Elevator Servos Out Of Synch
#1
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From: Point Pleasant,
NJ
9Zap I am using 2 elevator servos in the alievator mode. Both elevator servos work, but 1 seems little faster than the other a little out of synch. Adjusted servos arms and control rods identical.
Any Suggestions ?
Any Suggestions ?
#2

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From: Champaign, IL
Hi PlaneCrazzy,
Have you gone into a blank model and set up only Ailevator? If you do, do you still see this lag of one servo?
I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.
Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician
Also you may want to check our Website at (http://www.futaba-rc.com)
Have you gone into a blank model and set up only Ailevator? If you do, do you still see this lag of one servo?
I hope you find this information helpful. You can also reach our Futaba support technical team at 217-398-8970, or via fax at 217-398-7721.
Sincerely,
Krysta
Lead Futaba Customer Service and Programming Technician
Also you may want to check our Website at (http://www.futaba-rc.com)
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From: Point Pleasant,
NJ
Krysta,
I went to a vacant model and activated ailevator. Left elevator was out of trim. I went to sub trim to even out the control surfaces and found the elevators were still out of synch, left side was still lagging behind a little slower. I went to sub trim again and put the trim back to zero leaving the left elevator out of neutral, I then returned to ailevator and adjusted through there leaving the right side at 100% and adjusting the left side to 76%leaving both the left and right sides at neutral. I tested the movement and Wha- La !! They both move evenly in synch. Dont really understand why it did and how but the end result seems to be OK. Do you see any problem ?? Do you understand what happened ?
Thanks
Chris
I went to a vacant model and activated ailevator. Left elevator was out of trim. I went to sub trim to even out the control surfaces and found the elevators were still out of synch, left side was still lagging behind a little slower. I went to sub trim again and put the trim back to zero leaving the left elevator out of neutral, I then returned to ailevator and adjusted through there leaving the right side at 100% and adjusting the left side to 76%leaving both the left and right sides at neutral. I tested the movement and Wha- La !! They both move evenly in synch. Dont really understand why it did and how but the end result seems to be OK. Do you see any problem ?? Do you understand what happened ?
Thanks
Chris
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From: Strafford,
MO
Yes< I would like to see the response to this question, it seems to be a comon problem with Futaba My brother has a 9c and has same issue, I am going to buy a new radio and right now have not heard of this problem with the jr 9 chan.............
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From: , ITALY
Hello Chris,
when you set the subtrim you are actually moving the servo center. In other words, now the servo is closer to the end point. So the movement of the two servos is not the same, because one is closer to the end point than the other. So the speed will vary, too.
But even with a perfectly identical situation, one servo will move before the other. And this is not a futaba issue, even JR do that, simply because it is a design thing and can't be avoided.
Your TX sends the servo movements to the receiver in a sequential way. So the position are sent in this way: servo 1, servo2, ..., servo n. Given that it is a fact that if we want that servo 1 and servo n move togheter, we can't: there is a lag between the two.
The good news is that this lag is very small with modern equipements, in fact also in pattern airplanes two servo in the elevator are used with success. With earlier systems it was a problem actually in particular in hely setups, where more than two servos must move togeghter to have a straight flying!!!
when you set the subtrim you are actually moving the servo center. In other words, now the servo is closer to the end point. So the movement of the two servos is not the same, because one is closer to the end point than the other. So the speed will vary, too.
But even with a perfectly identical situation, one servo will move before the other. And this is not a futaba issue, even JR do that, simply because it is a design thing and can't be avoided.
Your TX sends the servo movements to the receiver in a sequential way. So the position are sent in this way: servo 1, servo2, ..., servo n. Given that it is a fact that if we want that servo 1 and servo n move togheter, we can't: there is a lag between the two.
The good news is that this lag is very small with modern equipements, in fact also in pattern airplanes two servo in the elevator are used with success. With earlier systems it was a problem actually in particular in hely setups, where more than two servos must move togeghter to have a straight flying!!!
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From: Champaign, IL
Our FAQ may help you understand this a little:
http://www.futaba-rc.com/faq/faq-8u-q594.html
When using a 2-servo function like Ailevator with digital servos, I notice a small lag in the response time of the second servo. How can I fix this?
Be sure the 2nd servo is not reversed in the servo reversing screen. This will increase this delay.
ALL radios show this lag (the 9Z is the industry leader in absolutely minimizing it), but it is so minute that only digital servos will make it readily noticeable. Please note that for all but the very VERY best precision flyers in the world, this lag will have no noticeable effect on your flying.
If you want to be completely free of this lag, you have just 2 choices:
Go to a y-harness (and an inline servo reverser if needed);
Utilize the 9Z WC2 transmitter, which has an accelerated frame rate around center stick for this very reason. The lag is so minimal with this radio that it literally requires instrumentation to measure the lag.
Krysta
http://www.futaba-rc.com/faq/faq-8u-q594.html
When using a 2-servo function like Ailevator with digital servos, I notice a small lag in the response time of the second servo. How can I fix this?
Be sure the 2nd servo is not reversed in the servo reversing screen. This will increase this delay.
ALL radios show this lag (the 9Z is the industry leader in absolutely minimizing it), but it is so minute that only digital servos will make it readily noticeable. Please note that for all but the very VERY best precision flyers in the world, this lag will have no noticeable effect on your flying.
If you want to be completely free of this lag, you have just 2 choices:
Go to a y-harness (and an inline servo reverser if needed);
Utilize the 9Z WC2 transmitter, which has an accelerated frame rate around center stick for this very reason. The lag is so minimal with this radio that it literally requires instrumentation to measure the lag.
Krysta
ORIGINAL: PlaneCrazzy
Krysta,
I went to a vacant model and activated ailevator. Left elevator was out of trim. I went to sub trim to even out the control surfaces and found the elevators were still out of synch, left side was still lagging behind a little slower. I went to sub trim again and put the trim back to zero leaving the left elevator out of neutral, I then returned to ailevator and adjusted through there leaving the right side at 100% and adjusting the left side to 76%leaving both the left and right sides at neutral. I tested the movement and Wha- La !! They both move evenly in synch. Dont really understand why it did and how but the end result seems to be OK. Do you see any problem ?? Do you understand what happened ?
Thanks
Chris
Krysta,
I went to a vacant model and activated ailevator. Left elevator was out of trim. I went to sub trim to even out the control surfaces and found the elevators were still out of synch, left side was still lagging behind a little slower. I went to sub trim again and put the trim back to zero leaving the left elevator out of neutral, I then returned to ailevator and adjusted through there leaving the right side at 100% and adjusting the left side to 76%leaving both the left and right sides at neutral. I tested the movement and Wha- La !! They both move evenly in synch. Dont really understand why it did and how but the end result seems to be OK. Do you see any problem ?? Do you understand what happened ?
Thanks
Chris



