The radio 's have a bind buton on the back once depressed it cuts power by half ,you should be at about 30m or 30paces before you loose response , no there not meant to take off by them selfs

O.K., I'm drooling, ya got a spare room so I can come down and fly? Here in CT, USA the biggest field is about 150' of runway. Realesate is precious around here, funny though, the feilds are always surrounded by acres of woods and a lone neighbor about a mile away who complains about the noise, go figure.

What you said sounds like the problem and also someone setting down a transmitter with the plane unrestrained, is totally bonkers(asking for an accident).

What you also need to understand wheather it be a 2.4 system or 72 they are not surface radio systems, when you get them that close to the surface of ground they will do funning things. I have seen it with 72 also.

I would like to add that I also had problems with a 72mhz radio. I had the receiver installed in a scale Cessna, and when ever I switched the plane on, the surfaces would twitch like the plane was having a seizure. When I changed the routing on the antenna slightly, the twitching stopped. I then switched on the radio and started the engine. This time, the surfaces would twitch when ever I opened up the throttle. So, I monkeyed again with the routing of the receiver wire and solved that issue. I then flew the maiden, and this time I would wind up the engine and the plane would start doing axial rolls, but stop when I slowed the throttle. I brought the plane back in, took it home, and examined it more closely and observed no problems.

In subsequent flights, some crashes were related to control surface trim issues which were fixed. Cosmetically, the plane didn't look the greatest but performed reasonably for a second plane. Then, one training night I was doing a few stall turns and the plane acted real funny. It suddenly nosed up, and the engine behaved odd. I couldn't recover, so I controlled the crash in the bean field as best I could. The weather that day had several periods of rain, and I think this could have had an effect on the receiver. Another club member told me that the crash was due to pilot error: Flying the plane too slowly. I'm convinced that it was likely a combination of radio problems, and not enough airspeed to recover.

Any radio will cause problems if it's not properly set up, regardless of the type. Our club has never had a problem with JR Spectrum equipment that I'm aware of.

NorfolkSouthern

Yep - got to love the old guys and their "sky is falling" rhetoric regarding 2.4. They must find it hard to keep up with all the new fandangled stuff available these days - imagine, moving pictures in a box, instant on lighting and a horse drawn buggy without a horse . I have had 2.4 since it was available and have never had an issue with it - IF properly set up. I had a plane once that was playing up a bit in the pit area. All the old timers came over and pointed a stick at the 2.4 and danced around proclaiming that it was evil - there's no antenna poking out the top. Much to their displeasure it turned out being a faulty battery switch. Where i fly there is always somebody proclaiming radio interference for their mishap, problem is it's usually the interference from their brain to their thumbs.
Check batteries - change to 6V if necessary, and just make sure your failsafe is set to idle (turn off the transmitter keeping the plane on and see where the throttle goes to). Have fun and fly.

Had this problem when all high power digital servos used
Even with a fully charged 6v 2500mAh (AA) batteries
Found this when I was bench testing
Even in same room, after awhile with radio on it would fail safe

Digital servos seem to draw a lot of current even at neutral
With the 2500mAh 'AA' batteries and 5xHitec HS5645 servos, it barely lasts a minute before they cannot maintain the current demand
sub 'C' cells last a bit longer, but I always use Li-Po and regulator with any digital servo setup now

I've had the Li-Po(2200mAh)/Reg setup and left radio on for an hour with no problem

our flying site is in a UFO hotspot. i keep tellin these guys that is the problem with their new fangled radio's but they won't listen. when UFO'S have been in the area all those 2.4 radio's go nuts for at least 24 hours until after the weird glow disappears. so i'm sticking to my 72 mhz radio's.

Not trying to start chevy vs ford thing here, but.

If Spectrum is so good, how come they come out
with a New version every Month or so ?
How come they use 2 Antennas ?

I use 2.4, but it's made by the company that has
been around longer than I have. I'm 51 and no
I don't work for them.

Bob

I always wonder about guys when a person posts a question and all the nay sayers jump on the bandwagon with little or no relative input or suggestions.

A couple of thoughts here;

First, I agree that what the OP did was not a good idea.

Second, as has been mentioned setting the tx on the ground with a model that far away probably isn't a good idea either due to the factors already mentioned.

