In the Haze

Certain servos connected to the R6014FS receiver move full one way and return to centre when system is switched on. Using TM-14 module in a 14mz.

This becomes a problem when full throw is not set up say on flaps etc and mechanically could damage the servo, retract valve or flying surface.

I have tried to re link to the TX but does not solve this potentially damaging occurance, as it occurs on every switch on.

Any suggestions?

Thanks.

Krysta

Hi In the Haze,

Can you tell us what servos you are using?


Sincerely,
Krysta
Product Development & Support Specialist
Futaba Service Center USA

In the Haze

Krysta,

Using JR DS9301 on ailerons (2) and flaps (2), 2 x JR DS8411''s on elevators, standard JR 361 on retract valve, JR 161 on rudder.

The channel selection is 1 elev, 2 elev2, 3 rudder, 4 ail1, 5 ail2, 6 throttle, 7 flap, 8 flap2, 9 Gear, 10 nose steering, 11 aux1 for turbine, 12 jetronics valve for brakes.

Flaps go down, both ailerons move down, retract servo full one way and then all return to centre when linked.

Edit: After reading the post I plugged in a futaba 9202 in the Aileron and Flap channels and it did the same thing. Also noted the elevator channels do not move because with the Skymaster hawk and digital servos, the elevators hang down anyway when it is powered off. On manually holding the elevators centred and powering up they do not move. In summary it is channels 4,5,7,8 and 9 that move although I cannot verify ch 6 (throttle) or 11 (Aux1) as they are plugged into the ecu.

rajul

My Feedback: (58)

My 14mz/TM14/R6014FS combo does the same thing with all Futaba servos. Any remedy to this?

Rudy F

Does it depend from the time between Tx-ON and RX-ON?

The 14mz-Tx needs more then 10sec for initializing!

Rudy

summerwind

i have this same issue with the servos going to full throw in one direction when switching the Rx on.................what worries me is that the servos are traveling past the EPA i have setup to keep them from going too far and into the binding zone..........this can't be good for them.
right now i'm using the 6EX 2.4 w/606Rx and 9001 and 9202's for my controla services on 2 planes and both do the same thing.

summerwind

Bill or Krysta,

i hate to bring this up to the top again, but is there any research on this problem in progress?

BalsaBob

My Feedback: (24)

From what I have learned on this issue ..... it has to do with whether or not the servo is analog or digital. The digital servos do not jump/move .... only the analog ones. What was explained to me is that: analog servos recieve voltage first ... and then a signal. Whereas, digital servos receive the voltage and signal at the same time. (this may be a simplified explanation ... but it seemed to make sense). I almost tore my retract valve apart (I was using an analog 3101). I replaced it with the digital version of it and the problem went away. Most of my planes use a mix of digital and analog servos .... only the analog ones jump at turn on. Bob

BaldEagel

Guys

I don't know if it applies to the Futaba, but with the Spektrum module in my Zap it was caused by not rebinding after setting controls ATV and fail safe, once I did a rebind the problem went away, hope this helps.

Mike

In the Haze

Yes been there on Spektrum, stripped 2 flap servos before we worked it out.[:@]

Re-linked the Futaba receiver but makes no difference. I have put in a powerbox digi switch to regulate the power to 5.5V as I am using a 6 volt pack and thought the fully charged pack providing at least 7 volts initially was the problem. No change.[&o]

Next is to pull out the turbine ECU and Aux plug from the receiver to see if that's the problem, can't see it but may as well try everything possible I suppose.

My other planes do not do this by the way, so that is why I am thinking it may have something to do with the turbine, but as I say I don't really think so.

Krysta

Hi summerwind,

I have been trying to recreate this here at my desk with no luck.

I of course do not have JR servos to try, but haven't had any problems so far with Futaba or Hitec servos.

I am not quite done trying out different combinations though. As I am trying to do this between regular work times, it may take me a little longer. Maybe til early next week.

Krysta

summerwind

hi Krysta,
i don't use JR sevos either.
my planes are all equipped with Futaba 9001's and 9202's. there is also another question (topic) related to this problem as is asked by others above right here,

http://www.rcuniverse.com/forum/m_7491461/tm.htm

although he calls it a glitch, it is something that is happening when turning on the Rx.

thx
mike

Ron S

My Feedback: (2)

I've just started using the 8 channel FASST receiver and model with a 8UA transmitter, and I get a deflection on all (3) of my control surfaces (they are also Futaba servos) when the receiver begins initialization.

It may not matter with this model, but I DO have another model where I have a couple servos that cannot move in a particular direction, otherwise a mechanical interference (and then, either high current drain or breakage) could be the outcome...

skorp_jon

It happend to me also with 14 channel 2.4 fasst.

When i turn on the receiver my servos go to one direction. In one or two seconds servos go back where they should be.

Krysta

Hi summerwind,

I am seeing a movement also, but only with a certain combination of servos.

We are forwarding this information on to Futaba Japan so that they can look into this for us.

I will let you know what I find out as soon as they inform me.


Thanks for the information, Krysta

Krysta

Hi summerwind,

I am seeing a movement also, but only with a certain combination of servos.

We are forwarding this information on to Futaba Japan so that they can look into this for us.

I will let you know what I find out as soon as they inform me.


Thanks for the information, Krysta

Krysta

Hi summerwind,

I am seeing a movement also, but only with a certain combination of servos.

We are forwarding this information on to Futaba Japan so that they can look into this for us.

I will let you know what I find out as soon as they inform me.


Thanks for the information, Krysta

summerwind

thx Krysta,

the other thing i have not tried yet is maybe to do the opposite of what we have always done here and turn on the Rx and then the Tx..................when i get homw today i'll give it a try.

mikw

quist

My Feedback: (198)

I had this happen on the bench ONCE. It was all 9156 futaba servos, I have never been able to recreate this.

summerwind

hi Krysta,
i won't get into the habit of bringing this up again and again, but has there been any answer to this issue?

thx
mike

Krysta

Hi Mike,

Sorry it took so long, this post got lost towards the bottom. But I did receive a reply on your questions about the servos moving on start up:


We have found some 2.4Ghz receivers may take longer to produce a drive signal to the servos when power is first applied. This is due to the high complexity of the receiver circuits and time needed to process information when power is first applied. Kind of like a PC which operates slowly at first when the system is booting and then runs at normal speed. You may see some horn rotation in non-digital servos until they receive the drive signal from the receiver. Normally digital servos do not produce this rotation due to the design of the servo amplifier.


I hope this helps, Krysta

summerwind

thx Kyrsta,

guess it's time to buy digitals from here on out.

thx
mike

underdw

My Feedback: (2)

How does this help? By letting us know that we need to buy digital servos if we want them to work flawlessly with Futaba's 2.4ghz stuff? Is there a workaround? Will there be a solution?
Oh, and we need to replace our Hitec digitals if we want them to work with the R6014.
Oh, the R6014 might not work anyway if you're flying on a hot day.

Ron S

My Feedback: (2)

I experienced this once again today (actually, every time I use this TM-8 with non-digital Futaba servos - it is very repeatable.)

Today, I decided to check to see if there is any load on the servo in the period after the servo deflects, until the receiver links up and commands the servos back to center. In this 1 to 2 second period, I can move the control surfaces. So for me, it appears there probably are no high drain concerns when it happens. Which means, I can live with the behavior. fyi...

summerwind

i ordered a few digitals, so i will report what happens when i get them.