Fun, Learning, Friendship and Mutual Respect
START  HERE


Unregistered
Go Back   HeliFreak > R/C Helicopter Support > 450 Class Electric Helicopters


450 Class Electric Helicopters 450 Class Electric Helicopters manufactured by Align, Tarot, SYMA, Airhog, Chaos, HK and similar.


Reply
 
Thread Tools Display Modes
Old 08-12-2007, 10:11 PM   #1
Rush
Registered Users
 

Join Date: May 2007
Location: Philippines
Angry JR G500T Gyro

Has anyone gotten the JR G500T gyro to work with a furaba 9C super? Its a crazy gyro but i hear its supposed to work better than a 401.. if you can get it setup that is.... working on it for a couple of weeks till i got so frustrated i went and bought a 401
Rush is offline        Reply With Quote
Old 08-12-2007, 10:41 PM   #2
JKos
Registered Users
 

Join Date: May 2005
Location: Redondo Beach, CA
Default

Rush,
What exactly is the gyro doing? There are only two differences in setup of the G500T compared to the GY401. 1) The gyro does not have an LED to tell you when it is in HH mode (but it is obvious based on tails response to inputs). 2) You must use subtrim on the rudder channel to cancel out any drift while in HH mode.

That's it. Everything else about setup is the same.

- John
JKos is offline        Reply With Quote
Old 08-12-2007, 11:16 PM   #3
Rush
Registered Users
Thread Starter Thread Starter
 

Join Date: May 2007
Location: Philippines
Default

Quote:
Originally Posted by JKos View Post
Rush,
What exactly is the gyro doing? There are only two differences in setup of the G500T compared to the GY401. 1) The gyro does not have an LED to tell you when it is in HH mode (but it is obvious based on tails response to inputs). 2) You must use subtrim on the rudder channel to cancel out any drift while in HH mode.

That's it. Everything else about setup is the same.

- John
as soon as i lift off, it piro's. I did exactly that. put it in Std rate mode to center the rudder. then put it into avcs mode. used subtrim to straighten the rudder servo in HH mode. cant make it work now. just piro's...

Got so irritated with it.. took it off and put a 401 in it. surprisingly, there's very little info on setting that thing up for a futaba 9C. like how much gain in avcs mode is expected?

There are two switches on it that are marked 1 and 2? what are they for? not sure which is reverse and hi res?
Rush is offline        Reply With Quote
Old 08-13-2007, 03:10 AM   #4
T-wreck450
Registered Users
 

Join Date: Jun 2007
Location: Texas
Default

Had same gyro on my 450 with DX7. Had similar problem. Couldn't ever really fix it but if you do please fill me in. I also gave up and got a 401.
T-wreck450 is offline        Reply With Quote
Old 08-13-2007, 03:40 AM   #5
Rush
Registered Users
Thread Starter Thread Starter
 

Join Date: May 2007
Location: Philippines
Default

for a $150 gyro.. you'd think JR would have better customer support on it. the only thing i got with it was the Horizon Hobby manual which was very similar to the one with the telebee 6g.

I put the 6g on the trex and i even got that to fly. not well but it could hover.
Rush is offline        Reply With Quote
Old 08-13-2007, 08:40 AM   #6
JKos
Registered Users
 

Join Date: May 2005
Location: Redondo Beach, CA
Default

> as soon as i lift off, it piro's.

Sounds like the gyro sense is reversed. Did you ensure it is set correctly? As well as your control input resulting in correct tail movement?

> There are two switches on it that are marked 1 and 2? what are they for? not sure which is reverse and hi res?

There should be a label above the switches. Otherwise, it's in the manual.

- John
JKos is offline        Reply With Quote
Old 08-13-2007, 09:49 AM   #7
jschenck
Registered Users
 
Posts: 302
 
My HF Map location
Join Date: Jun 2006
Location: La Vista, NE.
Default

The top switch is for reversing the sense.

I agree the manual is weak, but it does spell out the basic setup. I have two of the 500T's and they work well for me.

http://www.horizonhobby.com/ProdInfo...00t-manual.pdf
__________________
Team Grand RC
jschenck is offline        Reply With Quote
Old 08-13-2007, 10:55 AM   #8
BarracudaHockey
Registered Users
 
Posts: 6,363
 
My HF Map location
Join Date: Jan 2005
Location: Jacksonville FL
Default

Sounds like the gyro was reversed.

You dont use sub trim to center the servo.

Set the gyro in AVCS mode, turn the gain all the way up (Gyro Sens menu, mode=GY, mix to act, rate up to AVC100)

Use the rudder sub trim to stop the slider from drifting.

