PETER BRUCE - Eastchurch Gap Posted June 5, 2016 Share Posted June 5, 2016 Lost two planeS with my DX6 - both incidents same day and I had a camera fitted to both planes with two images - front and rear video - no inputs worked and the engines did not go to idle. Tx sent back to Horizon. Seemed like a range issue as both planes went in about the same (close) distance away. Use Spectrum Rx - no problems in the past with either of the models... I shouted out a warning as soon as the planeS became unresponsive. Videos can be seen here on forum video channel. Plane Crash 1 and Plane Crash 2 is another entry a few down. Have a look and see - no elevator input at all - I was trying like hell to no avail... Totally Gutted. Edited By PETER BRUCE - Eastchurch Gap on 05/06/2016 19:41:51 Quote Link to comment Share on other sites More sharing options...
Don Fry Posted June 5, 2016 Share Posted June 5, 2016 Posted by ben goodfellow 1 on 12/03/2016 16:49:49: hiya,,,,,,,,,and good luck from me .who knows if you will have problems ............maybe not .......though quite a good chance you will........you just dont know.............. fly low Say something Ben. Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 5, 2016 Share Posted June 5, 2016 It's the not knowing that worries me most - if there is a problem I can live with that but if it comes back as "within design perimeters" I don't know how I will react to that... Got to wait and see. Quote Link to comment Share on other sites More sharing options...
Steve Colman Posted June 5, 2016 Share Posted June 5, 2016 Odds are that it will be returned to you with with something along the lines of "We couldn't find a problem but we've changed the RF board for your peace of mind" Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 5, 2016 Share Posted June 5, 2016 Just for interest I had checked out the RF between the standard DX6 before it went back and a plug in the rear module for my Futaba FF9 and the output RF power on the latter was over four times more output at 12 Mtrs range... I used my Tenmars 3 axis RF field strength meter model TM-195 which is calibrated (4/2/16) and can cover from 50Mz to 3.5 GHZ. The Futaba unit was an import which is why I have not used it however I can't explain the difference in radiated output RF if all the Tx are supposed to be at the same output power levels... Quote Link to comment Share on other sites More sharing options...
Martyn K Posted June 6, 2016 Share Posted June 6, 2016 Posted by Dave Hopkin on 12/05/2016 11:17:27: Control surface reversal - I have experienced that on Taranis (once) third or fourth flight of the day (so the model set up was not disturbed at all) connected LiPo flight battery - usual pre-flight waggle, Ailerons reversed..... Flipped channels 4 and 5 over to correct the orientation on the TX, rest of the day it remained the same way ever since..... Still dont understand why..... I have seen that as well. Latest was yesterday when I spotted the rudder (on a well proven model - my Curare 25) was reversed (but this was first flight after EU-LBT upgrade). Also had it happen on another model where the Ailerons (and on a separate occasion the elevators) reversed - despite earlier in the day checks witnessed by another showed that they were correct. At first I thought I was going mad and didn't want to confess... Now I am paranoid about checking control surfaces which probably isn't a bad thing Martyn Quote Link to comment Share on other sites More sharing options...
ben goodfellow 1 Posted June 6, 2016 Share Posted June 6, 2016 Posted by Donald Fry on 05/06/2016 19:50:25: Posted by ben goodfellow 1 on 12/03/2016 16:49:49: hiya,,,,,,,,,and good luck from me .who knows if you will have problems ............maybe not .......though quite a good chance you will........you just dont know.............. fly low Say something Ben. hey lads come on , i mean theres nowt wrong with dx6 .................or the 8 or 9 or 18 ,, all these crashes are bad set up ,pilot error , brown outs and all the other reasons that people with there head in the sand and thumbs somewhere else come up with ...we all know spektrum never has problems and probaly never will....fly low Quote Link to comment Share on other sites More sharing options...
Pete B Posted June 6, 2016 Share Posted June 6, 2016 I knew you'd see the light eventually, Ben Pete... Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 6, 2016 Share Posted June 6, 2016 Me thinks best way forward is to see what Horizon say. Not fair to assume the worse until I get the test report back. Only think I am still miffed at is the massive difference in radiated RF between the Spectrum 2.4 unit that plugs in the back of my Futaba FF9. Why has it so much more output power!!! See above for the test equipment used... Can anyone explain... Regards Peter Quote Link to comment Share on other sites More sharing options...
ben goodfellow 1 Posted June 6, 2016 Share Posted June 6, 2016 yes ive seen the light pete ..................fortunately its a blue one on a futaba 18 sz ..................fly low Quote Link to comment Share on other sites More sharing options...
gillyg1 Posted June 6, 2016 Share Posted June 6, 2016 good old spectrum again, never used it never will, after my mate lost 3x aircraft with the then new 6i, he has now changed to graupner. And to hear the new 6 has problems, thank goodness for futaba. funny how there's always a lot of specky radio's for sale second hand, can't tell me there all upgrading, selling it for a deceased friend, giving up etc etc. Quote Link to comment Share on other sites More sharing options...
