Author Topic: Jr xbus servo  (Read 1833 times)

Offline Mike rieder

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Jr xbus servo
« on: 15, April 2017, 08:20:17 AM »
I have two nx xbus servos on my sebart mythos elevators, one is not reacting for the first 2-3mm of travel compared to the other one, which isnt great! It looks like you can set the dead band on these with a JR tx (I run multiplex tx etc). Does anyone know if i can setup the servos with a jp propo xb1-cpg servo id programer?
And if so, a cheaky request has anyone got one i could borrow in the Suffolk area?

Offline Mike Wood

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Re: Jr xbus servo
« Reply #1 on: 18, April 2017, 02:28:19 PM »
When I've investigated some of the settings that can be set on Futaba servos, I believe the initial settings
are what the manufacturer thinks are the best initial settings for the servo, for the type of use that servo
is aimed at e.g. Car, Helicopter, Fixed Wing Plane.

So for instance, the dead band on car servos can be seen to be set smaller than on servos aimed at planes,
which is done to take into account the different environment the servo sees and each is appropriate to
ensure the servo reaches the desired position but stop the servo overshooting. Car servos will see greater friction in moving controls, while
say plane servos will see less friction and with large control surfaces have more opportunity to overshoot due to the
inertia of the control surface.

I'm thinking that both servos you have should perform in an identical manner out of the box and no changes
to the initial settings required.

What one doesn't want is a servo continually oscillating to find it's correct position and the settings to achieve this can vary, as mentioned above,
depending on if it is used in a car or plane etc.

Also, some Futaba transmitters can program their S.Bus servos, so it's possible it can be done from your transmitter, however
as mentioned above, I would expect them perform identically out of the box.

One more thought is that there may be some mixing or other setting on the transmitter that is set, that means
the servo is just doing what it is being told to do. One could try swapping the elevator leads around and see if the
the differing response transfers to the other servo.

One could also put the servo, disconnected from the control surface on a servo cycle either from your transmitter or
a stand alone device and check that the servo cycles as expected.

One could also use the Servo Monitor function on your transmitter (if it has one) to watch the output that is being
sent to the servos as you move the sticks or change switch positions.

« Last Edit: 18, April 2017, 02:52:47 PM by Mike Wood »

Offline Mike rieder

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Re: Jr xbus servo
« Reply #2 on: 18, April 2017, 08:21:14 PM »
Thanks Mike, yes i am thinking it could be a duff servo as as you say you would have thought both would be originally programmed the same.
Yes i have tried swapping the wires to see if it is the tx but it did the same.
Good shout re removing them and trying it on a servo tester without being connected as this should give me a definitive answer.
I will try this then pos just replace it, and hope it is better, but at £60 odd a pop i bit miffed.