DX7 and gyro sens.....a design flaw perhaps?

[flingwing403]

ok this is what i just found out with this dx7 in regards to gyro sens.

first in the set up i have aux2 inh and gear as gyro.

now before i go further i am familiar with how it works and the proper settings for standard vs hh mode, anything below 50% is standar and anything above is HH. this would also imply that moving the switch from pos 0 to pos 1 would change said gyro from stanad mode to HH mode

in the gyro sens screen it gives you 2 choices, the first is using the rudder d/r switch which i refuse to do since i have and use this as my throttle hold for safety and crashes.

the other option "auto" uses the gear switch...or aux 2 if thats how you ran it.

problem is in this mode the gear swich is now useless and moving from pos 0 to pos 1 does nothing, the blinking light on the set up screen does not change from 0 to 1 based on the gear switch??

next to it is the f.mode options for norm/flight1/hold..these can be given a value of either 0 or 1....

so this means if you had norm at 0 and flight1 at 1 you would go from standad mode in norm to HH mode in flight1?

i know i can just put all values to 1 or raise the 0 value to my desired gain setting..BUT again..isnt the idea of having a switch to be able to "SWITCH" from one to the other??

lets say i'm hovering in HH mode and wanted to do something in standard i cant just flip a switch to do so....yes i know if i use the rudder switch i could but again its not an option as i preffer throttle hold.

so with this set up i need to land, scroll to my gyro sens in the set up screen, lower the value below 50% to get a standard mode then fly again, land when i'm done and switch it back..

am I missing something, or maybe its ment to be this way and my newb'ness just hasnt figured that out yet?

do all your dx7's run the same way?

[capebob]

The best way to set up the DX7 IMHO is to disable the gyro sense page and control your gyro with the gear switch. Then you're able to use throttle hold and idle up without changing your gyro mode and be able to control your gyro with the gear switch. This is a limitation of a 7 channel radio with a limited amount of switches.
Bob

[flingwing403]

thanks bob, i take it that in this version you would use the gear channel end point settings to determine your amount of gain??

is this how you use it as well? trial and error again i take it to find the proper gain

[capebob]

That's how it's done. For a glow powered heli or a large (50) electric and a 401 gyro, start with +- 80. For your T-Rex with about +-65. There are a lot of variables that will change the highest amount of gyro gain you will be able to use. Among those are the smoothness of your machine and the speed of your tail rotor servo.

Bob

[Jermo]

the other option "auto" uses the gear switch...or aux 2 if thats how you ran it.
Not exactly. Auto just uses the assigned switch to control the gain settings. There's no need to go out of Heading hold but if you did want you you'd likely be using a flight mode to do it. That's exactly how the DX7 Gyro sense menu is set up.

I don't know of anyone who flies the T-Rex with a 401 in Rate mode. The Gyro must be initialzed in HH mode before use.

I just set both 0: and 1: to 72 and fly. If I power up my heli and move it to the flight line I wag the tail quickly 3 times and it resets. This assumes I correctly initialzed the Gyro in HH mode at the start.
Jermo

[DavidH]

If I power up my heli and move it to the flight line I wag the tail quickly 3 times and it resets

Resets what? What does wagging the tail of the heli do?

David

[Jermo]

Same thing as cycling the gyro between HH mode and Rate 3 times quickly ;)
Jermo

[DavidH]

Wagging the tail of the heli does the same as flipping the switch 3 times to set the neutral the same between AVCS and Normal mode?

That is a new one on me. Don't see how wagging the tail of the heli does that.

David

[capebob]

David,
Rapidly moving the tail rotor stick with a 401 gyro at least 3 times resets the 401s neutral. The tail doesn't actually have to wag. :)

Bob

[DavidH]

Bob,
Yes I know flicking the rudder stick will center the servo.
But that is not the same as flipping the switch 3 times back and forth between AVCS and Normal ( rate) mode.

I was just trying to figure out how wagging the tail of the heli had anything to do with something on the transmitter.

David

[Finless]

Yep David... moving the stick back and forth fast 3 times will recenter the gyro... Try it :)

Bob

[flyinfool]

Yes I know flicking the rudder stick will center the servo.
But that is not the same as flipping the switch 3 times back and forth between AVCS and Normal ( rate) mode.

I agree with David and the manual.
It is a terminology thing here.
Resetting vs recentering.

Flipping in and out of HH 3 times in less than 1 second resets the gyro and causes the gyro to "learn" the current rudder stick position as center. This is a reset.

Moving the rudder stick back and forth 3 times in less than 1 second and immediately centering the stick will return the servo to the previously learned center position. This is recentering and the servo center is gone again as soon as the heli or stick is moved.
This function is only used needed for bench testing and is the same as switching to normal mode.

