ar700 advice

[whittm]

Hi there everyone. Some of you may remember my previous thread. I had the situation where I had finished setting up my heli (a jr airskipper/vibe 90, with ar7000 receiver and gp750 gyro).

I then was recommended that a governor would be essential really. At that point I decided to go with an ar7100r with integrated rpm governor. I've now soldered ec3 connectors to the battery and charging leads, charged the battery and temporarily wired up the receiver to the servos.

I bound the receiver to my dx7 transmitter and tried the controls. I'm a bit gutted as all my settings seem to have been obliterated :-(

My first question is, is this normal I. e for two different receivers to interpret the signal from the same transmitter differently?

Also, it's not just slightly out, the servo centering is 3-4 degrees out at mid stick and travel it was 12 degrees both ways and is only about 5 degrees negative and 7 degrees positive. The throttle is reversed and has some sort of strange movement, I think it looks like it has a lot of expo in it, it moves very little mid stick and is very sensitive at high stick and not so much in low stick.

I'm about to reset the sub trims and travels and also the swash and other mixes. Then check the links for length and then setup again. But before I do that, thought I'd ask opinions on here as to whether they think there may be something wrong with the receiver?

(Please excuse the title, auto correct on my phone taking over again!)

[Granpappy]

I'm not a Spektrum user but I did read that the ar7000 rx is 1024 step whilst the ar7100r is 2048 step and that the DX7 cannot resolve 2048 step receivers. So I would hazard a guess as to this being the reason that the servo positions have changed with the new receiver. Perhaps someone else could clarify this.

[whittm]

Ok, thanks for that! I had a second look at the receiver and realised that I had plugged the throttle servo(a ds821) in to the unregulated voltage side. I've now swapped it in to the regulated side and it's now as smooth as when it's plugged in to the ar7000. Still a little slow to react. ..It looks like it's sticking at points.

Anyway, got that problem sorted, just want a few more opinions on whether I should just reset and setup again?

[waveydavey]

I don't know the Rx and if it is a different resolution to what you had then it could be responsible. I would spend the few hours and do the reset, or I've got a throttle jockey that you can have and using the backplate sensor you've got you can go back to the original Rx

[whittm]

Thanks wavey davey, although, I've now sorted it by the look of it. I really don't know what exactly happened or how, but I've scratched my head over it for the last two days.

An hour ago I decided to swap my old receiver back on to the heli. I was truly amazed and shocked! The same problem as with the other receiver, the head was all over the place!

Then I began to dig. Luckily, I took photos of the transmitter screen showing travels and sub trims after I had set the heli up! . ..I compared them to the current settings. They were all wildly out! 20 points out on aileron sub trim! I reset all the figures to the photos. ..The head was spot on, once again!
I then plugged in the ar7100r...yet again, the head was bang on. ..pheeeeew! Now the only explanation I can think of, is my 3 1/2 year old daughter. Only problem is. ..I can't explain how on earth she could have gotten in to the settings menu. ..she's also pretty good when I tell her not to touch my stuff! The only thing I think might have happened, is that whilst I was in the garage, she was messing around with the sub trim buttons!

[Grumpy]

Looks like you solved it. For sure the receiver resolution wouldn't have been the cause because the receiver will only work at 2048 resolution if the transmitter it binds with supports it, otherwise it just works at 1024.