rrTV-PHOTO   New HD TV
HOME   rrTV-PHOTO   GALLERIES   MY GALLERY   HELP-FAQ
myHOME PM pmRR MEMBERS 636 ONLINE 28 EVENTS SEARCH REGISTER  START HERE
 
1 page639 viewsPOST REPLY
MTA Hobbies . Model Rectifier Corp . 3D Heli Depot

.
.
Main Discussion > A weird servo jitter with Airtronics Stylus
 
 
I3DM
rrProfessor
Location: Israel

Hello guys.
trying to help a friend solve a weird problem that we dont even know what to start thinking about.
My friend bought a used Airtonics Stylus with a 8ch PCM Rx. he got home, and installed the Rx in his machine, which has 2 airtonics non digitals for cyclic, GV1 \ 9250 for throttle, 501 \ 9253 for tail and 9450 for pitch and then it all started, this is nothing ive seen before, when corenering the right stick and letting go, all the servos would get into a severe jitter (move quick from side to side) and they wont stop until you move the sticks again.
we recharged the batts and check again - same thing. we reset the memory - same thing.

then we unplugged the Futaba servos from the Rx (left the Airtronics ones in) - and it solved it ! no more jitters, replugged Futaba digital (only one) - same thing happend again.

anyway he tried an FM Rx and the problem went away completely.
to make sure this is not a Tx \ Rx problem we tested the same combo on another friend's Stylus and it did the same !!

any idea what this is all about ? for now he'll just be flying FM...
thanks for your help.

Team pilot for Radix, Helidirect, Logictech, ThunderPower, Fromeco, Gaui
www.liorzahavi.com
02-19-2004 Over year old.
HOMEPAGE  
 
 
Harbinger
Veteran
Location: alberta

I had the same problem with mine

When i was flying the freya i was using 8411 on the collective and not using ccpm. When i got my fury i got the new updated ccpm card and 2 more 8411s. When i added more then 1 the system wouldnt run stable. It was like it was on acid. If i moved the collective slow it wouldnt show up. When i did quick flexes on the collective the servos would often reverse or not work altogether. I called airtronics they blamed the servos. I called horizon they blamed the radio. In the end i found the hitec digitals worked without a problem but i could never run the jr 8411s until i switched over to the 10x. Again i had no issues with it running airtronic servos or hitec servos and my experience was trying to use jr digitals. I might be something to do with the pulse codes but im no rocket scientist
02-19-2004 Over year old.
HOMEPAGE  
 
 
Optech
Key Veteran
Location: Vista/Oceanside, CA.

Both Airtronics and Hitec PCM systems claim to have "the worlds fastest PCM" and handle getting data to their servos a bit different than does JR or Futaba. There was an interesting thread in the "radio" forum called "homebrew receiver" or (something like that) that talks about this. They are faster systems if only marginally so.

Sounds like a classic imcompatibility problem so both Airtronics and Horizon are half correct. Its not that the "other guys equipment" is at fault, its just their equipment may not work together. I would suggest just getting all Airtronics servos. They are a little more expensive but they work fantastic.

I would bet that if you had all Futaba tail rotor digitals or all JR "super digitals" you wouldn't have a problem. The difference is these servos are capable of higher response times.

Mike

Viva La Airtronics!
02-19-2004 Over year old.
 
 
TMoore
rrProfessor
Location: Cookeville, TN

There is something else at work here. I have a couple 401/9253 combos and 94758/757 servos all mixed with 94735's and haven't experienced this one.

Terry
02-20-2004 Over year old.
HOMEPAGE  
 
 
Optech
Key Veteran
Location: Vista/Oceanside, CA.

Terry,
The 94735s aren't digital and the 9253/x758, x757s are all high rate digitals. This follows my theory that if they used all high rate digitals they might not have a problem.

On my contest birds I'm using 94751 digitals, a 94737 coreless, and only one non-Airtronics S9251 on the tail with no problems. Here, my Airtronics x751 digitals are not high rate (the Futaba 9251 is very high rate) yet I do not have the problems they describe.

Again, it looks like non-Airtronics, non-high rate digital servos may not be compatible with the faster Airtronics PCM system???? But I'm just guessing here.

This is definitely a strange problem indeed.

Mike

Viva La Airtronics!
02-20-2004 Over year old.
 
 
TMoore
rrProfessor
Location: Cookeville, TN

My suggestion would be to systematically plug everything back in one at a time until the problem appeared again. I would suspect the gyro and the gov before the servos, unless one of the servos is scotched.

Terry
02-20-2004 Over year old.
HOMEPAGE  
 
 
LUNITIC
Senior Heliman
Location: Chesapeake, VA

My Thoughts

I've been using Airtronics stuff for over a few years now and haven't had that kind of problem that couldn't be found or fixed. I got some things you might want to look and consider.

1. Sounds like the Receiver has been in a crash and the filters could be degraded or cracked.

2. Check the wiring, and loose wire going into the receiver could cause the same jitters

3. Check all the Servo wires, a wire missing the insulation is a hit magnet.

4. Check servo for possible RF hits, a bad digital servo could also cause some nasty jitters.

5. Check RX mounting, make sure the receiver is placed away from any servos and engine gear, make sure it's grounded to the chasis or insulated with foam, I use zeal gel.

6. Check the Antenna, make sure the wire isn't frayed and loose.

7. Check gyro gain, sometimes too high gain could cause the servo to jitter and look like a RF hit.

8. Check servo bearings, nuff said

9. Bottom line, check everything and look for the obvious

If all fail then you could send the Receiver back to Airtronics and they will test it for you. In most cases if the RX is off and out of "CATAWOMBA" they will calibrate it for you at no addition cost. I have been in the same mess as you and had a bad filter, they fixed it and all I paid was shipping.
02-20-2004 Over year old.
 
 
Jim C
Veteran
Location: Indiana, PA

buy futaba will not have those probs.. hehehe

http://jimsrc.com
02-20-2004 Over year old.
HOMEPAGE  
 
 
TMoore
rrProfessor
Location: Cookeville, TN

Quote 
buy futaba will not have those probs.. hehehe


Jim,

You'll just have different ones, not necessarily the ones here.

Terry
02-21-2004 Over year old.
HOMEPAGE  
 
 
nivlek
rrProfessor
Location: Norfolk England

My father bought Hitec digitals to use with a JR SPCM reciever and
had numerous problems.After a few minutes the servos began random twitching, followed by large uncomanded movements and then sometimes refusing to move at all.The sevos were replaced for alternatives by the model shop they came from, and then returned to the importer who found no fault with the servos.The replacement servos where also Hitec but not digital , and these all work perfectly.I also have friends who use Hitec digitals with Futaba radio and these all work without problem.
02-21-2004 Over year old.
 
 
z11355
rrMaster
Location: 10000 is enough time wasted.

another incompatibility is JR4131/8101 w/ Fut.
149DP RX's. They get into a weird power-on
stutter that stops once you move the sticks
02-21-2004 Over year old.
HOMEPAGE  
 
 
1 page639 viewsPOST REPLY
JR-Spektrum . Gyro Hobbies . E-flite

.
.
Main Discussion > A weird servo jitter with Airtronics Stylus
  UPDATE SCREEN   PRINT TOPIC Advertisers 

Subscribe to This Topic

Tuesday, October 7 - 3:11 pm - Copyright © 2000 - 2008 runryder.com | email | link to rr | runryder needs cookie