I can't get "Auto Trim to work on Helicommand with x9303 radio

[Navigator53]

I changed Rec'vr from 72 hz over to R921 Rec'vr on x9303 radio.

Elec Heli flys great but could use a little auto trim.

I've gone back thru the binding process.

Auto trim is on Gear channel with grey wire plugged into "Gear" on Rec'vr

Tried reversing switch from normal to reverse in that menu on radio.... nothing

Tried reversing grey wire in Rec'vr then the bar graph in pc program doesn't change.

Tried the throttle from 0 to full while flipping the switch.

Auto trim works in the pc program but doesn't give me a red light on HC module or change trim settings, they stay at 0.

I've tried multiple end points on gear channel endpoints, but still no trigger.

Gear switch is assigned to gear channel in the "Device Select" radio menu.

Auto trim "inhibit" remains checked all the time.

No mixes in the radio.

What am I missing Guys?

Mel

[pril250]

Hi

Not 100% familiar with the 9303, does it have a monitor function in the menu and if so what happens when you toggle Gear switch. On HC (I only know FM-no autotrim) does autotrim require a positive or negative value (ATV) to operate.

[Trooper]

Hi Mel,
Autotrim requires a signal greater than 60% to trigger. However there is also an Autotrim Inhibit to prevent you from using AT whilst on the ground. The value that removes the inhibit is the Pitch Minimum setting on the RC&Trim tab.
Normally as you raise the collective above pitch minimum the inhibit check mark should go and if you then momentarily activate AT it will write the values to the RC&Trim AT settings.
You can see the actions of AT on the Diag tab.
I use a Futaba and the Trainer momementary switch, my AT value is set at 65%.

Ian

You have selected 'AT only' or 'Gyro Mode and AT' on the Gyro tab?

[Ivor Hill]

Hi Mel, cant help much like Trooper I use futaba and also use the trainer switch. I use an external gyro so I have the grey wire connected to channel 8 and trainer switch programmed to channel 8. Two points'if memory serves me right.
The auto trim function wil be seen as working in the software even if it is inhibited.
If you have autotrim switch only or autotrim and gyro mode selected under the tail gyro tab then the bar for aux channel under the diagnose tab should not be all the way right as yours is. It would only normaly be over there if autotrim is actvated.
It looks like you have two problems. The gain value for autotrim has a + value when off and be should be a - value for off and a + value of 65 or more to acivate it.
The second problem is that auto trim is inhibited and the coll bar shows that you are at about 60% pitch so it should not be inhibited but under the trim tab it shows -49 which means it would be inhibited ?.
Just a thought have you pressed the set button ?. One previous post indicated that when HC is set up for autotrim if the set button is pressed it can inhibit the autotrim function and if this is true the only way I can see to correct this would be to go though the learning set up again. I cannot confirm this because I have never pressed the set button.Like I said just a thought. Hope this helps good luck. Ivor

[Trooper]

Originally Posted by Ivor Hill

The auto trim function wil be seen as working in the software even if it is inhibited.

This is right 'AT Request' check will activate when you select AT even if the Inhibit is still checked. You can set the required value - anywhere between 60% to 100%.

Originally Posted by Ivor Hill

If you have autotrim switch only or autotrim and gyro mode selected under the tail gyro tab then the bar for aux channel under the diagnose tab should not be all the way right as yours is. It would only normaly be over there if autotrim is actvated.

I assummed it was all the way over because Mel had selected AT, however on looking closer I can seethat 'AT Request' is not active.

Originally Posted by Ivor Hill

It looks like you have two problems. The gain value for autotrim has a + value when off and be should be a - value for off and a + value of 65 or more to acivate it.

If you don't want it to switch out of HH then when AT is off it should be 0 and when active a value of 60 or more. So it looks like you need to reverse your gear channel settings.

Originally Posted by Ivor Hill

The second problem is that auto trim is inhibited and the coll bar shows that you are at about 60% pitch so it should not be inhibited but under the trim tab it shows -49 which means it would be inhibited ?.

I believe the setting of -49 Pitch Min on the RC&Trim tab means that the Inhibit will be removed at a lower setting of the Coll Pitch. (The default value is 30).
There is a way to change this value manually - you'll have to PM me for the solution.

Originally Posted by Ivor Hill

Just a thought have you pressed the set button ?. One previous post indicated that when HC is set up for autotrim if the set button is pressed it can inhibit the autotrim function and if this is true the only way I can see to correct this would be to go though the learning set up again. I cannot confirm this because I have never pressed the set button.

I used the Set Button on my initial set up and whilst I was fine tuning the internal gyro setting, it did not inhibit the AT function for me.

Ian

[Navigator53]

Thanks Ian, Ivor & Pril,

I forgot to mention that I'm not using the HC internal gyro so tail function is external with a 401 and that part is working well.

I did a carbon copy of settings going from an xp9303 (72) over to an x9303 (2.4) and autotrim worked well before so it must be in my programming in the software.

I did the red reset to start, forgot to tell it single servo on collective on the radio after aile/elev/collective were waaaaaaay off.

After that I started over, teaching it stick positions and it holds hover position decent, but needs a little auto trim.

I'll do what you guys said and go back over it again tonight.

Thanks guys!

Mel

[Trooper]

Sounds like you need to reverse your Gear channel then.

Ian

[Navigator53]

OK, making progress here:

Selected "Auto trim switch only" under the Tail Gyro tab.

Now I'm getting AT to check, but not AT inhibit to un-check not matter how high I put the throttle.

Pitch minimum remains at -49 in the RC & trim tab.

Should I go thru the set button procedure, start over and re-teach stick travel?

Mel

[Navigator53]

Gotta Love our Friends/Guru's accross the pond

Being elec. I had throttle curve not linear, made it linear

Went thru the factory reset, set up, stick travel thingy again.

Now it's working even though I have Pitch minimum at 50 this time.

Is it ok to add expo now? Dual rates?

Forgot to answer your question Pril, yes it has a monitor function but it was showing the gear switch travel just fine, but without getting the inhibit trim to uncheck, it wouldn't auto trim.

Ian, I'll post all the screen shots you've asked for once it's flown then pm you that they're on my profile.

Thanks again guys!!

Mel

[pril250]

It is OK Mel, by now I too have learnt a few new things about HC setup

[Trooper]

Ah the old linear curves problem!! Glad to hear you sorted it.
The Pitch min value doesn't seem to make too much difference - I have seen some that are very negative but you don't want it too much positive.
Now you can add expo etc once its working. And don't forget to re-set your curves!

Ian

[Navigator53]

Heli is dancing on me in Position mode even a few meters above the ground so I reduced position gain from 8 to 6.

Holds smooth in horizontal mode.

Haven't had a chance to try it yet, but did I do good?

Thanks guys,

Mel

[Trooper]

You need to reduce the Pilot Gain for Position mode to stop it dancing around, rather than the overall gain.

Ian

[Navigator53]

Ooooops...

Back to the ol' pc

Thanks Ian!

Mel