Third, this is sounding like a battery issue with the model. Virtually every problem with the Spektrum/JR 2.4 systems I've seen where the actual cause could be identified turned out to be power issues. There were some intial issues with the 6100 rx's and un-commanded servo operation in certain circumstances, but that was fixed with an update quite some time ago.

It sounds to me like the model experienced a power brownout and the rx shut down. It also sounds like perhaps the latest Quick Connect update was not installed on the model's rx. That is the one where if a power brownout is experienced and the rx shuts down, it will come back up within 1/2 second of power being restored. It also sounds like the OP did not do a bind after the model was setup. If one reverses the servo travel on say the throttle servo and does not re-bind, when the rx is first powered up it will drive the servos to their low travel points. If it's not done after setup the rx does not know the throttle servo is reversed and will drive it to full open, then when it links with the tx it will pull it back. If this is the case and the model has not be re-bound after setup and the Quick Connect firmware is not installed, what happens is this:

The rx shuts down relieving the power drain on the battery, with no load the battery quickly provides enough power to re-boot the rx. When it comes back on and is not yet linked with the tx, it will drive the throttle servo to wide open until it links with the tx and that will take 2 to 5 seconds if the Quick Connect is not installed. That time frame could be longer with the tx sitting on the ground.

I think that may be what happened but the OP will need to verify if the Quick Connect firmware was installed on his rx, whether or not the throttle servo travel was reversed, and whether or not he did a re-bind after setting up the model.

I agree that the provided 4.8 volt NiMH batteries are not the best way to go and wish the manufacturer's would supply better batteries, but that is very much an individual choice for guys so why spend more money on a radio set with batteries you don't want? The 4.8 volt rx packs will work but you really have to keep an eye on 'em. The low voltage threshold for the Spektrum/JR system is 3.5 volts so there's not a lot of overhead to work with when the servos start pulling power. Some NiMH batteries, particularly the AA size can have notoriously high impedence, or internal resistance, and will really drop off on the voltage when a load is put on them.

IMHO, guys have been getting away with inadequate power systems for years and when the 72MHz system shuts down and comes back on it's nearly instantaneous, so I think low voltage problems are the main reason one used to hear "I got hit!" from the flightline. With the new Quick Connect firmware, the Spektrum/JR 2.4 rx's will re-connect witht the tx in about the same time as a 72MHz system or possibly faster, but that's not a reason to underpower (electrically) a model's flight pack. The new Quick Connect firmware will also tell you if you've experienced a power brownout by displaying flashing rx lights on landing if one has occured.

It would be great if the OP could check some of the items I've mentioned and let us know what he finds?

i have a freind who works at our lhs and flys helis in competitions with another club mate that is in the british display team,i am only telling you this to let you know that they are very,very good at what they do just so you dont think that what i am going to tell you next is down to pilot error.
the one that works for the lhs brought the new futaba 12 channel 2.4 set up at a cost of £850 to fly at comps, while flying his slot the collective reversed itself in flight sending his heli smashing to the ground after rebuilding it and putting it down to pilot error he flew again needless to say with the same in flight result after which they stopped him flying with that rc set up
he has now changed to spectrum gear.
this is the second person that i know that has regreted going to 2.4 at his cost (after loosing three planes in a day)
as i fly jets i cannot afford or want to increase my chances of loosing it in a crowd, this technology was supposed to help not put more doubt in our heads about safty.
its has not proved itself to me yet

Hello,

Their is guy at our field with very solid and legitimate Electrical Engineering credentials (Pls Trust me on this). I asked him.

I hope I have this correct , but this is what he said. ( I am the messenger, not the author of these comments)

1) Loss of signal will cause Spectrum Rxs to go into failsafe . So the first explanation in this post is probably correct. This also sounds like the failsafe settings are set incorrectly. He says this is common.

2) Antenna orientation is also an issue. The configuration of the field generated by the Tx is not uniform in strength nor is symmetrical. So there are blind spots. The number and size of these blind spots diminishes rapidly as one moves further away from the Tx.

The proximity m( of the tx ) to the ground is also an issue but very small. Measurable( by instruments) but very small. Probably effectively zero due to the redundant Rxs. But Tx Antenna orientation to what the four Rx antennas see is not zero. He says that is why there are four of them and some systems more than two Rx's.


