Heli Jive: is calibration needed?

[abanihani]

As the title said, do we need to calibrate heli jive like the other jives to get rid of the dead band using the internal governor option?

[MrMel]

You have same deadband as other jives on the Helijive, but you cannot calibrate it if you use Autorotation bailout, since it using that deadband as part of the AR bailout.

Covering it in here;
[ame]http://www.youtube.com/watch?v=c_Wz4KUzjXA[/ame]

[abanihani]

Thank you, makes sense.

[jointer]

Mr. Mel, do you have a JLog device?
I found out the throttle percentage reported by JLog matches exactly the value from my radio, so there is not any reason why to do that "calibration".
I see no reason why to remove the "deadbands".

[MrMel]

Its rather for those that do not have a jlog, as you have jlog its a different story as you have lots more info.

Does your jlog throttle % match that you have in the radio throttle curve?
The reason for calibration in first place was to normalize between different radios as it differed 10% between futaba and spektrum, which raised questions as many do not use tachs

[jointer]

I do not want to offend you, but by my opinion, the calibration is completly useless.
The Jive is calibrating the endpoints during programming, so no matter what brand is the radio, internally the Jive learns where 0% and 100% is, every time.
If you mean different servo impulse between brands, then this is eliminated by the Jive.
Removing the deadbands is good only for better throttle channel resolution, but i doubt this have any effect in real life.

What is it good for? You can compare the % without this "calibration", because the throttle the Jive "see" is already the same.
It can make things tiny bit worse actually, because someone might remove 18% of the deadband and someone 22%...
And if i want to reprogram the ESC, i must reset the ATVs back to original, else i am in endless loop, because Jive probably learns the adjusted travels as new max and min value.

I verified the throttle % in JLog is the same like the value comming from radio, Jive 80, 120 and two radios.
The error was zero or maximum 0.5% (maybe resolution issue).

[MrMel]

The reason is simple, no it does not add same headroom for all radios, it adds different deadband depending on brand, thats why we all started with this back then.

Why? Simple, headspeed calc like mine on hits 10% wrong and same goes for anyone comparing throttle curves which happened a lot on the forum if you search back.

Performance wise or if you have a tach, yep its useless.

For the guy that do only use the headspeed calc, i beg the differ.

Today its not as much of an issue since radios is coming together in this aspect.
(you still see part of it in the different tx trim you have to do in the vbar)

[jointer]

Originally Posted by MrMel

The reason is simple, no it does not add same headroom for all radios, it adds different deadband depending on brand, thats why we all started with this back then.

Okay, i did not know that.
I do not have different radios to discover that, you probably do.
But you never get the same results on different setups, there is always a difference with the motors, batteries, i also noticed mode 4 and 11 spins different RPM on the same throttle value.
JLog allowed me to see that the Jive sets the endpoints correctly.
There is a deadband, but i do not know why i should mess with them, just to have the throttle matching with some calculator on the web.
Sorry, i believe they are there for a reason.
No offence: good try, but you did not convinced me that i should do that, no advantage for me.

[MrMel]

Like I said, you have a JLog, no need for you at all.

I have made the worst (for the wallet) possible choice when swapping radios, I actually swapped brand each time, Ping-pong between Futaba, Spektrum, JR, so yep, tested lots of them.

[dl7uae]

JLog allowed me to see that the Jive sets the endpoints correctly.

Yes, of course.

Well, everybody knows that I cannot be called a fan of this "tweaking throttle"...

But: If Fredrik speaks about "throttle calibration" he means to remove the offset throttle./.PWM, stretching throttle travel to match PWM travel. And PWM is RPM, THROTTLE is only the mediator.
The reason is clear and already explained by him: Everybody who tweaks his throttle travel that way can expect more accurate results from the HS calculator.

If you tweak the throttle travel after teach-in of the JIVE, please note the following:

- The uplift throttle/PWM is not constant over the throttle travel.
- It is also kinda security feature. The throttle pulse length may drift a bit and may have a TC (in the transmitter and the receiver). Let some "air" around the bottom.
- The uplift in the H/JIVE differs a bit from that in a "normal" JIVE.
- And: As said by Fredrik: Don't do it if you have a programmed bailout value. You would tweak it away.

Tom

[helicraze]

I never calibrate my jive. But swapping out all my jive 120hv for helijive i find instead of around 67%thr i am down to 60-64%.

[chopstick]

I must have mssed something. Why are mr Mel's vid' s private?

[desertstalker]

Originally Posted by chopstick

I must have mssed something. Why are mr Mel's vid' s private?

Kontronik told him to take them down...