RC Radios, Transmitters, Receivers, Servos, gyros Discussion all about rc radios, transmitters, receivers, servos, etc.

jittery servos, strange problem

Reply

Old 05-01-2018, 07:25 PM
  #1  
kiwiremote
Junior Member
Thread Starter
 
Join Date: Apr 2018
Posts: 15
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default jittery servos, strange problem

I have a rc sailboat using a futaba 29 MHz radio and the servos are constantly jittering when the transmitter is not really close(a couple of meters, the range of transmitter is over 160 meters) but if I turn the transmitter off the servos stop jittering so I am confused as to what this means and where the problem might lies.
kiwiremote is offline  
Reply With Quote
Old 05-01-2018, 10:30 PM
  #2  
kiwiremote
Junior Member
Thread Starter
 
Join Date: Apr 2018
Posts: 15
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

What really confuses me is that the jitter goes away when the transmitter is close, otherwise I would consider dirty pot inside the servo or the transmitter.
kiwiremote is offline  
Reply With Quote
Old 05-02-2018, 05:07 PM
  #3  
grotto2
My Feedback: (2)
 
grotto2's Avatar
 
Join Date: Feb 2003
Location: Palm Bay, FL
Posts: 1,043
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

How is the antenna routed? Away from the servos? Near any other electrics? Near any static sources such as metal parts that could be rattling in the wind?

Last edited by grotto2; 05-02-2018 at 05:09 PM. Reason: spelling
grotto2 is offline  
Reply With Quote
Old 05-03-2018, 09:57 PM
  #4  
kiwiremote
Junior Member
Thread Starter
 
Join Date: Apr 2018
Posts: 15
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Yes it is not in danger of any of those things you suggested and my testing is on dry land inside my house.
kiwiremote is offline  
Reply With Quote
Old 05-04-2018, 05:07 AM
  #5  
Jesse Open
 
Join Date: Mar 2018
Location: Just North of Canadian border
Posts: 1,200
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Have you tried it outdoors with a simple range test?
Under the right conditions, there may be some interference generated inside your house. When mixed with the signal from your transmitter the procucts result in the jittering you see.

Try a collapsed antenna range test out in the open. Very likely all is well.
Jesse Open is online now  
Reply With Quote
Old 05-04-2018, 06:40 AM
  #6  
grotto2
My Feedback: (2)
 
grotto2's Avatar
 
Join Date: Feb 2003
Location: Palm Bay, FL
Posts: 1,043
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Jesse Open has a point. I've seen fluorescent lights drive a radio crazy!
grotto2 is offline  
Reply With Quote
Old 05-04-2018, 01:20 PM
  #7  
kiwiremote
Junior Member
Thread Starter
 
Join Date: Apr 2018
Posts: 15
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

Tried the open range test, no different. Also I see no interfering signals on my sdr which lets me look at all the radio signals on my computer screen. At this point I will have to try swapping different components in and out of the system to try and track down where the problem originates, I had just hoped to narrow things down with theory before trying this but that doesn't look like it is going to happen so on with the task.
kiwiremote is offline  
Reply With Quote
Old 05-04-2018, 05:31 PM
  #8  
mongo
My Feedback: (14)
 
mongo's Avatar
 
Join Date: Dec 2001
Location: Midland, TX
Posts: 2,659
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

what is your rx power system. i have seen over voltage symptoms like described in the past on those 29 mhz systems.
mongo is online now  
Reply With Quote
Old 05-04-2018, 08:17 PM
  #9  
grotto2
My Feedback: (2)
 
grotto2's Avatar
 
Join Date: Feb 2003
Location: Palm Bay, FL
Posts: 1,043
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

The receiver may simply need a good tune-up.
grotto2 is offline  
Reply With Quote
Old 05-05-2018, 01:35 AM
  #10  
kiwiremote
Junior Member
Thread Starter
 
Join Date: Apr 2018
Posts: 15
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default

I am using 4 aa 1.2 volt nimh batteries for the power which I actually worried might be too low as the receiver is a bec type. The whole rc system is quite old, it is what came with the 2ndhand boat, I have installed a new electrolytic capacitor in the receiver but that made no difference to the problem.
kiwiremote is offline  
Reply With Quote

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


Thread Tools
Search this Thread

Contact Us Archive Advertising Cookie Policy Privacy Statement Terms of Service