3) Now here is the new news. The Rx can be swamped if the the signal strength is too strong. He says he can induce this by brining the Tx very close to the two rxs in a certain antenna orientations. And thus he can prove it. This was well know to the designers of the programming in the Rx and the failsafe was designed as a remedy.

4) All of this said, he then said 2.4 gig systems are VASTLY more robust and reliable than 72 mg hertz. Without question. With failsafe properly initialized you should not experience any meaningful amount of problems. But it is not zero.

5) The early Rx had a reboot time after coming of failsafe mode of 8 to 10 seconds . This was a problem and was fixed a long time ago . He says Spektrum was replacing the old ones with new ones which rebooted much much faster - so that it is now almost imperceptible. And they also had a low voltage cutoff ( that caused a reboot which compounded this) into failsafe which was also fixed. Both of these mimicked lose of connection but were in fact not.

I hope I have done justice to my friends explanation I have tried to relate them as accurately as I could. His request for anonymity I believe is legitimate - but I cannot swear to it. He does not work for JR , Spectrum or anybody else you or I can think of.

I hope this has been helpful.

A.

Delete

You should no expext 120 meters range when both model and radio is placed on the ground. No matter which radio system! I agree in the failsafe theory, due to this...
If you did put the TX 1 meter above ground you get many times the range.

You srtart out by saying"Not trying to start chevy vs ford thing here, but." If your sentance ends with a but then Yes you are trying to start something.

As for the company that has been around forever they have had a lot of problems due to heat failures with their recievers, I know of one personally a friend lost his comp arf due to the crap he bought. So if you think that any system has no problems then I have a piece of property I would like to sell you.

I would rather have 6 antennas if the signal between my transmitter and reciever is better than your 2 or your nub.

Issues resolved 1. the plane set up Servo's 5 DS821 diitals 1 HXT 900 gram ( throttle ) Batt 4.8v ni mh 1600 mah RX AR 7000 Tx DX7
2. There is no quick reset installed ( I have been told that spectrum install this for free, I just have to send the rx back )
3. No rebind after plane set up eg. reversed throttle servo after binding
This resolves a lot of questions the set up of the plane and radio was incorrect, which turns out to be an expensive lesson on my part. I will also change the on board batt to 6v amybe 2600mah.
I have had the DX7 about 6 months now and love the tx and it's programing. I have 6 Ar 7000 rx and 1 AR 6000. All will be going on the bench to recheck set up. I have noticed that the lattter purchased RX units have the quick connect insralled. eg when radio and plane both on then radio switched off, then the radio turned back on the rx lights start flashing. This all happens in about two seconds.
Cheers for the input guys

I feel for you dude, we are fortunate at the club both for the field we have and the guys I fly with, I have only every flow at this club. so sort landings no obsticles would be another thing to deal with. If you every in Aussie you should drop by

Yes, good thing this was'nt a 100cc gasser.

Craig,

Excuse my bad Grammer please.

Bob

Well done basman - glad you worked it out. Try going to the new Sanyo Eneloop batteries - 6V 2000mha. There are pre wired for JR / Spektrum receivers and have an excellant reputation. They should be available from most good hobby shops. I've been using these in my AR7200, 6200 and new 500 Spektrum rx for a while now with no issues. Live and learn by mistakes - now go fly and have fun while all the soothsayers climb back into their trees.

I guess all that can be said about anything, no matter what it is, is it's not perfect. from my personnel observation and experience I have not had a single glitch in over 2 years. Nor have I heard of anyone in my club having any. Having read these forums for some time I have heard of many incidents regarding 72 and experienced a few over the years. My conclusions therefore are definitly in favor of Spectrum. they have many things in their favor over 72. Model match for one. Strangely unfortunetly every so often something goes wrong with every car I've ever owned, as well as various things in my home. Just don't know why nothing is perfect??? Can't speak for other 2.4 systems since never used them.

So, it boils down to OPERATOR ERROR in the end. He reversed the throttle servo and didn't rebind it.

Why it went into failsafe is anybodies guess.

I like Spektrum and trust it. I made a mistake in setting up my first model with Spektrum and almost lost a $3500 plane. I saved it and figured out why it was not working right. My fault for not setting it up correctly. It's fixed now and rock solid.

