RX2703H-D Receiver and gyro gain

I have the Walkera 450D03 with the RX2703H-D receiver ( I also have the same receiver in an HK 500), Devo 8 radio and deviation firmware, I've never owned head holding gyros before so I really don't know if this is a common thing or even a problem, on both helicopters I can fly them sideways as fast as they will go and the tail will hold, but from a hover if I crank the throttle real fast the helicopter will rotate, it also does the same thing in a fast decent from a hover in the opposite direction of course and only about half as severe, I didn't really think this as very odd I just thought I will increase the gain until the tale starts hunting and then back it off a little, and this is the part I find odd I've gone from the 70% gain where I started up to 100% gain, the rotation is still there on fast acceleration from a hover and I never did hit the point where the tail was over sensitive and hunting, on the older gyros I have I would just put in up mix and down mix to correct this but my understanding was that head holding gyros are supposed to eliminate this issue, I'm wondering if anyone else with this receiver has been able to increase the gain to the point where the tail is over sensitive and hunting, I'm just using the standard GUI I have downloaded and tried a file with the advanced settings with the exact same results.

Hi,

12 lines, one sentence, just commas and one point at the end. This is really VERY HARD to read and understand for me and probably others. Maybe it's just me being a non native English speaker...

Please can you rephrase, add some blocks and multiple newlines? Thanks.


What does "crank the throttle real fast the helicopter will rotate" mean?
The throttle output is the same speed always?
What is the throttle value in Idle-Up / ST1 / FM1?

Do you mean you try pitching?

When you do pitching, do you have a V throttle curve? There are some ESCs which do not work well with one flat throttle value.

When you do pitching do you mean that your tail drifts 45-90 degree sideways in both directions?
The the tail hold in steady hover without drifting 45-90++ degree sideways?
With a weak tail hold the tail usually drifts to the right.
There may be a wrong mechnical tail setup (over pre-comp) if it drifts to the left.

For some HH gyros you just choose the middle of the pitch slider and let the gyro work in the HH and it should hold the tail well.
For my Blade 450 with G210 MEMS gyro I choose to mechanically set the tail in rate / normal mode and then switch over to HH.


Some helis cause bad vibrations which will get your FBL or tail gyro crazy.
The same is for belt driven helis. They need to have the right strengths. Not too tight.
Too tight and it will cause vibrations = gyro goes crazy = drifts (I had even seen 180 tail drifts!)


If you you can not see any difference for raising or reducing the tail gyro HH gain for your tail (starting hunting, holding, tail drifts sideways WITHOUT pitching) something is really bad.


I do not know the Walkera FBL / RX2703H-D receiver, but you should be able to reduce the tail gyro gain also.
Then it will start to drift at some point at constant hover.
Same for pitching when it does not hold anymore.

You are correct with go up until shake and then reduce 1-2% concept.


The advanced GUI has -100 to 0 for normal / rate and 0 to +100 for HH.
I am not sure about the standard mixer GUI right now if those -100 - 0 - +100 gyro gain values apply too.

Personally I fly my Blade 450 3D (no FBL) with 52-56% tail gyro gain in HH mode.


You might also want to check if you and do mechanical adjustments to the tail so it holds well even in rate / normal mode.
For that you would have to switch the gyro.
I am not sure about the RX2703H-D if setting the tail gyro gain <0 works or if that will disable the FBL completely (just like with the Walkera FBL on the V120D02s).

I hope you find some more threads about 450D03 and RX2703H-D and tail / gyro optimizations.
You can also try HeliFreak and RCGroups.


I just can think that you crashed your heli a time ago and you did not replace all bad parts which now causes bad vibrations and your FBL/gyro going mad.

Be careful: This may also mean that your cyclic gains (FBL) is not working right!!

Greetings

Thomas

Thomas thank you for the reply, sorry about having it all in one sentence.

I guess I had over complicated the question, I was only trying to describe what led me to playing around with the gain.

What I meant by cranking the throttle was going for collective.

I do know I have a good clean setup with no vibrations, I've been bashing RC helis into the ground for a little over 30 years though I have no experience with head holding gyros and little experience with electric helicopters.

I have approximately 40 flights on the helicopter, approximately 20 on the original software that came with the radio and 20 with the deviation firmware upgrade, no crashes no hard landings.

As I said I probably overcomplicated the question, the only question I really was looking to have answers is has anyone ( running the original software or the deviation firmware upgrade with either the simple GUI or advanced GUI) and that is running this receiver been able to increase the gain to the point that the tail is twitching or hunting, the reason I'm asking is that there seems to be absolutely no difference between 70% gain and a 100% gain.

At the moment this is somewhat of a moot point because the receiver has seemingly packed it in, all the receiver does now is flash 8 times rapidly pause and just repeat that sequence continuously and will not bind to the transmitter.

What is the difference you can see between 14%, 52, 56 and >60-70% gyro gain (all HH >0)?

There IS a difference for sure on my G210 MEMs tail gyro (not speaking about 70-100%).
For some issues with my belt I had not seeing much gyro gain difference first too.

You are right - it might be a RX2703H-D receiver issue. I can't tell, sorry.

There may be even differences on hover vs speed curves.
Suddenly my tail was hunting / shaking in the curve when actively flying but not in stable hover.
This was with a new (different) motor.

Pardon for asking but are you sure you have selected the right gyro channel and assigned the right switches in DeviationTX?
You could check your channel monitor.

There are so many good FBL systems with HH gyros around, that you may want to test something different?!?
See the other heli / fbl threads and suggestions about BeastX Plus/Pro with "Spektrum SRXL" (AR9020) or Spirit System FBL, V-Stabi, etc. (even working over PPM digital connection).


Are you sure that the RX2703H-D is any good FBL which lets you properly tune the settings?
Are there any threads about it on HeliFreak/RcGroups?

If it does not work as you expect / want to tune it in - I would probably not waste my time with it personally