Set the gain back to avc 40 or so.

Give right rudder, the servo should pull the rod, if thats wrong your rudder channel is reversed.

Pick up the heli and turn the nose to the left, the rudder should again, pull the rod, if thats wrong reverse the gyro by the dip switch.
__________________
Andy
AMA 77227
Jacksonville FL

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
BarracudaHockey is offline        Reply With Quote
Old 08-13-2007, 12:34 PM   #9
Rush
Registered Users
Thread Starter Thread Starter
 

Join Date: May 2007
Location: Philippines
Default

Thanks all...

Barracuda.. those are even better instructions than what came with the manual. let me try that. Thanks lots.

Did you guys do anything on the end points or set expo?

Thanks again.
Rush is offline        Reply With Quote
Old 08-13-2007, 01:46 PM   #10
BarracudaHockey
Registered Users
 
Posts: 6,363
 
My HF Map location
Join Date: Jan 2005
Location: Jacksonville FL
Default

Quote:
Originally Posted by Rush View Post
Thanks all...

Barracuda.. those are even better instructions than what came with the manual. let me try that. Thanks lots.

Did you guys do anything on the end points or set expo?

Thanks again.
End points should be 100/100 on the rudder channel and 100/100 on channel 5 when using the gyro sens screen. If your piro rate isnt what you want then crank up the end points, try it 5 percent at a time or so.

EXPO is a matter of personal preference. Try it and see, it wont effect the gyro at all.
__________________
Andy
AMA 77227
Jacksonville FL

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.
BarracudaHockey is offline        Reply With Quote
Old 08-13-2007, 02:05 PM   #11
mporlier
Registered Users
 
Posts: 662
 
My HF Map location
Join Date: Sep 2006
Location: Boucherville, Canada
Default

Also, did you re built your tail? maybe the tail rotor belt is reversed. It did happen to me once.
__________________

To view links or images in signatures your post count must be 0 or greater. You currently have 0 posts.

T-Rex600N Pro
X9303/R921
Spartan Ds760 Gyro (love it)
[
mporlier is offline        Reply With Quote
Old 08-13-2007, 02:51 PM   #12
Mike_117
Registered Users
 
My HF Map location
Join Date: Jan 2007
Location: Kansas
Default

I have a 500T and ds3900g programmed with a dx6 radio

It took a while to set this gyro up. Finally, I set everything to zero except the gryo gain.
For HH mode ranges from +20-35% to keep the tail from shaking..

Rate mode is around -35%

NO subtrims for rudder or channel 5..

I had to get the mechanical zero perfect by moving the tail servo back and forth until the drift stopped. (you could also adjust the linkage to fine tune it in.)

Make sure everything for the tail on the TX, ie subtrims for Rudder and channel 5 is zero.

Make sure the trim tabs on the TX are zero below the stick..

and like the mporlier said.. make sure the tail is turning up.. leading edge foward.. If it spins down when closest to the front you need to flip the belt so it does spin up..that will definately make it piro out of control..
Mike_117 is offline        Reply With Quote
Old 08-13-2007, 03:06 PM   #13
JKos
Registered Users
 

Join Date: May 2005
Location: Redondo Beach, CA
Default

> Make sure everything for the tail on the TX, ie subtrims for Rudder and channel 5 is zero.
> Make sure the trim tabs on the TX are zero below the stick..

This is where the G500T (and all other JR gyros for that matter except the new G770T) differs from the Futaba gyros. With JR gyros, they do not learn what neutral rudder is at power up. You must almost always use subtrim to cancel out drift in HH mode on JR gyros. That's just how it works. You must match the neutral pulse width of the rudder channel to what the gyro is preprogrammed to as neutral.

- John
JKos is offline        Reply With Quote
Old 08-14-2007, 08:04 AM   #14
Rush
Registered Users
Thread Starter Thread Starter
 

Join Date: May 2007
Location: Philippines
Default

Quote:
Originally Posted by JKos View Post
> Make sure everything for the tail on the TX, ie subtrims for Rudder and channel 5 is zero.
> Make sure the trim tabs on the TX are zero below the stick..

This is where the G500T (and all other JR gyros for that matter except the new G770T) differs from the Futaba gyros. With JR gyros, they do not learn what neutral rudder is at power up. You must almost always use subtrim to cancel out drift in HH mode on JR gyros. That's just how it works. You must match the neutral pulse width of the rudder channel to what the gyro is preprogrammed to as neutral.

- John
does that mean you have to do it everytime you power up the gyro? or only on setup? I hope only on the setup.. that could be intense otherwise for a gyro.

