JR G770 Gyro Setup Videos + some new 101's

[Finless]

Rudder end point adjustment is for PIRO rate ONLY.... It will not effect how far the servo moves the tail slider. If you get rudder end points low enough it will "look" like you are lowering servo travel and now it is working along with the stick better BUT you dont want to do this. Servo travel limits are set by the limit pot on the gyro ONLY.... Follow the instruction on your dual rate settings for piro rate (rudder end travel or dual rates that limit this travel).

Again, seriously forget what your seeing the stick do with the way the servo moves. Leave travel adjust at 150/150, set up dual rates to reduce that as I show in my vids, Set servo travel limits with the pot adjustment on the gyro, make sure everything is moving in the right direction, and Go fly...

Bob

[niconedz]

Originally Posted by Finless

Rudder end point adjustment is for PIRO rate ONLY.... It will not effect how far the servo moves the tail slider. If you get rudder end points low enough it will "look" like you are lowering servo travel and now it is working along with the stick better BUT you dont want to do this. Servo travel limits are set by the limit pot on the gyro ONLY.... Follow the instruction on your dual rate settings for piro rate (rudder end travel or dual rates that limit this travel).

Again, seriously forget what your seeing the stick do with the way the servo moves. Leave travel adjust at 150/150, set up dual rates to reduce that as I show in my vids, Set servo travel limits with the pot adjustment on the gyro, make sure everything is moving in the right direction, and Go fly...

Bob

Will do Bob.

You're a diamond... Thanks!

[apexc]

Originally Posted by Finless

NEW video posted! Understanding Gain 101!

Is this stuff working for you all?

Bob

all your videos rocks.... easy to understand.... straight forward .... simple words....

thank alot...

[apexc]

I have a question. Maybe it is a repeating question. Very sorry.

My setup on my HIROBO Sceadu...

770T + 8900 , DX7 with gyro menu and tail blades 92mm , HIROBO Freya Evo tail blades ( 90 size )

Question 1 :

I have read through this thread, on page 18 onwards... there is a member that has tail bounce back when releasing the stick after a piro. I did not see any feedback ( or I have miss out ) from the person who ask this question.

What I am having now is the same problem. Whatever gain value set in the Gyro menu in my DX7 .. it looks same to me... same problem... tail bounces when stick is back to center.

I have yet try out to relocate the ball link to be nearer. This bounce back will be worse when I do it during a static hover.... the bounces is really bad.

If the heli is slightly moving the bounce rate is not as bad during static hover.

What any posibble cause ? Area to tackle.

Question 2 :

I have try adjusting the limit on the gyro to get max travel of the slider. I noticed that when I reach a certain limit it is weird.

When I give max input to the tail... it moves to the max , then I center back the stick. During releasing the center stick , I did see that the tail blade will move back rather than staying at the max point. ( Bench testing ) .

In my common sense , during a hover , if I give a max input to the rudder to do a piro then I center back the stick to stop it , will the tail move back to counter back that will cause the tail bounce.

I have got a quite hot servo after about 3 minutes hover.


Any input is much appreciate.

Thank you.

[fast400]

so im running the 370/3500g combo, in normal flight mode this thing is beautiful.
BUT in idleup i CAN NOT stop a serious tail wag, i have been UP & DOWN the gain spectrum and it will NOT stop wagging.

i will try a second piece of gyro tape, but i dont have any vibration`s that are bad enough to send the gyro into a frenzy.

ive been down to 15% and up to 65% in the gain, i cant stop the wag.
in normal mode the heli/gyro is pefect, its the idleup that`s killing me. could there be to much slop in the plastic tail setup that could cause a tail wag in idleup?
or maybe the headspeed could be causeing this. im not sure the exact number, but im sure my headspeed is between 2700 and 3200 rpm`s. why do i think it`s this high? because im running the 35g on a 420motor with a 11t pinion.
ive had a few different gyro`s, and never had one act up in idleup if it wasnt acting out in normal flight mode.