Basically:
If you make ANY changes to a Spektrum setup, you need to bind it again.. If you adjust an endpoint, bind it. If you reverse a servo, bind it. If you adjust any sub-trims, bind it.

You bind the system to do your initial setup on the bench. That just gets the TX and RX talking to each other. Then you bind it all again when you're finished dialing it in.

If you make ANY changes to the endpoints, channel reversing, subtrims, etc etc etc...... BIND IT again!!

Go fly it......maiden flight. Use TX trims to establish hands free flight..... flat and level.

LAND IT!!

BIND IT!!

If you so much as SNEEZE at a Spektrum radio, BIND IT again!!

Overkill? NOPE. Pain in the butt? Yup.... Necessary? I believe so.

Crap, if I had to rebind every sensor on one of the chillers Trane makes, everytime I set an offset for a sensor or actuator, I'd be there all day long and still have to return to finish it off. On some of our equipment, we bind it once to identify the part and then continuously update the input and output value and never have to rebind anything. If we had to do that, all our customers would remove our chillers and buy something else.
Getting back to 2.4 gig systems, I still fly 72 MHZ, for cost reasons, but someday 2.4 will be the only thing avaliable, and yes it will expand into the 3+ gig spectrum as new and improved, with that said, I fly airtronics right now because of features and it talks to all my receivers I have right now. I will wait to see what negative comments come from airtronics 2.4 system, I originally started flying with futaba systems, conquest(that dates my age), I went to Hitec for years with no issues, then I went to JR for a few more, till I realized it weighed a ton and had poor programing menu's, so I bought a RD8000 and as luck would have it, they came out with the RDS8000 about 1 month later. But I will wait till I get more resounding proof or piece of mind that it will have aqll the bugs worked out before I stick it in one of my planes. I don't like ARF's too much, so I build my own or kits, nothing is more gut wrenching than losing a plane due to radio issues. Sure it happens to 72 MHZ as well, but the # of "free upgrades" done to a spectrum radio by the manufacture after a major loss doesn't make me feel warm and fuzzy about it.
Just my 2 cents
And Oh yes, I must be one of the old guru's dancing around your spectrum radio chanting "evil spirit radio", at the ripe age of 32, if some of you see it that way. I'm not against progress in technology, but weary to dump tons of money into a system that has apparent issues.

Small world. I'm in the HVAC industry as well. [8D] I'm an estimator for a commercial HVAC contractor. I bid projects with those Trane chillers and rooftop units on a daily basis. I sent out a bid last week for $885,000.oo to do all the CRAC units and rooftops on a 6 story building. It has a bunch of Liebert units and Trane 25ton rooftops with Tracer controls.

I know you shouldn't have to bind every time you touch the darn thing. But I figured out from reading these forums that people are always having problems with these 2.4ghz systems. Seams the culprit can always be traced back to not binding. Not binding after initial setup is complete. Not binding after making changes to the programming. Not binding to set failsafes. I just kinda decided that each time I make a change, I'll bind it again. Even if it's just something as simple as reducing elevator travel from 110% down to 103% .. I bind it again. Anytime I make a change to my 30% Extra, I bind both RX's again.

It may not be required or it may be an inconvenient hassle, but I feel it's necessary. I do it for my own piece-o-mind. I honestly think 95% of the problems with these systems are operator error. I did it too. Almost cost me a plane. Whats it gonna hurt by binding it again? It's a hassle, but it won't hurt it.

I'm a bit tired to poke through all posts here, but what came to my mind is this: the signal from the antenna on 2.4ghz systems is projected out the side of the antenna, not directly out the top. One is never to point the antenna directly at the model as it will be in a 'blind spot' so-to-speak. The antenna is to be pointed straight up as one is generally not to fly a plane directly over his head. If the antenna was placed on the ground and pointed at the plane, the plane would be in a dead spot and lose signal, thus going into fail safe. I'm wondering if the radio being on the ground was deflecting signal off the ground and thus enlarging the dead spot. Anyway, that's my theory.

And yes, why on earth would you put down a radio to a running plane? Let's hope this is a lesson learned, and the OP and whoever else reading this thread never does this again.