I had it setup before ok. more by luck i think. I had to rebuild the tail as i'd twisted the tail shaft but the rotor turns into the downwash. after the rebuild.. constant piro. Ijust thought it was wasted and bought a 401...

I'll try it again with all your input. thanks heaps!

Regards
Rush is offline        Reply With Quote
Old 08-14-2007, 08:45 AM   #15
JKos
Registered Users
 

Join Date: May 2005
Location: Redondo Beach, CA
Default

> does that mean you have to do it everytime you power up the gyro? or only on setup?

Usually only during setup. Cranking up the gain during setup helps you fine tune the subtrim. Then back the gain down to normal.

> I hope only on the setup.. that could be intense otherwise for a gyro.

The error caused by this adjustment isn't a piro but rather a slow drift.

- John
JKos is offline        Reply With Quote
Old 09-27-2008, 11:03 AM   #16
Clarkson
Registered Users
 

Join Date: Jun 2008
Default

I just put in a 500T in my b400.. seems to be doing ok, but its performance seems to change daily. ( new to this) the instructions say " set the Gyro to rate mode as described above" and it is NOT described above, or anywhere. When I first put it in , it was dead on... really great, it seems to be wandering a bit now, and I am playing with the gain.
Defined setup instructions would be great. I am really disapointed in ALL instruction manuals, although E flite is an improvement over some others. Too many assume that the buyers are knowlegable in basics.
Rich
Clarkson is offline        Reply With Quote
Old 09-27-2008, 12:09 PM   #17
Clarkson
Registered Users
 

Join Date: Jun 2008
Default

Can anyone tell me WHAT ( on the switches on the 500 Gyro) mean. The REVERSE thing I cn figure out :-) but what is HIGH and STANDARD rate ? and how do I access the the different rate modes ? The instructions say " set the G500T to the Rate Mode position as explained above" and there is NO " above" or further instructions.
Clarkson is offline        Reply With Quote
Old 09-28-2008, 10:59 PM   #18
jschenck
Registered Users
 
Posts: 302
 
My HF Map location
Join Date: Jun 2006
Location: La Vista, NE.
Default

Quote:
but what is HIGH and STANDARD rate ?
Standard frame rate servo vs. high frame rate servo. This is the same as the "DS" mode on 401's. Flip it to high frame rate servos such as Futaba 9254, JR 8700, and JR 810T. Use "standard" for servo's such as a Hitec HS525 and such. Futaba calls it digital mode but it's really a higher frame rate signal. Just that most digital servo's can handle the higher frame rate. the JR 8700 and 810 are actually analog servos capable of high frame rate.
__________________
Team Grand RC
jschenck is offline        Reply With Quote
Old 09-28-2008, 11:05 PM   #19
jschenck
Registered Users
 
Posts: 302
 
My HF Map location
Join Date: Jun 2006
Location: La Vista, NE.
Default

reading your post again I think I need to say: the "Standard" and "High" have nothing to do with the gain, they are for signal frequency to the servo.

Select rate mode by going below 50% on your gain (on 0-100 setup that's 50, on -100 to 100 that's 0). I have found that gyro's work better if you get them close to no drift in hover in rate mode which is what the previous posts were refering to. You can't do that effectivly with a 401 or JR500 on some heli's such as the Trex-450 or you'll really limit the amount of throw your tail gets.
__________________
Team Grand RC
jschenck is offline        Reply With Quote
Old 09-29-2008, 09:12 AM   #20
Clarkson
Registered Users
 

Join Date: Jun 2008
Default

Thanks.. after posting my last query, I went back and re read the prior posts and got some idea of things. It IS confusing, when "High " and "normal" rates on the Gyro do NOT refer in any way to Rate and Heading Hold... sheesh. Talk about confusing terms.

The 500T also says to apply the GAIN to min 90%, but if tail wag is still seen, to move the rudder linkage IN a hole on the servo. I am down to almost a direct connection, and still get wag. I have reduced gain to 60%, and still get some wag. The Gyro literature does NOT recommend going below 90% gain, or the whole point of spending some bucks on this Gyro is lost. Anyway, I will try it on HIGH rate ( GYro switch) and play with the gain again. At this point, the original E flite HH gyro was pretty good. Yes, I have a JR DS 290G Ultra speed servo aboard for the rudder.
Thanks for the assistance
Rich
Clarkson is offline        Reply With Quote
Reply




Unregistered
Go Back   HeliFreak > R/C Helicopter Support > 450 Class Electric Helicopters


450 Class Electric Helicopters 450 Class Electric Helicopters manufactured by Align, Tarot, SYMA, Airhog, Chaos, HK and similar.

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


Copyright © 2004-2011 - William James - Helifreak.com