JR Radio & Spektrum Radios Discuss all your JR and Spektrum gear.

ds811 and gws jitters

Reply

Old 04-01-2004, 08:01 AM
  #1  
LShaver
Member
Thread Starter
My Feedback: (2)
 
Join Date: Sep 2003
Location: Columbus, OH
Posts: 62
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default ds811 and gws jitters

Hello Dannny, I got a new 8103 last year with 811 servos...works perfect

Problem is while test flying it in a radio rat last year I also switched out the 811,s and used new Gws servos to make sure everything worked without a problem...and it did...perfect. Now I am settting up my UCD3D 60 with 2 811's on elevator (on a Y) and tried a GWS on the rudder with bad results; every time I plug in an extension to the GWS the rudder goes crazy ( moves by itself and jitters) if I unplug the extension and plug the same servo into the rudder channel it works fine...I've switched out extensions and tried 4 differant GWS servos with the same results, the only cure was to use a 811 on the rudder...my question is this a problem with 811's and analog servos or is there a fix ( choke,filter,buffer,etc) ? I plan on using this mix in my larger scale planes if I you have a cure. P.S. I got the same results with 4.8 and 6.0 volts

TIA Doc
LShaver is offline  
Reply With Quote
Old 04-04-2004, 05:15 PM
  #2  
c016Y
Senior Member
 
c016Y's Avatar
 
Join Date: Oct 2003
Location: Tulsa, OK
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: ds811 and gws jitters

same problem here. Curious if anybody ever figured this out. DS811's on UCD .60 rudder is horrible.
c016Y is offline  
Reply With Quote
Old 04-06-2004, 01:12 PM
  #3  
dsnyder
 
dsnyder's Avatar
 
Join Date: Jun 2002
Location: Champaign, IL
Posts: 9,365
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: ds811 and gws jitters

I don't have any information on the GWS equipment, you would need to contact them for that. If the 811 does that however, it can be a number of things. It could be a bad extension, slop in the linkages or control horns, servo arm fit on the servo, servo mounted too rigidly (servo screws too tight, servo eyelets installed in the incorrect direction, servo mounting rails too tight against the servo), a dirty connection between the servo and the receiver, too high of voltage, a bad battery, switch, loose hinges, hinges that are too stiff and don't allow easy movement, any binding, etc. The 811 also is a single ball bearing servo, which means there is a small amount of play possible in the output gear, and with the centering power of the 811 it can cause some small jittering. If you can lightly touch the control surface when this is happening and it stops, it will not happen in the air due to the air loads on the surface, so it is fine to fly. If it doesn't stop, the pot may be worn in the servo.
dsnyder is offline  
Reply With Quote
Old 04-06-2004, 01:24 PM
  #4  
c016Y
Senior Member
 
c016Y's Avatar
 
Join Date: Oct 2003
Location: Tulsa, OK
Posts: 215
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: ds811 and gws jitters

It is totally caused by the play in the output gear. When I increase the throw it gets worse. When I add subtrim it goes away. It is the play in the center and it throwing it back and forth that causes the problem. Is there a digital servo that does not have play in the output gear? ie.. What kind of servos do not have this play (what to look for)? examples? Thanks for your help.

I have seen many people with this exact problem on this control surface on this plane. I think it is just not the right servo for the job. Works great on all the other control surfaces. I think this is a problem though. I have noticed the problem gets worse with time if you let it run like that. I think it is wearing it out when I fly it that way.
c016Y is offline  
Reply With Quote
Old 04-06-2004, 01:30 PM
  #5  
dsnyder
 
dsnyder's Avatar
 
Join Date: Jun 2002
Location: Champaign, IL
Posts: 9,365
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: ds811 and gws jitters

It isn't a problem to fly it if it stops when you lightly touch the surface. Servos that do not have the play in the output gear are dual bearing servos, which are higher end servos, such as the 8101, 8231, 8411, 8611, etc.
dsnyder is offline  
Reply With Quote
Old 04-09-2004, 07:15 PM
  #6  
LShaver
Member
Thread Starter
My Feedback: (2)
 
Join Date: Sep 2003
Location: Columbus, OH
Posts: 62
Gallery
My Gallery
Models
My Models
Ratings
My Feedback
Default RE: ds811 and gws jitters

OK ...I found the problem...had to use a h/d ext (20) on the GWS and all jitters and such went away at 4.8 and 6.0 volts...I'm not flaming GWS servos cause they worked like a champ in the radio rat and the price is great ....I guess to have piece of mind it cost ya so I put in a 8101 on the rudder...thanks for the feedback guys Doc
LShaver 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