nonstoprc

My Feedback: (90)

Yesterday at the field, immediately I confirmed the “on air” status on the radio (12Z, with the receiver R617FS on already), I found that the servos acted strangely. For example, the left aileron servo pushed hard for a full deflection of the aileron. So did the rudder servo. It lasted about one or two seconds and then the servos returned to normal center/neutral positions. The radio has full control over the receiver and servos after the “incident”. I did not fly for safety concern.


Since then, I was not able to reproduce the problem.


The receiver battery is fully charged and has a voltage of 7.9v (regulated to 6v). The battery on the radio is at 60% full.



Welcome any comments/suggestions to help explain it.

grotto2

My Feedback: (2)

What do you mean by confirming "on air" status? Are you turning the receiver on before the transmitter?

You should always turn the transmitter on first and off last.

BTW, have you set your failsafe?

nonstoprc

My Feedback: (90)

12z does not send signals over the air unless confirmed to do so by pushing a button.

yes I could power on the receiver after the radio. But I do sometime reverse the sequence.

Fallsafe is set and should not be a factor because the radio is just sending the signals over. There is no fail event.

Jeff Worsham

My Feedback: (28)

Following as Grotto says- Tx on first and off last, I've never seen funky servo movements with my 12z. Always "On Air" and transmitting before turning on the receiver.

apereira

On Futaba , if the Tx is not turned on first, the fail safe might not work correctly, as every time you change something on it, it gets programed on the Rx at start up.

rcpattern

My Feedback: (45)

With the 617 and using 7 channel FASST, only the throttle is supported in failsafe, so it would not be a failsafe issue.

Arch

apereira

correct Arch,

I didn't think it was necessary to explain, but especially with throttle my point was the huge importance of turning the Tx on first always as this can affect the failsafe operation later, tha's all.


regards

Alejandro P.

nonstoprc

My Feedback: (90)

Thanks for all the inputs.

Just to clarify on failsafe. The incident happened with the attempt to fly the 4th flight on that day. there is no change of any failsafe settings prior to the flight.

Now on the importance of turning on TX first. Does it mean that TX could send "bad" signal during initial transmission? If so, this could explain it. But since it happened only once with the 12Z and hardly reproducible, there must be some real issue (such as intermittent connection) with the radio?

JRgraham

My Feedback: (1)

When Rx is on and no Tx signal found, the Rx will be searching for a signal. When nothing is found, the Rx can/will send transmission to servo's, servo's will desperately try to find their centering signal.. and can sometimes simply go full travel to one end point because there is no signal yet to tell them where to center..
The Rx has to have a Tx signal on prior to its power up. And also needs to be powered off prior to the Tx, or it will again search for signal and servo's will be 'lost' and may again power themselves to an endpoint trying to find a center signal..
Im no electrical engineer, but thats about the laimens way of putting it.
Tx on, then Rx... Rx off, then Tx and thos problems are gone.

Now on the 12z that has the transmission or 'on air' confirmation on power up, you need to also wait and confirm the 'on air' status completely prior to powering up the Rx too.

nonstoprc

My Feedback: (90)

Thanks for the theory. It may well be that the receiver was acting like that. One exception is that the behavior could only be observed once in multiple tests following the incident.