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted October 26, 2015 Share Posted October 26, 2015 Do you have a mixture of digital and analogue servos, perhaps? Quote Link to comment Share on other sites More sharing options...
Simon Chaddock Posted October 26, 2015 Share Posted October 26, 2015 Ken Does it all work ok with either of the aileron servos connected to the Y lead? If it does then it would confirm that the wiring and the servos themselves are not to blame but it is the act of adding the second servo that is causing the problem. The fact that the other servos start to misbehave certainly points to a voltage issue caused by an increased electrical load. Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted October 26, 2015 Share Posted October 26, 2015 Are you using Towardpro servos via a Y lead. If you do, then that's the problem. Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted October 26, 2015 Share Posted October 26, 2015 OK, I have seen similar before when I tried to plug too many servos into one port on one of my (non Spektrum) receivers, for the servos to work they need power (+ve and -v rails) but they also need to be able to see the position signal, now if you hook up too many servos to the rx you maybe overloading the position signal output, which is fine for 6 or even 7 servos but when you go over the "strength" of the position signal becomes too weak. This will be a function of the chip inside Rx and it maybe that your Futaba Rx wasn't quite as sensitive and could supply the required position signal to that many servos. Interestingly a friend with a Futaba system had problems with a set of E Flite retracts which wouldn't work when he Y leaded them together with an existing Y lead, but they then worked fine when he used the supplied Y lead which had an inbuilt signal amplifier. Your only way round this maybe to do the same with your aileron and flap channels, the special Y lead is the EFLY H9 Dual Plug Y-Harness. I must admit I try to avoid using Y leads wherever possible, but as you've only got a 6 channel Tx/Rx you don't have that option. Quote Link to comment Share on other sites More sharing options...
Paul Marsh Posted October 26, 2015 Share Posted October 26, 2015 ...buy a DX 9 would make life easier. Quote Link to comment Share on other sites More sharing options...
gangster Posted October 26, 2015 Share Posted October 26, 2015 Ken. You say your battery checker says 99%. But have you plugged it into the rx when the servos are connected? Quote Link to comment Share on other sites More sharing options...
Ken Tarran Posted October 26, 2015 Author Share Posted October 26, 2015 The AIL and Flap servos are Supertec S03 and the RUD, THR and ELE are Futaba FP-S148. Quote Link to comment Share on other sites More sharing options...
Former Member Posted October 27, 2015 Share Posted October 27, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Ken Tarran Posted October 29, 2015 Author Share Posted October 29, 2015 First of all let me say a big THANK YOU to all of the above RCM&E Forum members for giving me their thoughts and possible solutions to the problems that I described at the top. Today, I took the model and Tx to Martin at Whitchurch Models (Martin is the owner by the way) at his very kind offer and suggestion after spending a lot of time getting nowhere at home trying all sorts of combinations and connections both on the model and DX6. To cut a long story short, Martin, using a process of elimination, finally tried a brand new Overlander 6v Rx battery on the Me 108 which immediately cured the problems I had been experiencing. I wasn't able to do this at home because I didn't have a new battery and I was reluctant to start replacing servos, switches etc etc spending a lot of cash until I was sure what the problem was. Martin was able to do this in his shop and I am eternally grateful for his help and expertise. Whilst in Whitchurch Models, a customer who had been watching and listening to the diagnosis revealed that he changes all his Rx batteries for new ones at the start of every flying season. Some may say that that approach may be a little OTT and extreme but he certainly doesn't get any RX power issues/glitches and there may be a moral in the story there for some of us. Anyway, I can now concentrate on getting the model back together again (with new batteries) and reinstating all the various settings on the DX6 that I'd been messing around with!! Best regards, Ken Quote Link to comment Share on other sites More sharing options...
Ken Tarran Posted October 29, 2015 Author Share Posted October 29, 2015 Steve, Regarding your suggestion about using a 7mm segment voltage meter on my model - how would this be connected to the Rx given that all the sockets are in use on the Spektrum AR610 Rx? Ken Quote Link to comment Share on other sites More sharing options...
Frank Skilbeck Posted October 29, 2015 Share Posted October 29, 2015 Posted by Ken Tarran on 29/10/2015 16:29:40: Steve, Regarding your suggestion about using a 7mm segment voltage meter on my model - how would this be connected to the Rx given that all the sockets are in use on the Spektrum AR610 Rx? Ken Just use a Y lead either on the Rx battery feed or any other servo, the +ve and -ve at the Rx are on a common rail. I Quote Link to comment Share on other sites More sharing options...
Former Member Posted October 29, 2015 Share Posted October 29, 2015 [This posting has been removed] Quote Link to comment Share on other sites More sharing options...
Don Fry Posted October 29, 2015 Share Posted October 29, 2015 I can think of at least 3 battery purchases which did not get as far as a flight, I mechanical failure, and 2 test failures. And if they pass the test, why bin them. My record was a ripmax brand nicad wot lived in a junior 60. I decided to sell the plane, but before sale I tested it . All good, and at least 20 years old.. When something gets made, no one loves your new pride and joy, you get to test if they actually hated it. Quote Link to comment Share on other sites More sharing options...
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