[Yogi1]

Need to give a little more info.The % gain spread is quite large depending if your using gyro gain menu or just the gear channel.I'm running a 770/3500g combo on a 450sev2 using the gear channel for gain adjustment at only 13% and it holds tight no wag.Now i also run a 13 tooth pinnion which gives 3000 head speed you did not say what heli your flying but if its a trex 11tooth wont be near 3000. How long is your battery flight time.How far out is your control ball on the servo arm.More info for better answers.Yogi

[Canadian Man]

Just a note for everyone, I had a horrible wag on my raptor 50 that I could not get rid of. Read this post 3 times every page Finally took the gyro apart. The board in the gyro was loose. I put a bit of shoe goop along the edges of the board, let it sit over night, next day flew it and problem solved.

I hated this gyro untill I glued the board down. Now it's awesome!!!!!

Jonathan

[fast400]

Originally Posted by fast400

so im running the 370/3500g combo, in normal flight mode this thing is beautiful.
BUT in idleup i CAN NOT stop a serious tail wag, i have been UP & DOWN the gain spectrum and it will NOT stop wagging.

i will try a second piece of gyro tape, but i dont have any vibration`s that are bad enough to send the gyro into a frenzy.

ive been down to 15% and up to 65% in the gain, i cant stop the wag.
in normal mode the heli/gyro is pefect, its the idleup that`s killing me. could there be to much slop in the plastic tail setup that could cause a tail wag in idleup?
or maybe the headspeed could be causeing this. im not sure the exact number, but im sure my headspeed is between 2700 and 3200 rpm`s. why do i think it`s this high? because im running the 35g on a 420motor with a 11t pinion.
ive had a few different gyro`s, and never had one act up in idleup if it wasnt acting out in normal flight mode.

so i have replaced my two year old tail hub/grip`s and pitch slider.
i now can run in idleup with the gyro set in f.mode with the gain at 37%.
i have alittle tweaking to do on the push rod, but i can say i can run in idleup now.
i may still get the sonix`s cnc tail setup from www.cncheli.com and some radix tailblades, just to see if it has less slop than the stock plastic setup.
but im happy with this gyro now.

[luisg877]

Nice videos Finless, helped a lot, but i have still some problems.

i have a Thunder Tiger Mni Titan E325 SE, have this gyro + JR DS3500G servo, Spektrum DX7 TX + AR6100 RX. i wasn't the original owner. i won it on the "helis for kids" thread in the main forum.

motor is a Scorpion -6 with 11T, and the ESC is a Scorpion Commander 60A, that i think it delivers 6V.

the problem is that, when i punch the heli up, the tail gets a kick, it doesn't stay still as on your vid. and if i make the gain higer, i get the stepping piros.

i have a voltage stepdown for the servo, cause some have told me the servo only works with 4.8V, still, when i got it, it didn't have the step down, i added it later, should I take out the stepdown and test to se how it goes? also i have the ball on the inner hole, as on the outer whole had the limit pod at minimum and very small gain.

im using end point menu to set the gain, should i try with the gyro sense menu?

also, when it is in the ground, spooling up, it tends to wobble if the pitch slider is not that centered, making it turn left or right, like if it was with high gain, but when i get the slider at center, it doesn't do that, neither in the air.

can you help me please?

Thank you.

Luis

[Finless]

Luis, not sure I can help you other than some basic guidance. I never built a Mini Titan so I do not know the heli!

But one thing about small helis is you must have it dialed up for performance if you want the tail to hold like a rock! What I mean by that is the head speed must be up in the high range. If your head speed is low and you punch out for a HARD PITCH climb, 450 tails can only do so much! e.g. the gyro can move the tail slider all the way and it is STILL not enough to compensate for the torque! This is why you need a good head speed so you also get good tail speed and thus more power at the tail.

If you setup the gyro properly and it has the full control range (e.g. the slider can move max both directions) but the tail wont hold in climbs.... Then bottom line you are taking the tail control BEYOND what it is capable of in controlling against torque! It's not the gyro thats at fault... The tail cannot do what your asking it to do under the conditions your running the heli...... Again.... low head speed with lots of pitch is a COMMON mistake....

I have seen Sooooo many people come to me with "my tail doesn't hold" and they are running a linear throttle curve and really low head speed but they expect to NAIL the pitch (like >+12) and expect the tail to hold... NOT going to happen!

