throttle curve issue

[slammers]

There seems to be a strange issue with throttle curves. For my scale models I setup a throttle curve in idle1 with a straight line at 50% output from low stick to mid stick and then a linear line from 50% to 100% from mid stick to full. You do this by setting rate A to 0 and rate b to 100. If you do this and then bring the throttle to the bottom, you can effect the throttle opening by trim.

I do not feel this should happen. On the 9zap setting trim mode to ATL would only effect the trim at the bottom end of the travel and this was controlled by servo output. On the 14MZ ATL does the same thing but its dependent on STICK position.

Put another way, on the 9zap if you have a throttle curve that would only close the throttle to 30% opening the trim would never effect the servo position because it was moved above a value where the trim would have any control. On the 14 it seems the curve has no bearing on when the atl will disable trim control and simply looks at stick position.

Can anyone else confirm this behavior?

Shawn

[bob00]

Yes! Wasn't sure if this was the Futaba way of doing things - my last readio was a 10x. A few of us have noticed the following minor things w/ the 14 and have found workarounds in most cases.

- because the throttle trim seems to work by stick position vs. servo (output) position, low stick w/ a standard "V" curve is affected. Push the stick all the way down and then move the T3 trim and observe on the servo monitor - the servo position changes.
* WORKAROUND - disable trim for all but NORMAL mode using the FUNCTION screen

- if using J3 (throttle stick) to control the timer on/off, the timer will switch off if the stick is pulled to full -ve even with a "V" curve, stopping the timer for the duration spent at near full -ve collective.
* WORKAROUND - none really, just make the OFF range on the stick very, very short (2 - 4%)

- cyclic throttle mix can overdrive the throttle servo (or esc channel). This one is strange 'cause it appears to work. Dial say 40% cyclic-thro mix on AILE and ELEV. Watch using SERVO MONITOR. Move the throttle to 100% and give a cyclic deflection - the expected behavior is observed, the throttle isn't pushed past its TRAVEL limit. Now slowly move the throttle to center stick - as the stick moves away from wide open the throttle is driven past its set TRAVEL limit.
* WORKAROUND - using ATV, set the LIMIT to match the TRAVEL setting.

- Rob