Movements on surfaces when I Power on PB Royal SRS

  • Hi Richard,

    I have a problem. I just installed the Powerbox Royal SRS on my large SM Viper. When I turn on the Powerbox I see some movements in some of the surfaces such as elevators and rudders. Some of the movements are sometime small and other times quite large almost to the point of linkage binding. This only happen for a fraction of a second, then all surfaces to neutral position and everything is working OK. The behavior is completely random. I am using as a radio a DX 18 and this had never happened with the previous Powerbox Royal Spektrum I used to have on this plane, neither with all my other Spektrum receivers.

    I bind the radio to the Powerbox on a precise position (neutral all my surfaces) and I have those positions maps on hold. I tried FS too instead of Hold and using the FS learns position memory and the behavior is the same when I turn on the system.
    Other than that everything is working perfect after a few seconds has pass. I am worry to try to setup my wings as this behavior might damage the flaps on my Viper.

    I do believe I have the latest v4 version installed on my Powerbox Royal SRS.

    Let me know your thoughts, I have another Powerbox Royal SRS to be install on my A10 but I need to solve this issue ASAP.



  • Hello,

    We found that some servo types are doing that, the problem increases with 7.4V.

    What version does the screen show at startup? We found a solution but your PowerBox needs to be updated in the factory. I think an update of the signal controller will solve this.

  • Thank you Richard for your quick response!

    I checked both of my brand new PB Royal SRS versions at screen startup and both are V04.2

    Yes, I am using dual duralites 7.4 5200 MAH and my servos are JR DS 8711. I tried with some futaba servos and same problem but with other servos I didn't notice the problem.

    Please give me instructions of the process how to send you both PB Royal SRS to your location. I can overnight them via Fedex. I bougth the units from Jack Price at Duralites.

    Gonzalo Martinez
    Northern California

  • Richard,

    I got the chance to perform some test on my second brand new PB Royal SRS and I am having the same issues.
    I bind it to my DX 18 as DSMX same issue. I bind it to my JR 12X as DSM2 and same issue. The movement in some cases at start will severly bind my linkages and and damage my moving surfaces on my jet.
    I am doing all these test on a bench and with several servos of different brands, specktrum, JR and Futabas

    What should I do next? please help!


  • Ich habe selbiges Problem bei meiner Royal SRS.
    Gibt es eine Lösung dafür?
    Ich verwende eine Jeti-DS16 im EX-Modus, Jeti RSat2 und JR-Servos Typ: DS8411, DS8911 und DS8915

    Gruss Beat