RC Model Reviews

Re: Review: Turnigy 9X version 2 (FHSS).

New postby francoishaha » Tue Oct 18, 2011 2:03 am
ok, i just receive my turnigy 9x, i read about the failsafe. I just want to be shure about what i read cause im not excellent in english.

Im running electric plane, if i lost signal the motor turn off right?

Hi Francois,
The flysky module and receiver supplied with the 9x do not have a failsafe as such the servo output pulses just cease.
However luckily for you most escs cut off when there is no input pulse so that effectively you will have a throttle cut failsafe.
Glow and petrol engines would continue to run at the throttle setting they were at when the signal was lost.
Regards,
Bill

i havent actually checked with the flysky receivers but the vast majority of receivers without failsafe will centre all channels with no signal
so while they dont go into a failsafe setting both an esc and a throttle servo should go to idle

also a nitro engine should always be equiped with a mechanical failsafe such as a spring that pulls the carb shut in case the receiver battery runs low

i havent actually checked with the flysky receivers but the vast majority of receivers without failsafe will centre all channels with no signal

Let me reiterate the flysky receivers simply cease to give an output pulse I have actually checked on a scope.
Servos go floppy undriven and do not hold position.
Flysky/Turnigy RX gives No Output Pulse it does not give a 1.5 ms pulse to "centre" the servos (this would be of no use on the throttle would it).
The Frsky receivers (information based on the DR8 V2) have a settable fail safe, but if you don't set it the output freezes on the last good input signal. Servos are held in position by a repeating pulse train.
Early type pcm systems would also freeze on the last good signal.
"Receivers without fail safe "arbitrarily" moving to a "centre" would serve no useful purpose and the circuitry / programming involved could have been used to implement an actual fail-safe!!!
Detection of no signal and centering the servos would be implementation of a fail safe of sorts, perhaps you are confusing this with the freezing behaviour of early pcm.
How would a spring on the throttle help?.. the servo would have to fight against it all the time and cause a constant high current drain.
I look forward to seeing your actual working design for such a spring fail safe, surprise me....!

well thanks for all the rage

anyway it usual helps your forum experience if youre able to read
the spring is for pulling the throttle shut when the rx battery runs low and both the rx and the servos are unpowered
which is particularly good fun if it happens in an 100+ kmh rc car or eg a pylon racer at full throttle

Shotglass wrote:well thanks for all the rage

anyway it usual helps your forum experience if youre able to read
the spring is for pulling the throttle shut when the rx battery runs low and both the rx and the servos are unpowered
which is particularly good fun if it happens in an 100+ kmh rc car or eg a pylon racer at full throttle

Hi,
Where I fly my club strongly recommend charging battery packs before every flying day so there is no excuse for crashing because of a flat battery.
A binding servo will quickly drain power and having a spring strong enuf to turn a servo arm when Rx stops will allso excessively drain your battery.
Best option is a in line Fail-Safe device inbetween the Rx and the servo, problem solved. Thay are dirt cheep from Hobbyking.

Aussie Joe wrote:Where I fly my club strongly recommend charging battery packs before every flying day so there is no excuse for crashing because of a flat battery.

mistakes happen its a fact of life and the point of a failsafe is to at least limit the amount of danger a runaway plane poses

A binding servo will quickly drain power and having a spring strong enuf to turn a servo arm when Rx stops will allso excessively drain your battery.

first of all most modern digital servos can be moved with nary a nudge when they are unpowererd
and for that reason all you need is a rather soft spring that wont have any appreciable impact on rx battery useage

Best option is a in line Fail-Safe device inbetween the Rx and the servo, problem solved. Thay are dirt cheep from Hobbyking.

no because it isnt a catch all
couple of years ago a friend of mine crashed his serpent vector when the throttle servo cable rattled itself loose dragged along the road and disabled the servo at full throttle

these things happen from time to time and when you fly or drive something with enough power to injure someone its important to make sure you cover all possible mistakes and mishaps that can and do happen

well thanks for all the rage

anyway it usual helps your forum experience if youre able to read
the spring is for pulling the throttle shut when the rx battery runs low and both the rx and the servos are unpowered
which is particularly good fun if it happens in an 100+ kmh rc car or eg a pylon racer at full throttle

Well thanks for reading what I wrote in the first place (not). "it usual helps your forum experience if you're able to read"
You completely ignored the facts I stated about the Flysky RX, then gave uninformed views on the functioning of radio equipment in general, my question to you is why? If you don't know something why venture an uninformed opinion?
I was trying to advise someone who wanted the information, why confuse them?
I can read and spell and punctuate something your posts show a lamentable lack of.
I offered you a chance to redeem yourself with your spring idea...... the scenario of a completely flat battery and the qualification of a digital servo might I suppose be credible.
But maybe I'm being a bit hard on you let's stop this now If you get my point I get yours.

Shotglass wrote:mistakes happen its a fact of life and the point of a failsafe is to at least limit the amount of danger a runaway plane poses

"mistakes happen" yes, "failsafe is to at least limit the amount of danger a runaway plane" yes we all agree with that, BUT you still have a duty of care to club members and the general public to have your model as safe as you can. Being in a large club over many years I get to see a lot of scary and dangerous stuff.

first of all most modern digital servos can be moved with nary a nudge when they are unpowererd
and for that reason all you need is a rather soft spring that wont have any appreciable impact on rx battery useage

I use a lot of servos and seen a lot, but none that can turn with a soft spring.

no because it isnt a catch all
couple of years ago a friend of mine crashed his serpent vector when the throttle servo cable rattled itself loose dragged along the road and disabled the servo at full throttle
these things happen from time to time and when you fly or drive something with enough power to injure someone its important to make sure you cover all possible mistakes and mishaps that can and do happen

"Dragging a servo cable along the road to disabled the servo at full throttle" that was very lucky, but to recreate that with a spring on the servo or throttle arm may seem ok except for the power drain. Ok maybe a very very very lite spring on the throttle arm, but for me all my models big and small are over engineered and get checked to a MAAA fixed wing standed for everybodys safety and the clubs future.

"Re: Review: Turnigy 9X version 2 (FHSS).
by RCModelReviews » Wed Sep 28, 2011 7:12 am

Although I haven't tested it, a JR-type Spektrum DSM2 module may work -- if you can find one.

The problem is that the antenna on the 9X is hardwired in so you can't easily put the Spektrum module in the back.

Better to buy the PNP version of a model (if they make one) and just throw an $8 HK 6-channel receiver in it instead.

Of course that's not practical for some of the really small BNF (like the Beast or the Vapor) I guess."
_____________________________________________________________________________________________________
Have my turnigy 9x converted to accept JR and frsky modules. really want to use the dsm2 or dsmx system to operate
spectrum receivers. Does the JR dsm2 or dsmx module work with the turnigy 9x?

Hello, could someone tell me how many models the Turnigy9X will keep in memory? My DX6i remembers the settings for 10 of my models. If the T9X only stores one model, then I'll stick with spektrum.

Thanks a ton!

Beast