GY 401 broken?

[BarnOwl]

After deciding to give my T-rex 600 a good spring overhaul I encountered a gyro problem I cannot explain:

I took the complete heli apart. When everything was put together again I re- binded my DX7 and everything worked fine except for the GY 401.
After initialisation the slow blinking light stays on, indicating the gyro recieves "no rudder input".

Now, before posting here I did a thorough internet search on the issue and everywhere this same issue turned up it was mostly a matter of wrong setup/initialisation.
However I checked everything before posting here:

TX setup: Nothing changed, Gear in Gyro auto mode with 72% HH and 50% rate. Using HH in all flight modes. (I did try other settings even starting from scratch with the gyro to no avail)

Checked the servo/gyro/rx connections for rudder and gear over and over.

The rudder input is working, the gyro is working but the damn light keeps flashing.
I have not flown the heli yet to see what happens but something is wrong and I cannot put my finger on it.

So far my conclusion is either the gyro is shot or I overlook something badly.

Any suggestions/comments truly appreciated........:)

[BarracudaHockey]

Make sure its in heading hold and rebind. Its probably booting before the reciever. This sets the fail safe to heading hold, which is what the reciever will send out until it connects.

[BarnOwl]

Thanks, Andy,

I did that a couple of times but no luck.

Anyway, the gyro is shot! I ripped another 401 from one of my other heli's and it worked like a charm as soon as it was connected with the same settings. So conclusion: 401 busted!
Maybe a crash I had last week was the cause for this. Nevermind, the bird is flying again!

Time to upgrade to the Spartan 760! ;)

[JEB123]

I'm having the same problem, but my 401 is brand new! What gives?

[BarnOwl]

With a brandnew one I would'nt jump to conclusions too soon. There are a hundred possible reasons for a slow blinking light on the 401.
The only way to be 100% sure is to swap the gyro with another one on a similar setup heli and see what happens.

[LITHIUMSTATIC]

I put a 401 I had laying around on my Compass Knight 600E today and after setting everything up (exactly like another 401 that was on the same bird) it was waging faster than a dogs tail and drifting right. It also was kicking too. The only difference was the mounting location. I'm going to move it to a new location tomorrow.

[HeliSmith]

Jeb,

If you are having problems with it call Nikki @ 818 348 4354. I will test the gyro if you wish too. If you wish me to test it tell Nikki I offered to do so.

One thing I want to mention is with the DX6i make sure you have no rudder trim when you bind. Actually we don't use rudder trim ever with the 401 and I go to lengths to make sure not to have subtrim as well but that is a different topic.

Mike

[JEB123]

Got it working, edited my post above.
Thanks Mike
Jorge

[JEB123]

Sounds like you know what you're doing, but I had the same problem with my DX6i and I followed this post to the letter and it fixed it. Might be different with the DX7, but worth a try. See Matt155's reply in the link. Hope this helps...

http://www.helifreak.com/showthread.php?t=75541

[HeliSmith]

Glad to hear you got it. Gyros can be such a pain to setup but once you learn the 401 it starts to be a snap.

[JEB123]

Just like anything else in life that's worth doing, right? Thanks to all of you for your time. Keep'em flying!:cheers

[vboy55]

im haveing and issue with my 401 its going into hh but it drifts to the left no matter what % im at 72 84 100 it still drifts to the left i have cleared out the radio and reentered all the settings and its doing the same thing could it be broke? :arggg:

it is on a raptor 30

thanks for the help

[LITHIUMSTATIC]

im haveing and issue with my 401 its going into hh but it drifts to the left no matter what % im at 72 84 100 it still drifts to the left i have cleared out the radio and reentered all the settings and its doing the same thing could it be broke? :arggg:

it is on a raptor 30

thanks for the help

Contact Wayne brown on here. He told me how to reset mine and it the very same problem your having.

[vboy55]

Sure thing, however I'll ask you to post this entire message in the main forum to help others with the drift.

To reset the 401 gyro's neutral position you need to either have A) the gain switch set for both rate and HH, or B) be able to move the rudder stick rapidly full left/ full right in 1-2 seconds.
Here's the process:
Power up the tx, followed by the Rx. Wait until the gyro initializes and rapidly flip the gain switch 5-6 times as fast as you can, or use option B and go full left and right 5-6 times as fast as you can.
At this point the light on the gyro will blink, then reset to HH if you left the switch in the hh position, and this resets neutral.
If you are flying Spektrum, this is a good chance to re-bind with a twist.
Spektrum receivers utilize the failsafe settings to feed a signal to all servos and the gyro during the moments pause between the gyro initializing and the power up of the receiver. Rebinding will correct the zero point of the gyro signal, and You have the option to 'correct' a few things usually overlooked during the bind process.
During the 2 or so seconds between turning on the tx, and it actually transmitting the bind signal, you need to go to mid-stick on the collective, throttle hold ON, HH ON, and all trims and sticks at the normal position for flight.
Once bound, the failsafe signal will be for HH on, Throttle Hold ON, level swash and zero pitch.
As the Futaba, Logitech, and JR gyros initialize BEFORE the receiver sends signal, the failsafe settings will be loaded, and your drift should be gone every time.
One other idiosyncrasy others and I have noted is that if there is enough time between use, the signal gets fouled up, so the first flight of the weekend should be power up tx, then rx and allow to boot. Turn off rx and turn immediately back on. This appears to also help in the initialization of the gyro at neutral, and is relatively painless to do.
Good luck with this issue!



Quote:
Originally Posted by vboy55
wayne

one of the other guys on here said you mite be able to help me my 401 keeps drifting to the left i have reset everything in the radio and reset up the tail and i keep getting the same thing LITHIUMSTATIC said he had the same problem and you reset the gyro can you help me out?


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