Flap on VR-D to Elevator Mix on 9C
06-10-2013, 01:13 PM
#1
Flap on VR-D to Elevator Mix on 9C
Hopefully I can do this without making new linkages!
Plane is a Chipmunk with a Saito 100, not that it is all that relevant. Flaps are mechanically coupled to a single servo (linkage was installed when I got the plane) and I am using VR-D (the left slider) for control. Because of the way the linkage is set, full up flap is at 50 ATV and full down at -34. To do a mix, I am using Mix 1 with VR-D as master and Elev as slave. The elevator should be at neutral when the flaps are up and go to ~10% down when the flaps are lowered. However, with this mix on, I get 10% up elevator when the flaps are up, neutral when the flaps are about half way and 10% down with full flap. Yes, I could put some trim into the elevator to null this out, but then when I change the amount of down trim I need with flap, I would need to retrim the elevator. The mix does not show any offset. I went to the Futaba FAQ page but could not find anything to help.
Radio is a 9C. Suggestions?
While I'm at it, how much change does one click on the trim give? I was trying to use the number of clicks of down trim to see what % elevator I needed but realized I did not know the conversion. Thanks.
Plane is a Chipmunk with a Saito 100, not that it is all that relevant. Flaps are mechanically coupled to a single servo (linkage was installed when I got the plane) and I am using VR-D (the left slider) for control. Because of the way the linkage is set, full up flap is at 50 ATV and full down at -34. To do a mix, I am using Mix 1 with VR-D as master and Elev as slave. The elevator should be at neutral when the flaps are up and go to ~10% down when the flaps are lowered. However, with this mix on, I get 10% up elevator when the flaps are up, neutral when the flaps are about half way and 10% down with full flap. Yes, I could put some trim into the elevator to null this out, but then when I change the amount of down trim I need with flap, I would need to retrim the elevator. The mix does not show any offset. I went to the Futaba FAQ page but could not find anything to help.
Radio is a 9C. Suggestions?
While I'm at it, how much change does one click on the trim give? I was trying to use the number of clicks of down trim to see what % elevator I needed but realized I did not know the conversion. Thanks.
06-11-2013, 07:40 AM
#2
My Feedback: (11)
RE: Flap on VR-D to Elevator Mix on 9C
Use one of the point mixes to adjust the points where the flap affects the elevator travel. You have five points to work with, and so can set the location of each point when you move the slider.
There isn't a set number of degrees for the trim. Trim adjust about 10% of travel, though.
There isn't a set number of degrees for the trim. Trim adjust about 10% of travel, though.
06-11-2013, 10:22 AM
#5
RE: Flap on VR-D to Elevator Mix on 9C
Okay, it's working now but I'm not sure why! I selected AUX1 as the master on the 5-point curve and it works as it should with the first point at zero and the other points ramping up to 10%. This gives me the option of a non-linear down trim. I haven't tried AUX1 as master on a linear mix (just thought of it!) but will see how that works. However, I don't understand how VR-D controls AUX1. Hmm, but I did assign VR-D to channel 7 (where my flaps are connected since I use the Flaperon function for my ailerons on 1 and 6). And channel 7 is AUX1 (channel 6 is Flap). I guess that's it.
What percentage change does one click on the trim give? I was trying to use the number of clicks of down trim to see what % elevator I needed but realized I did not know the conversion.
What percentage change does one click on the trim give? I was trying to use the number of clicks of down trim to see what % elevator I needed but realized I did not know the conversion.
06-18-2013, 06:22 AM
#6
My Feedback: (11)
RE: Flap on VR-D to Elevator Mix on 9C
There isn't a specific number for percentage change per click of trim.
About the mixes, according to the manual, you can set VRA through VRE as "Master" in all of the mixes.
In your case, if VR(D) is controlling AUX1, and AUX1 is the master channel, then VR(D) will be the main control.
In the 9C manual, the programmable mix instructions do mention that you can use a VR as Master, whether linear or point mix.
About the mixes, according to the manual, you can set VRA through VRE as "Master" in all of the mixes.
In your case, if VR(D) is controlling AUX1, and AUX1 is the master channel, then VR(D) will be the main control.
In the 9C manual, the programmable mix instructions do mention that you can use a VR as Master, whether linear or point mix.
06-18-2013, 02:32 PM
#7
RE: Flap on VR-D to Elevator Mix on 9C
Bax,
The manual clearly states on Page 63 where the curve mixes are discussed that the master "can only be a channel. Cannot be OFFSET or dial."
So the reason it works is, as you noted, VR(D) is assigned to control channel 7 (AUX1) which I am using to control the flaps since I am running flaperons on 1 and 6.
I have to say these point mixes are handy as it appears I need 8% with just a little flap movement, 10% at the next point and the same for the rest of the movement.
Does the radio fit a smooth curve to the points or is it linear from one point to the next. More points would be nice I expect you'll respond by telling me to buy a new radio!
I see my 10C also has only 5 pt mixes.
The manual clearly states on Page 63 where the curve mixes are discussed that the master "can only be a channel. Cannot be OFFSET or dial."
So the reason it works is, as you noted, VR(D) is assigned to control channel 7 (AUX1) which I am using to control the flaps since I am running flaperons on 1 and 6.
I have to say these point mixes are handy as it appears I need 8% with just a little flap movement, 10% at the next point and the same for the rest of the movement.
Does the radio fit a smooth curve to the points or is it linear from one point to the next. More points would be nice I expect you'll respond by telling me to buy a new radio!
I see my 10C also has only 5 pt mixes.
06-19-2013, 06:44 AM
#8
My Feedback: (11)
RE: Flap on VR-D to Elevator Mix on 9C
Right, the curve mixers cannot use offset or dial for the master; the linear mixes can.
The points are just that, fixed points. Operation would be linear when moving between the points.
If you need more mix points, you will need "more transmitter". The 12FG, 12Z, 14MZ, and 18MZ all offer up to 17 points in their mix curves.
The points are just that, fixed points. Operation would be linear when moving between the points.
If you need more mix points, you will need "more transmitter". The 12FG, 12Z, 14MZ, and 18MZ all offer up to 17 points in their mix curves.