Masher Posted June 6, 2016 Share Posted June 6, 2016 Posted by PETER BRUCE - Eastchurch Gap on 06/06/2016 17:33:37: Me thinks best way forward is to see what Horizon say. Not fair to assume the worse until I get the test report back. Only think I am still miffed at is the massive difference in radiated RF between the Spectrum 2.4 unit that plugs in the back of my Futaba FF9. Why has it so much more output power!!! See above for the test equipment used... Can anyone explain... Regards Peter Peter As you are probably aware, it is very difficult to accurately measure these type of signals. I know nothing of your test kit but, for example, your FF9 module could be chucking out loads of spurious which are distorting the total power reading. Even using the best equipment requires great care and some knowledge of what the spectrum/spektrum is actually doing Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted June 6, 2016 Share Posted June 6, 2016 I know just enough about spread spectrum transmission to realise that I know almost nothing about the subject but Peter's rudimentary testing does suggest that there may be a significant difference between two units designed to work at the same power (assuming it isn't a US market version) on the same version of spread spectrum - especially if, as I think is implied, the module is a genuine Spektrum offering? We may sometimes jest about the "changed RF board" response but perhaps there's some truth in it? Edited By Martin Harris on 06/06/2016 18:47:27 Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 15, 2016 Share Posted June 15, 2016 UPDATE Contacted Horizon today (15th June 2016) and they will be sending me brand new DX6 transmitter. Can't be fairer than that can you... Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted June 15, 2016 Share Posted June 15, 2016 What slightly concerns me is the readiness to change equipment on the say so of customers - it suggests to me that the company may be aware of common problems. Or maybe they're just thoroughly nice chaps! Quote Link to comment Share on other sites More sharing options...
ben goodfellow 1 Posted June 15, 2016 Share Posted June 15, 2016 peter ... did they happen to mention if there was a problem with the first one you had ? Quote Link to comment Share on other sites More sharing options...
Pete B Posted June 15, 2016 Share Posted June 15, 2016 It may have been something as simple as Tx orientation, Peter. The initial production of the new DX6 (DX6G2) had only one antenna, set vertically in the stubby moulding. Since then, Spektrum had a re-think and last year released the DX6G3, with a second diversity antenna, as with the DX9 etc range. Fitting only one antenna was a pretty inexplicable move by them, I must say, as there's a very strong probability that the Tx will often be held in such a way as to point the antenna at the model, which is the last thing you want to do.... I'm sure you'll be getting one of the latter and hopefully will see a better, more omni-directional output. Pete Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 15, 2016 Share Posted June 15, 2016 Please remember that I was able to supply them with on board video evidence of both crashes showing the exact instance leading to the crash which clearly showed no input commands getting to the elevator of BOTH planes. As we are a coastal site perhaps I was hit by S or F band radar which is in 2.4 = who knows... Regards for your valid comment. Peter Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 15, 2016 Share Posted June 15, 2016 I was told there was nothing they could find wrong with my original DX6 but they were going to change the right stick pot just in case but as there was a delay to get the parts they have sent me a new unit instead. Can't be fairer than that. Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 15, 2016 Share Posted June 15, 2016 Hi Pete B. I did read they had changed the antenna to a dual system. When I fly my model I do hold my tranni as I would normally do so you have a point as the aerial would be pointing at the model a lot of the time but its never been an issue before with any other radio I have had. 35mHz would even see round corners but 2.4 is more line of sight. I would dearly like to know what happened to both my models but alas looking at both videos over and over again just gave me a headache so I will put it behind me and start again. I did also provide the link to both videos for Horizon. Just out of interest all my gear was Spectrum and not obtained from eBay as I am fully aware of the implications... Quote Link to comment Share on other sites More sharing options...
Martin Harris - Moderator Posted June 15, 2016 Share Posted June 15, 2016 Have you flown successfully with the same twin video set-up? Were they streaming or recording? Just thinking out loud... Quote Link to comment Share on other sites More sharing options...
PETER BRUCE - Eastchurch Gap Posted June 15, 2016 Share Posted June 15, 2016 Hi Martin. Flown with the camera on a number of times and its NOT WiFi just straight recording to card. I had done some tests on low power at the extent of the range then moved back a smidge and turned on the camera but got no difference in range performance. Also did a sweep of the camera with a scanner (50 mhz to 3.5 ghz with no recorded RF output. I think the single antenna could have had something to do with it - although all my models have the aerial pocking out of the sides of the fuzz so as to give clear view to Tx... No clues there. My Tx was very low hours _around 10 if memory serves me - and it was only just a couple of days withing the guarantee when I sent it off so it was good of them to change it for a new one... Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 16, 2016 Share Posted June 16, 2016 I fly a JR DSX9 with a single antenna and have never had so much as a glitch, but this is always angled upwards towards me so that I would need to be flying behind my head for it to be pointing towards the model. I cringe when I see antennae pointed sideways because the model will receive very little signal in that direction. Just like aiming a 35mHz aerial at the model. Manufacturers should make this point clear. I have several other 2.4 sets and there are never any guide lines to this. Quote Link to comment Share on other sites More sharing options...
