This is wat I used GA250 to test the servo.
U will notice the different in the performance for servo.
Either U got bad results or improve, although it is still not a good HH gyro.
I had better results with GA250 with different servo, although it is still having some bad firmware performance issues.
With a good gyro it is difficult to differentiate the performance of servo.
Because good gyro(Spartan) is so good that always having good performance with cheap servo.

I have never seen a good 3D video of the assan ga250, and I will never expect it. Someone said they had Oliw's firmware and they got good results with the assan gyro, I told them show me some long tailslides with it, and that was over a month now and still no video. Dude I've heard it all with that gyro. sorry to say but that assan ga250 is a POC. I wouldn't test any servos on that gyro. If you know what I mean. If you really want to test out tail servos, try it with a spartan quark then judge how those servos really perform.

I've heard this servo is a true performer.
http://www.hobbyking.com/hobbyking/s...06sec_21g.html



but please test it with a quark and not on an assan gyro

I yet to try that similar servo on HB790, I got a relabel KDS.
I'll had it on GA250 as well....can't say it is good or not, u know I always have better with Innolab.
But this servo does transfer the heat so well that the boom can get warm up easily.

Did more testing with Hitec5084 servo, reduce frequency rate to 250hz & 5V BEC initially was 333hz with 6V BEC setting.
Normal flying was ok just little warm up for 5084 servo.
Once idle up more aggressive flying etc, heat still accumulate for the servo.
Although it is not burning heat like before, temperature is too high to operate in this condition.
The servo motor sure to fail at this high temperature working rate.
The life span for the servo would be very much shorter than normal.

I'm done with Hitec servo, HB790 is not suitable for HItec.
Will order Inolab servo for more testing with HB790.

Originally Posted by Tovin

Did more testing with Hitec5084 servo, reduce frequency rate to 250hz & 5V BEC initially was 333hz with 6V BEC setting.
Normal flying was ok just little warm up for 5084 servo.
Once idle up more aggressive flying etc, heat still accumulate for the servo.
Although it is not burning heat like before, temperature is too high to operate in this condition.
The servo motor sure to fail at this high temperature working rate.
The life span for the servo would be very much shorter than normal.

I'm done with Hitec servo, HB790 is not suitable for HItec.
Will order Inolab servo for more testing with HB790.

kool let us know Tovin which servos are compatible with this gyro! good job. thank you

Now waiting for Inolab HGD261 & Power HD3688 servo.
Most probably had to wait for a week, while still waiting for Goteck to arrive.
Seems take quite a while for my previous orders to arrive.
Will take a break, & resume my physical exercise training which I had stop since a year ago.
Age had catching up, need to reshape my physical body.

Today finally received all 5pcs of HB790, took a while for the shipping.
Tested on two 250 clone, one with Walkera Devo8 & Hitc Aurora9.
It reveal the flaws found on HB790.
Also reveal the HXT900 servo issues with Walkera receiver.

The HXT servo having strange sudden oscillate partically only at Aileron signal channel.
This sudden peak oscillation caused cyclic throw and my 250 clone just flip to the right & down to the ground during high head speed idle up throttle.
I had this issues since install the HXT servo in the begining with Walkera Devo8 receiver setup. And later try add in external 5V3A Hobby wing BEC still having the same problem.
Install HXT servo with Hitec receiver setup with cheap ESC(without external BEC), no servo oscillation issues found.



For the HB790, it reveal the flaws found on rate mode at low gain issues with Walkera setup.
At rate mode if gain below below 28 the tail will ocillate & wagging like a dog, above 30 would be normal .
This is really strange, I don't encounter a gyro will cause tail oscillation at low gain rate mode. And it really oscillate very very badly eventually it will lost control. I nearly lost control during test fly trying low gain at rate mode.
All other previous gyro(cheap or bad gyro) either the tail will stay or rotate at one direction for low gain rate mode.
The gain had to set much lower in HH mode, compare to 450 size.
If too high gain 68 & above the tail will not hold during fast piro stop, it will wag badly near crash suituation during hard piro stop.
The HH gain will be fine around 60~65.
This is same gain with Hitec Aurora9 transitter.

As for the tail servo, Inolab servo is working fine without heat problem with 333hz setting.
So far HB790 will hold 250 size if setup corretly on the gain isues.
However internaly I found it may be still suffer with the hardware(cheap china made chips?) issues used in it.
Anyone tried open HB790 servo?

Summaries for HB790 performance.
It is still not the same performance compare to Spartan.
It performs so well on 450 size as good as Spartan.
Down to 250 size, U'll need to lower gain(10% lower than 450 size) further to eliminate the wag issues during fast piro stop.
And of course it is much better than GA250, although holding is not as crisp as 450 size it is still holding good if gain setup correctly for 250 size.

what was your gain on the 250 and the 450?

Originally Posted by pitchp

what was your gain on the 250 and the 450?

For the same transmitter(Hitec) & receiver setup.
Gain for 450 ~76, 250 ~ 63/66 range.
Both tail servos are set at 1520us 333hz.
Eventually I will need to lower the frequency to 250hz on the 450 for Hitec 5084 servo due to high temperature issues. But gain still remain the same.
I will replacing the Hitec servo soon, when Inolab servo arrive.
It is by far best tail servo I had used comparing to Align DS520 & DS420.
The Hitec5084 is also a good one but it just too hot to be use with HB790.

all the best with the inolab, hopefully that will stay kool for you. let us know how you go.

Now the 250 is so much better now with HB790, after trying so many gyro.
It never been holding the tail before with hard piro stop.
No drifting, no wagging, good stopping.
It is so difficult to get a good gyro for 250, so much different and less tolerance to setup 250.
And flying is also more difficult comparing to 450.

I will get more 250 clone now as HB790 is up to the task.
It is so cheap for 250 parts & kits.
More easy to fly in small park or area.

I just got burn out servo for KDS N300 similar servo as KST DS115/TGY-S306 install on 250.
It was holding well until it was dead during test flight when I was trying rate mode at low gain which the tail wags very badly.
I found most of servo are working very hard with HB790 gyro, the tail servo heat up easily especially during idle up high throttle output.
I found 3pcs of Henge servo MD922 from the old box & decided to replace the dead servo.
It is working fine with the same settings but @ 250hz frequency.
Can't feel the heat up temperature due to the thick plastic casing on MD922 servo.
Not sure if it will last longer than expected.

Also did try out the Goteck D9257 servo on 450 for replacing the Hitec5084 servo.
The frequency is set @ 250hz, but I don't think the servo can hold the stress at 333hz higher frequency.
Need to slightly lower the gain to reduce the slight bounce on hard piro stop.
It is holding well, but not as good as 5084(better torque & resolution) servo.
The Goteck D9257 working temperature just slightly lower than 5084.
Not sure if it will last longer, I will just leave it on for further testing.