The JR770 is not a bad gyro.... Not the BEST in my opinion but OK... It will WAG in flight with too much gain but may not wag in a hover like other gyros... If you get wag in flight, your gain is too high!

So best I can tell you. I do not know the mini Titan and how the tail operates but hopefully you will figure it out........

Sorry I couldn't help more!

Bob

[Charlie Brown]

does the futaba s9256 work with the g770t

[Finless]

I hate to say this but did you watch my video explaining the functionality?

Please do.....

Bob

[luisg877]

Originally Posted by Finless

Luis, not sure I can help you other than some basic guidance. I never built a Mini Titan so I do not know the heli!

But one thing about small helis is you must have it dialed up for performance if you want the tail to hold like a rock! What I mean by that is the head speed must be up in the high range. If your head speed is low and you punch out for a HARD PITCH climb, 450 tails can only do so much! e.g. the gyro can move the tail slider all the way and it is STILL not enough to compensate for the torque! This is why you need a good head speed so you also get good tail speed and thus more power at the tail.

If you setup the gyro properly and it has the full control range (e.g. the slider can move max both directions) but the tail wont hold in climbs.... Then bottom line you are taking the tail control BEYOND what it is capable of in controlling against torque! It's not the gyro thats at fault... The tail cannot do what your asking it to do under the conditions your running the heli...... Again.... low head speed with lots of pitch is a COMMON mistake....

I have seen Sooooo many people come to me with "my tail doesn't hold" and they are running a linear throttle curve and really low head speed but they expect to NAIL the pitch (like >+12) and expect the tail to hold... NOT going to happen!

The JR770 is not a bad gyro.... Not the BEST in my opinion but OK... It will WAG in flight with too much gain but may not wag in a hover like other gyros... If you get wag in flight, your gain is too high!

So best I can tell you. I do not know the mini Titan and how the tail operates but hopefully you will figure it out........

Sorry I couldn't help more!

Bob

thanks for the reply, let's see, im running the throttle curves like this:

normal: 0% - 100% linear
idle up 1: 100% 75% 100% no expo
idle up 2: 100% 85% 100% no expo

and the pitch is:

normal: -2, 0, +12
idle up 1 and 2: -12, 0, +12

is that ok?

and is the voltage stepdown neccesary for the tail servo?

thanks.

Luis

[luisg877]

update:

changed the middle stick value on the throttle curve on all modes.

Normal: 60% middle stick

idle up 1: 80% middle stick

idle up two: 90% middle stick.

haven't flown it yet.

[j bomb]

Originally Posted by Charlie Brown

does the futaba s9256 work with the g770t

The short answer is no, it will not. The G770 only operates at the standard center pulse, it isn't selectable like some other gyros. The S9256 is a "narrow pulse" servo. If you want to use a Futaba servo w/ this gyro, go with an S9254 or BLS 254 instead.

[seanh]

got a 7703d...anyone know if it will work with the 8700G?

if it makes a difference, it's going on a Rex 600E

[pmadera]

bob, in these videos you refer to the dx7 can i use the same concept for dx6i, i cant seem to get my tail to stop twitching using the jr770 on my trex 500 with the ds520 tail servo and dx6i.

[n8rloves2fly]

Looking to try the 770 what is the servo? Knight 3d

[fast400]

ds3500g or the ds8900g, im not sure what size your heli is classified. from a 500 class down i would say the ds3500g, 600 and up i would say the ds8900g.

[fast400]

Originally Posted by fast400

so i have replaced my two year old tail hub/grip`s and pitch slider.
i now can run in idleup with the gyro set in f.mode with the gain at 37%.
i have alittle tweaking to do on the push rod, but i can say i can run in idleup now.
i may still get the sonix`s cnc tail setup from www.cncheli.com and some radix tailblades, just to see if it has less slop than the stock plastic setup.
but im happy with this gyro now.

well,
i have the 770/ds3500g combo now as well on another 450 heli.
i did a rate mode set-up on the g370 & the g770 and it works very well, but am now thinking of try the center slider set-up to see for myself the difference in these gyros performance.