Martin McIntosh Posted June 16, 2016 Share Posted June 16, 2016 Interesting to read about control surface reversal. At the Nats, when they allowed evening flying on 2.4 I was the first one to go with a Cap 21 on a DX6 (DSM1). Crump! Ailerons suddenly reversed. Besides the DSX9 I also use a Taranis and a TGY i10, both of which now perform immaculately in the air other than on the first outing with the i10 which was installed in three models. The first suffered aileron reversal on take off despite this being checked and one of the others had a throttle reversal (electric) before take off which would be difficult to get wrong in the shed. Could this be due maybe to static electricity from my hands affecting the gear? A mobile phone? Thankfully no problems since then. I have heard of quite a few problems reported with Spektrum using Orange Rx`s but I have quite a lot of these in use with my JR DSX9 with no issues whatsoever as yet. In fact I use the excellent 9ch. in some of my scratch built scale models. Quote Link to comment Share on other sites More sharing options...
Peter Beeney Posted June 17, 2016 Share Posted June 17, 2016 I have written this in a previous thread before so it is getting on a bit, but I’m sure it still holds good to some extent. And hopefully it might have some relevance to this this thread, or at least be another point of view. We have a little procedure, (2.4GHz), for doing a full range check which consists of placing a rx, battery and a couple of servos on a metal framed folding chair at the patch and then taking the tx to a point some 750 yards away; still direct line of sight though, across a shallow valley and immediately in front of a small wood. The rx aerial(s) are configured to point directly at the tx, (worse case), and just to make it a bit more interesting three more switched on transmitters are placed directly under the chair. The strip is in between, and often there are flying models there, too. Mobs are used for comms at both ends, close to the radio units. Checks for correct operation we do with the tx held normally at waist height but with the aerial pointing in every conceivable direction, including back-to-front, pointing directly away from the receiver; and we also have a few minutes idle period to see if the servos might twitch in sympathy with the very close range transmitters. I have to say that in every case each rx/tx combo behaved impeccably, not a single misfire between them all. It started when we wanted to find out how good, (or bad!), the Assan 6 channel micro rx was, this doesn’t exactly give the appearance of being the worlds most impressive receiver, there's hardly anything of it and the aerial is what just seems to be a piece of of wire three quarters of an inch or 18mm long sticking straight out from the PCB. But nevertheless…it did indeed set the gold standard; and it’s gone on to continue to perform immaculately ever since. Spektrum is included this, as it happens, my old DX5e with an AR500 rx, this performed exactly as any of the others. I don’t consider this to be be any sort of definitive result at all, but at least as far as we are concerned aerial orientation is not always strictly an issue. Or transmitter/foreign receiver interaction, either. Graupner state that, in theory at least, 200 transmitters will work together in harmony; and indeed quite importantly, a standard sports model at 750 yards close to the ground is just beginning to get a bit of a test on the old minces; at that point I’d tend to think that radio reception is fast becoming the least of my worries. Taking my usual sideways view of everything, I’ve also used the Spektrum in other little experiments, such as making the radio installation in a powered glider as incorrect as as I possibly could and then flying it, gradually, to the limit of visibility. As with the range tests, it was a total anticlimax, not even a tiny miscue. It flew like this on a number of occasions, so once again I had to conclude that the radio can sometimes operate ok under what is usually perceived to be unfavourable conditions. Whilst on this subject generally, back in the day there was an unfortunately very serious incident and we didn’t quite understand all the info that followed it that was being discussed about PCM radio. Much like 2.4 now. So we did our own practical in the air interference tests. To be brief we found that two interfering transmitters together had only the same effect as one and then after some tentative efforts and some practise I found I could tolerate the interfering signal for a few minutes at the time, although the model would always eventually reach the ground. One interesting aspect I did discover very early on when I was setting this up was that the Futaba Field Force 7 that I was using sent a failsafe update pulse to the receiver every minute or so; the failsafe settings being done from the transmitter. On switch on the first pulse was sent and if I then delayed slightly when switching on the rx this didn’t get the failsafe instructions for a period of time, up to forty - fifty seconds, say. This was probably ok with i/c, by the time you’d started the engine and done checks etc. the second pulse had been sent, but I was easily able to to demonstrate with my model, a hotliner with separate rx battery, that it was possible to take off before the second pulse! So no failsafe on the radio for a while. Not a good idea. I think the chances of this ever being the cause of an incident back then were extremely remote anyway, but if it ever had been so, unless you explicitly knew about this, any subsequent checks would have invariably revealed the failsafe to be operating ok - apparently! The whole episode also drew a rather dry comment from a very experienced helper at the time, who is also a good mate, “ It’s for sure that PCM radio don’t always behave like wot it’s suppose to!” We haven’t done the 2.4 range checks for a while, no requirement really, but if we ever do we can upgrade a bit, such as turning the receiver around into different positions as well etc. But I can’t really see that having very much effect either. Only just another ramble and perhaps of not much use really, but at least as far as I’m concerned it does answer some questions… PB Quote Link to comment Share on other sites More sharing options...
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