This is clearly explained in the first 2 bullet points on the first page of the instruction sheet.
http://manuals.hobbico.com/fut/futm0807-manual.pdf

[PsychoPilot145]

now before i go further i am familiar with how it works and the proper settings for standard vs hh mode, anything below 50% is standar and anything above is HH. this would also imply that moving the switch from pos 0 to pos 1 would change said gyro from stanad mode to HH mode

in the gyro sens screen it gives you 2 choices, the first is using the rudder d/r switch which i refuse to do since i have and use this as my throttle hold for safety and crashes.

Darn... I am sorry I did not see this thread when you posted on mine last night. OK, if you have not figured it out yet, you are having EXACTLY the same issue that I did. I could not manually with a flick of a switch go from normal rate, to HH. This is a requirement to enter the quick setup mode on my csm gyro. http://www.helifreak.com/viewtopic.php?t=34149

If like me and you want to be able to manually go from normal to HH with a switch, Jermo's video is not the way to do this. If you want to use the gear switch, you have to set the gear, to gear. With the gear switch set to gyro, the switch is inhibited, enabling the auto function for the gyro. Personally, I have the HH switch set to my AUX2, so it is right next to my throttle hold switch.

Your only concern would be that enabling manual switching may inhibit the auto function on the gyro. I am not sure on this part. Personally, I prefer not to have an auto function and just look at my switch position to know if my HH mode is on or not.

[Filby]

Another solution is to physically swap the switchs so that that throttle hold is in its normal position even though its assigned to another switch.

[Jermo]

Yes I know flicking the rudder stick will center the servo.
But that is not the same as flipping the switch 3 times back and forth between AVCS and Normal ( rate) mode.

I agree with David and the manual.
It is a terminology thing here.
Resetting vs recentering.

Flipping in and out of HH 3 times in less than 1 second resets the gyro and causes the gyro to "learn" the current rudder stick position as center. This is a reset.

Moving the rudder stick back and forth 3 times in less than 1 second and immediately centering the stick will return the servo to the previously learned center position. This is recentering and the servo center is gone again as soon as the heli or stick is moved.
This function is only used needed for bench testing and is the same as switching to normal mode.

This is clearly explained in the first 2 bullet points on the first page of the instruction sheet.
http://manuals.hobbico.com/fut/futm0807-manual.pdf


If you are going to use the manual as reference please don't add to it. I don't see anywhere in the manual where it states cycling between Rate and AVCS will "RESET" anything. The only difference is cycling modes allows you to memorize neutral if you have used trim in flight. Depending on how you setup your slider .ie center in rate mode for hover or center of the slider.. this setting won't change, therefore there is no need to switch modes.

The primary reason to wag the tail is to return the gyro to the neutral position. One reason you might do this is if you power up your heli and carry it to the flight line. Doing this will prevent the model from spinning to the orientation you had on the bench (this procedure comes off Futaba's website under? team tips? ).

[DavidH]

The primary reason to wag the tail is to return the gyro to the neutral position.

One more time. How does wagging the tail of the heli do anything? I have never known moving the heli to affect anything other than causing the gyro to make a correction movement.


David

[Jermo]

David, it's in the GY401 manual AND on the Futaba website. It moves the tail back to the established center position (set at power up when in AVCS mode).

So for example: let's say you power up your heli on an outside table in HH mode (as required to correctly initialize it), then carry it out to the line. If you don't do anything the heli will immediately spin to match it's orientation to where it was powered up because it thinks the wind moved it. If you cycle modes 3 times quickly OR wag the rudder 3 times quickly it will recall neutral position established at initialization AND will just happen to assume the current heading is correct.

It's just the way Futaba designed the Gyro to work. I stay in HH/AVCS mode 100% of the time but often carry my heli from the porch to the yard (especially if the ground is wet). The only time I've had an issue is when I didnt' allow proper time for the Gyro to initialze and ended up with tail drift. The only way I found to fix that was to cycle power to the gyro and re-initialize in AVCS (HH) Mode.

I know it sounds goofy but :dontknow


EDIT: and just to be clear. When I say "wag the tail" I mean move the rudder left and right quickly.

[DavidH]

EDIT: and just to be clear. When I say "wag the tail" I mean move the rudder left and right quickly.
_________________

Well maybe you should have said move the rudder stick.

I start the heli and move it out to the flight line all the time. I never do anything special. Just raise the throttle/collective and the heli starts to fly.

I have read all the instrutions about the GY gyros since I started using them back around 1996.

David

[Jermo]

so basically you just wanted to give me a hard time?

[DavidH]

Not giving you a hard time. Didn't understand what wagging the tail of the heli back and forth would have to do with the gyro. I understood it to mean moving the tail of the heli side to side. So I would think others would thought the same thing. Just because you knew what wagging the tail means to you. Doesn't mean it has the same meaning to others. Moving the rudder stick side to side quickly, I understand what that means. I would think others would also.

David

[Jermo]

hehe...ok..valid points..... :)

[Heli_harry]

Or just buy a JR G500T, Far simpler.

:D