Vbar Neo T-rex 250 after setup (collective and cyclic angle)problem

Hello, I have mounted a vbar Neo vlink express and updated it to PRO on my t-rex 250. The problem is that when I have adjusted everything and finally get 11,5 deg on collective and 8deg on cyclic and exit the setup meny(doesent mather if its on pc or vbar control) the swash collective and cyclic range is like 17 and 9 degrees.
I cant understand why this happens when its perfect in setup mode.

I cant seem to find any setup advice in the forum, have anyone made this happend or is the t-rex 250 not compatible with vbar ?



1 mal bearbeitet. Zuletzt am 27.03.2022 22:48 von Nicolai-1988.

Hi,

this is normal _if_ you were using Lightness (nicknamed Anti Gravity).
This parameter shifts the collective pitch curve, to make the model feel lighter. In flight, it is additionally fed by the accelerometers.

Dial down Lightness to zero and you see (approximately, control loop still active) what you set up before.

I am sure Lightness will help the 250 to fly even better, but you must make sure that you get no binding on servos, linkages, on the swash plate, with the shifted collective pitch range (both pos. and neg., flip model to see the effect when inverted).

—Eddi

Born to fly ...
forced to work.

Hi, same thing happened here with a Logo 550SX and a Logo 700 (using Spektrum Satellites) after adjusted Collective (+14, -14) exiting setup, collective throws changed to -10, +16. Ther is no Lightness/Antigravity on the Neo Vbar non Vlink computer software, Neos are updated to latest version.

Need to play by trial & error on the setup with collective throw, to get the right collective throw after exiting setup, it can be done, but it does not feels right, that did not happened with 3 more Helis with Neo Vbar non Vlink same Spektrum Satellite configuration (2 Oxy 4 Max and a Goblin Buddy 380).

Any help will be appreciated

Hi,

Lightness is a Pro Parameter.

On some VBar NEOs, the memory for this parameter seems to be pre-set with a value of 35, which shouldn't be there, since in Express, you can not change it, you can not zero it out.

But you can exploit a shortcoming in the computer software:

. open VBar NEO Setup Software, _without_ a VBar NEO connected.
. you will see the Pro user interface, with the expert parameters, doctor's hats
. open the Mainrotor Expert, you see Lightness
. _only now_ connect your VBar NEO, and also have it connected to your VBar Control
. the software will detect it's Express, but the Mainrotor Expert will remain open
. now you very likely see the Lightness value change to 35
. zero it out
. switch banks on your radio, and zero out Lightness on the other two banks
. job done

On a sidenote: you can not change other Expert parameters, they will always be reset to default. It's not like you can 'Pro' your VBar NEO this way
And, adjusting for the offset by adjusting the overall collective is not a good idea ... inverted, everything can be different

Kind regards

Eddi

Born to fly ...
forced to work.

Hi Eddi,

Thanks for the reply, in my case on all my Vbar Neos I do have, they are Version 6.3.1 Pro+Rescue, still at the Main Rotor Expert Parameters there is no Lightness Option, I have played still most of the options at the expert options (mainly Collective Balance & Cyclic Optimizer) and there is no change after setting Collective throw, when I exit setup the collective is changed approximately +3 degrees. Below the options of Main Rotor expert.
Other way I found to compensate instead of the overall collective, is in the Trim of swatch plate, after leveling it, leaving the blades at -3 instead of 0, but again it can backfire and does not feels ok.

Parameter & Options shown:
10 Elevator Precompensation
10 Paddle Simulation
50 Heli Size
60 Integral
0 Pitch pump
10 Expo
27 Collective Balance

45 ? Cyclic Optimizer

Thanks

Hi,

then, you still have an older version of VBar Control Manager and VBar Setup on your computer.

See here for a patch.

Or uninstall, delete the program folder for good measure, download again from here, install again.

Kind regards

Eddi

Born to fly ...
forced to work.

Thanks Eddi,

Patch installed (Mac OS), it worked, I can see Lightness now and zeroed out on all banks, now the throw of the Collective works after exit setup (a minimum 0.3 degrees difference).

Thanks a lot for your help, congrats on our experience.

Sincerely

Victor