wizard026

These DS 811 servos was purchesed with the 8103 special pack and it's not recommended to use them !! thez wont stop chatering on my Funtana 90. i use 2 DS811 on my aileron and 1 on each elevator. No problem with HiTec 5645 on my rudder and JR 537 on throttle. Whats wrong with DS 811 ?? i was trying different receiver like 700 (PPM), 770 (SPCM) and 649 (SPCM) and the same problem appear on each receiver. i don't understand ??? i sended my 4 DS811 to Horizon Hobby for a check up but they return the servos and tell me that they have no problem !!! WHAT !!! i'm not crazy !! it seem that i'm not the only one to have this problem and Horizon won't fix or replace their servos !!!! OK i spend more than 5000$ since 3 years in JR products and when you have a problem with "cheaper" servos who cost around 40 box, you stay with your problems !!! this is the customer service i have... whell, i know what to do next time...

Ben

BarracudaHockey

My Feedback: (11)

Not sure about JR's part numbers but if they are digital they are going to chatter. They all do it.

Ed_Moorman

My Feedback: (1)

JR digital servos are set for 0 deadband as far as I can tell. Hitechs have a wider deadband. They are just about guaranteed to chatter in the middle. They center really well like this. With even the slightest load they will quit. Try just lightly touching the surface. The 811s are excellent servos. Don't worry about it.

I have been flying JR since the 1980s and all the coreless and digitals I have chatter around the middle.

BarracudaHockey

My Feedback: (11)

Hey Ed!

Just wanted to take a second to tell you I enjoy your writing, keep up the good work!
Andy

dirtybird

My Feedback: (5)

My measurements of the 811 with the Vespa Servocycler show the deadband at 3us. The 8411 has 0us deadband but not the 811. I think the poster has a slight binding in his linkage or hinges. I would worry about it. It will cause high current drain and could cause premature failure of the its plastic gears and potentiometer. Its his airplane so he can do what he wants, though

bipeaddict

I agree with DirtyBird. The installation must be bind free. Since going with digitals I use Robart hinge points exclusively. No more CA hinges. In addition, I use ball links. These two things should eliminate the chatter from binding. It might not eliminate the hum from the digitals trying to center. The sound is different between the two.

bentgear

dirtybird, just wondering how many 811's you checked? The zero deadband and only having one bearing has been the blame for this problem "with this servo" for some time now. I have several of them, some do it, some don't. The funny part is the ones that do it hooked with short rods to an elevator or aileron (free non-binding surfaces BTW) will function perfectly when they are moved over to a plane using a rod and tube linkage system.

Ben, you might also want to check that the servo is not tightened down too much with the mounting screws or is not wedged slightly to one side by the opening being a little small. Both of these have given me problems with the 811 in the past.

Ed M.

dirtybird

My Feedback: (5)

I have two of them. I rechecked my test results and found they had a deadband of 1us- not three. My memory is not so good these days.
All JR servos are set up too tight for my taste. I like to get several flights out of a battery charge without getting in to exotic, expensive batteries.
Also the test load curve I got on my test rig shows it takes an error signal of 120us to develop full torque on the JR811. The Hitec 5625's I have develop full torque at 100 us and that torque is quite a bit higher than the JR811. The hitecs are a better buy in my estimation even with thier wider deadband. Torque is what moves your control surface not deadband. The deadband is by definition where the servo is doing nothing

wizard026

Whel, i agree all of you guys but did you know that the chatering problem was fixed in the second generation of the DS811. Yes... now when you buy a DS811 you get the new generation and you will find it in the new 9303 transmitter kit too. my local hobby shop return a bunch of these servo's (first generation) to JR and they changed them for new one free. i don't whant to fly my Funtana 90 until i fix the problem...[>:]

malcolmm

Could someone confirm that there are new design ds811 servos available - hopefully someone from Horizon? I experienced the same extreme chattering problem on my Funtana 90, I was told it was normal by Horizon. I didn't accept this explanation, I removed the servos, replaced them with Hitec digitals (which don't chatter at all).

If there are new ds811's, I would like to send mine back to get replaced.

Thanks
Malcolm

AsiaSRC

Any packing or physical differ between Old and New DS811, at least shoppers like us can lookout for.

jimmyjoe

My Feedback: (21)

I am having the same problem with my DS811 on my Funtana.

Tx JR 9303
Rx Hitech Supreme 8 Dual Conversion
Ailerons 2x DS811
Rudder 645 MG
Elevators 645 MG
6.Volt NiMah

When I turn my Rx power switch on the ailerons start flapping to beat hell. I can stop this by moving my Tx to the right then left to stop it or touch the surface. I can move my stick all the way to the left and let it go and the ailerons will sit there and flap up and down for ever? I thought it was my rx so I bought another one. Hooked the Rx back upto the servos and damn if it not happening again. I will do a ground test w/ ant down about fifty feet and the ailerons are moving 2-3 inches and just doing goofy stuff. Have not noticed Rudder or Elev doing it, just the DS811. Starting to get pisd and probably going to Hitech 475KB on the ailerons.

Gimble Bender

My Feedback: (32)

I'm having the same problem with my Funstar. I have DS 811s on all of my flying surfaces. The elevator and rudder don't chatter too bad but the ailerons shake like a leaf!! The bad news is that my servos came with the new 9303 that I bought last week. So I don't think that they have fixed the problem yet. Anybody know for sure? [&o]

DrDeath

My Feedback: (3)

Before I go into the bad, what I will say is that Horizon Hobby stood by their product and replaced/repaired everything

I highly recommend not using these servos on a Funtana 90. I had the suggested 811s on all surfaces of my F9 last year. I sealed the gaps and did everything by the book. Both aileron servo output post sheared right after a rolling circle on the MAIDEN flight of my F9. It wasn't a pretty sight!!!! Here are pictures of the carnage!

Now, I do have them on my Hanger 9 Super Cub in the wings and I have had no problems with them. They do chatter, but that is them just trying to find center. Once you put in input they stop chattering.

For any of my planes Funtana sized and above, I will only use MG servos. Just my $.02

Lee

DrDeath

My Feedback: (3)

Forgot to show the plane. Also, both servos broke.

Gimble Bender

My Feedback: (32)

Dr Death, Did they also replace the plane or did you have to foot that bill?

DrDeath

My Feedback: (3)

Let me tell you the quick version of the story. I called up Horizon and explained what happened. Sent in the pictures you see here and sent in the servos. They had never seen servo post give up the ghost like that before. They fixed the servos, replaced the engine and sent me a new Funtana 90!! I have been flying the snot out of that plane since last year. Finally ripped the gear out a couple of weeks ago after a year of flying on a downwind dead stick. Didn't know the engine was out until I flew the plane across the field and it was almost out of airspeed. It is fixed and ready to fly.

All I can say is that I am a Horizon Hobby fan for life! The definitely did right by me.

Lee

Strawhat Mike

Slightly off-topic but just wanted to second that. Just received a replacement for a failed Saito .72. Quick response and generous adjustment. I'm a fan as well.

-- Mike

Texastbird

DrDeath, I witnessed the same exact occurance with the 811s on a funtana. Second flight, slow easy flying on both flights, no high speed or 3d type stuff, just flying around the pattern-bingo no ailerons, and a controlled crash into the brush at the edge of the field. Stripped the gears on both servos, and no one heard any flutter when it flew by. I guess a Funtana does need metal gear servos. At least if they are JRs

Imac Kiwi

One thing I have found with the JR DS811 servo is they don't like 6 volts. Especially if you are using a Nimh pack when fully charged. Apart from that they are a great servo.

Just sharing my experience with them.

Alan.