Dual rates and travel adjust

[alistair.howie]

Can I just check my understanding of this?

Travel adjust = ATV = end point adjustment = the absolute limit of servo movement i.e. can't be overridden by any other TX settings

Dual rates set a limit WITHIN the end points. So 60% dual rate when ATV = 125% means maximum servo movement of .6*125 = 75% ... which of course I could achieve by not using D/R and just setting my end points to 75%.

Is all that right? I'm just trying to make sure I full understand the recommended settings of my new mCPX.

Many thanks.

[chugga-bug]

Yep, that's right.

[steve_b]

Dual rates set a limit WITHIN the end points. So 60% dual rate when ATV = 125% means maximum servo movement of .6*125 = 75% ... which of course I could achieve by not using D/R and just setting my end points to 75%.

The advantage of using dual rates is that you can effectively have multiple end points set depending on what idle up setting you're using, so you can end up having the heli really docile on one setting then really responsive on another setting, which you can't do just using end points alone.

[unwind-protect]

Your general method is correct, but the ATV is really just another scaling factor. With an ATV of 100%, the servo can be moved past that 100% point, say by using a dual rate greater than 100%, or a programmable mix targeting that channel.

[alistair.howie]

Thanks all - so just a follow-up question then. In my DX8, I have ATV set to 100% across the channels, but when I go into aileron or elevator for example, my curve does not start at 0% nor end at 100% ... perhaps 15% and 85% or thereabouts. I've put in some dual rates and I can see my curve flattening out or getting steeper as I click through the DR switch, so that is working.

But why don't these curves start and end at 0% and 100% when ATV is set to 100%?

[Mslater]

Just a note, on some Futaba sets the End Point have two settings Travel Adjust and Servo Limit.

[Mslater]

But why don't these curves start and end at 0% and 100% when ATV is set to 100%?

I know little about the DX8 setup BUT on a Futaba the max ATV is 135%. To get 0 and 100 I suspect you'll need to set the MAX ATV possible - it will certainly go higher than 100%