Where is the real centre point?

[GizmoB73]

This may be a silly question, but I am going to ask it anyway.

On my Dx7, when my throttle/pitch stick is pysically in the mid position, the positions shown on the digital display are not centred. The difference might be nearly 2mm at the scale on the stick, which is not small.

I recently noticed this when resetting my pitch and throttle curves.

Is this a calibration issue somewhere? should I worry about it, or just put up with it?

Cheers

Gary.

[chugga-bug]

On the Pitch or Throttle menus, check where you getting 50%.

There was a thread about recalibrating the DX7 a while ago.. Someone may be able to find it for you.

[GizmoB73]

On the Pitch or Throttle menus, check where you getting 50%.

There was a thread about recalibrating the DX7 a while ago.. Someone may be able to find it for you.

That is what I was referring to, the electronic centre point doesn't agree with the physical centre point.

I wasn't really sure what to search for. I will try again, but any pointers appreciated.

Thanks.

[chugga-bug]

Found it... http://www.rcgroups.com/forums/showthread.php?t=609802

[chugga-bug]

Also read this;

http://www.rcheliaddict.co.uk/showth...5986#post75986

(ignore my post. I was talking out my ar@e!)

[GizmoB73]

This forum really is the best.

I have re-calibrated my DX7 through the service menu now and it is spot on. Now I can get my swash and pitch set up properly on my heli.

Thanks

Gary.

[moyesboy]

I've not followed those links and looked in the service menu on the dx7, but there may well be a more simple explanation to your problem.
Are you in normal mode when you see this problem?
On the transmitter there are two switches left and right of centre at the top. One of these is the rather awkward buddy box switch when its active. However in normal mode they set hover trim and hover pitch.
Due to an annoying oversight by horizon it is impossible to disable these, but they only operate in normal mode.
Their function is only of interest to people who obsessively hover in normal mode and want the stick always in the same place whetever the weather. They are a right pain for us normal people and it would be better if they had never been invented.

If you go into the throttle or pitch curve in normal mode and look at the mid point you will see that at the top the percentage is dispayed when you line up the sitch line with the middle. At this point if you move the throttle/pitch hover trim switch the middle point is moved and the percent changes (and becomes different to thre curve percentage number). It only has effect arround centre stick. You have to make sure there is no hover trim offset for throttle and pitch.

When this is corrected then all the channel displays should line up at centre stick.

If anyone on here has found out how to disable hover trims then let us know! The switches have no other fnction (except buddy box). Its quite tempting to superglue them.
Other manufacturers did the same thing, I had an optic 6 that had levers on the side for this and they were always getting knocked so I had to tape over them. It'd be so much more useful if these switches could tweak the gyro gain or something like that but they are not assignable at all in the software.

Hope you haven't done some sort of recalibration to counteract hover trims and then found you have put the throttle/pitch curves off in flight mode 1 and 2!

My Dx7 seems to be spot on, apart from when I had some hover trim set by mistake.

[GizmoB73]

I actually double checked by selecting a completely new (empty) model and checking the input values when the throttle stick was centred on the gimbal. They were also incorrect (in axactly the same way) on the new model so I was happy that it wasn't any of my settings that had caused this.

I have never really used those hover pitch and hover throttle switches as I didn't really see the point of them either.

Thanks anyway for the suggestion.

Gary.

[HiroboFreak]

If you're getting 100% travel with the stick at the top & -100% travel with the stick at the bottom, who cares if the centre mark on the gimbal isn't exact?

It's not like you look at it when you're flying.

[LaurenceGough]

But the fact is it should be at centre in the middle of the stick travel.

Mine was out about a mm but I recalibrated it spot on. I think it flies much better now. I think they should calibrate it well at the factory though.

[GizmoB73]

If you're getting 100% travel with the stick at the top & -100% travel with the stick at the bottom, who cares if the centre mark on the gimbal isn't exact?

It's not like you look at it when you're flying.

For me, i found it confusing when setting the swash level and then when setting my pitch up. i.e. if I want zero pitch at mid stick i have to take into account the gimbal error because physical mid stick was about 53 instead of 50. This was making just under 2 degrees of error in the pitch.

I think it is much simpler to just calibrate the tx so that it is where it should be. Then everything can be setup spot on.

[jboweruk]

You know, I'm really beginning to have my doubts about Spektrum TX's, I know the Blade series is from Horizon too and they seem to be decent helis, but from reading this and my troubles with the DX6i I'm having serious doubts about whether a more expensive TX like the DX7 will serve me any better.... Also the one for my CX2 (the orginal tx) had issues after a while in use.

[HiroboFreak]

For me, i found it confusing when setting the swash level and then when setting my pitch up. i.e. if I want zero pitch at mid stick i have to take into account the gimbal error because physical mid stick was about 53 instead of 50. This was making just under 2 degrees of error in the pitch.

I think it is much simpler to just calibrate the tx so that it is where it should be. Then everything can be setup spot on.

Easy..... Go into your pitch curve menu & make sure your output is 50%

Even easier..... Set your pitch curve to 0 - 50 - 50 - 50 - 100 during setup.

[LaurenceGough]

You know, I'm really beginning to have my doubts about Spektrum TX's, I know the Blade series is from Horizon too and they seem to be decent helis, but from reading this and my troubles with the DX6i I'm having serious doubts about whether a more expensive TX like the DX7 will serve me any better.... Also the one for my CX2 (the orginal tx) had issues after a while in use.

DX7 is great, no problems whatsoever. And what I've used of the DX6i I've been impressed about it, although not as nice as the DX7 it's still the best for the money vs features.

Nothing wrong with either, Spektrum/JR radios are easily the best IMO!

[jboweruk]

Must just be rotten luck on my part then, not inspiring confidence in me having a better heli though.....