servos never go to the previous position

  • Hi,

    i have a Competition SRS with 2x futaba R6303SB, servos S9177SV

    when I turn on the system the servos never go to the previous position. They move a few millimeters down or up.

    What could be the cause? How can I solve the problem?

    Thanks you


  • I only did 5 flights with this plane using the low excursions condition for the imac flight and for the initial model setup.

    The problem is that when I turn on the Competition srs I must, always, to adjust the servos mechanically to align the moving parts to the fixed parts because they always change position by about 1/2mm

    This problem occurs on all S9177SV servos but especially on those of the elevator.

    I have n.6 servos Futaba S9177SV for aileron and elevator, n.1 Futaba A700 for rudder, n.1 S3072HV for throttle all powered at 7.4V

    Radio Futaba T12FG Setup is:

    End Point: 135%

    Sub Trim: 0

    N.3 Flights Condition (low/med/high)

    2x Futaba R6303SB receivers set to normal mode

    All installed equipment is new.

    I gave you as much information as possible, if you need more, you let me know.

    thanks you


  • Hello,

    I read another user with the same problem as me in this post:

    Trim instability issue with PB Competition SRS

    I did the following tests:

    1) set the R6303SB receivers to normal mode and high speed.... failed

    2) set the outputs voltage to 5,9V..... failed

    3) set the elevator in the synchronized outputs channels C and D.... failed

    4) I connected the elevator servos directly to the receiver R6014FS with powered at 4,8V .....ok, works well

    I hope these tests can help you understand the problem

    I'm waiting for your feedback

    thanks you


  • Hi,

    I exposed the problem of PB to technical support of Jonathan italy because I bought it from them with invoice and guarantee.

    They sent their courier to take the package with the PB on 22 October 2019.

    A month has passed, they told me they sent it to the manufacturer, but they don't tell me when I can get it back and that's why I ask you for information.

    if you have this PB with serial n.279345 under repair, can you give me information, please?

    - What kind of problem did you encounter?

    - It is normal that I have to use a repaired PB on a new and very expensive model? I've never used it in other models

    - when will this problem be solved?

    tell me what to do

    I thank you in advance and wait for your feedback


  • What says the sheet - did you add an error describtion to your parcel? You must understand that the people who repair the PowerBoxes do not look in the forum and check which anonymous post belongs to what Powerbox coming in to repair...