DX7 - AR7000 Complete Signal Loss

[fredmillard]

Greetings folks:

While hovering my TRex 450SA, I had a momentary loss of all signal between my DX7 and AR7000 reciever resulting in a crash from about 15 feet above the deck.

Does anyone know of others experiencing a similiar issue, and if so, what if anything can be done about it to avoid a similiar mishap in the furture?

Thanks Fred

[Tom Fiddler]

Tell us more of exactly what happened.
Did your failsafe settings kick in?
Did the motor shutoff?
Stuff like that.

[fredmillard]

I am not sure, I am relatively new at this. All I can say is that I was hovering about 15-feet off the ground when all of a sudden the bird completely stopped responding. I had no cotrol over it for a couple of seconds. Being inexperienced i was unable to recover resulting in it falling to the ground. Fm

[Danal Estes]

What battery, motor, ESC, BEC?

[Eyefly]

I had the exact same thing happen to me. But I was using a JR 9303 and a 770 rx. Turns out it was the ESC doing goofy things. My point is that you can not be too quick to blame the radio system. Please list your set-up to correctly diagnose the cause. It could have easily been the speed controller or the BEC which caused this to happen.

Alex

[WillJames]

I have seen absolutely nothing to make me think it was the radio, sounds more like a power failure on the heli or something. There are a LOT of people flying the DX7's and none have had a confirmed RF issue from what I have seen.

Check your heli very closely becuause it is very likely you have some other issue liek the power lead coming out of the RX or something like that.

After the crash were the red link LED's on on your RX(s)?

[cdrking]

How does one tell the difference between a radio lockout problem and a ESC, BEC issue?

Jeff

[DavidH]

Going to play Devils Advocate a little.
It is amusing to me. If this was any other modulation but 2.4 ghz. There would be posts telling you it was a radio problem. Yes 2.4 is new technology and is SUPPOSE to be bullet proof. But I hope everyone that uses the new technology doesn't go with the mentality that nothing will ever happen.
With electrics, there is all kinds of RF being emitted from the electronics. So check and make sure that the ESC, BEC and etc. etc. are working as they should.

Make sure your throttle fail safe is set to very low speed or off position when fail safe is activated also.


David

[Jermo]

Fred what happened to the motor? did it speed up or slow down? stay the same? did the servo's just not respond or did they move? which reciever do you have? is it the stock DX7 RX? (AR7000).

I was video taping my DX7 last night and had simular indication where the servo's just stopped responding. Both RX lights were solid, I found that my flight pack battery was almost dead (I use that instead of lipo on the ESC). That begs another question, what ESC/BEC are you running and are you using a single battery or battery for rx and battery for motor.

If you can post pictures of your component layout that would really help..especially ESC position, wire routing..etc..
Jermo

David - I definately agree that the radio gear can't be ruled out yet but you have to admit it's pretty solid compared to anything else out there (barring other 2.4GHz systems).
Jermo

[SteveL]

I think it locked out :D
Sorry I could not resist.
The motor should have stopped either way.

[Jermo]

I think it locked out :D
Sorry I could not resist.
The motor should have stopped either way.

I'm sorry, insufficient information to accurately speculate. A Lockout on the DX7 will result in the throttle going to the position it was in during binding (with the AR7000 and AR6000). If you have an AR6100 reciever all channels will go to their binding position upon lockout.

I think it would be natural to bind the radio with the throttle all the way down but we really don't know all the details. It's possible but :dontknow


Jermo

[WillJames]

SteveL wrote:
I think it locked out
Sorry I could not resist.
The motor should have stopped either way.


I'm sorry, insufficient information to accurately speculate. A Lockout on the DX7 will result in the throttle going to the position it was in during binding (with the AR7000 and AR6000). If you have an AR6100 reciever all channels will go to their binding position upon lockout.

I think it would be natural to bind the radio with the throttle all the way down but we really don't know all the details. It's possible but


Jermo



That is an inside joke from Clint's Birthday Party Event Jermo that Steve is referring to.

[Jermo]

hehe...ok ;) sorry I missed it.. just a bit far to drive .. maybe next year !! :D

troubleshooting via forum is difficult sometimes but I enjoy the challenge.
Jermo

[fredmillard]

Shouls I post photos, and if so, of what? I really hope that I am mistaken, but I feel pretty confident that it was not pilot error, rather a lockout. PS thanks so much to everyone for all the feedback and comments. FM

[cdrking]

Fred,

There is an excellent electric RC heli guy down in Vancouver, WA. He can probably help you look over your machine. His name is Russ, he is a member here but I haven't "seen" him on here lately.

Let me know and I can dig up his info.

Hope to see you at some of the NW fun flys.

Jeff

[Jermo]

Please post pictures that show wire routing from/to the ESC, Reciever, and motor. These will probably show where the components are.
Jermo

[fredmillard]

Hi folks:

Here is what I decided: I installed a Quark Pro BEC 3, deactivating the BEC integrated into my Align ESC. Although I have yet to take the 450 out for a serious test-flight (wind and rain), I am fairly confident that this may resolve the lockout issue I experienced. I will certainly keep everyone posted.

Many thanks to everyone for their much-appreciated input, comments, and feedback. Fred

[Jermo]

Don't count out component placement. Having the RX close to the motor/wires and/or the ESC can still potentially cause problems for any electronic equipment. 2.4GHz systems are nice to prevent being shot down but they don't overcome the limits of component placment. Motors and controllers have strong electric fields and can potentially affect any electronic system.
Jermo

[madclown]

I just had the same thing happen to me. I was about 100' out and about 50' high. The tx and rx lost connection. Needless to say the heli came to the groud fast. I repaired the heli and started trying to replicate the problem. Found that when i cycled the "gear" switch the tx and rx lost connection for 3-5 sec (both lights on the two rx went out and all control was lost). Also sometimes when operating the fight switch from normal to idl 1 it would do the same thing. So I took it in to the LHS where they have good service. The owner was very helpful. We first tried a diff. tx with my rx. With this new tx the problem went away. We then tried my tx with a diff rx and the problem was there. We concluded that the problem is in the tx. The LHS guy then called horizon who said they would replace it. The problem for me is that he will not have another heli DX7 until next week. I hope this helps you.