FlyingFish

My Feedback: (17)

I have two corona 120 Helicopters, both are set up exactly the same with Mega 16/15/3 brushless motors, both have 3 cell 2100 mAh 11.1 volt Lipo batteries, both have Pheonix 35 Speed controls, and Both have brand new Airtronics VG400 4 channel radios, both have their antennas mounted in the same spot in the same way AND BOTH use Frequency #26, BUT, one helicopter flies fine and the other Helicopter gets lots of glitches and is very sensitive when you move the Rx anttenna around.

What is the reason that one heli gets glitches but the other don't, with identical set-ups ???????????[&:]

rcflyertim

Well... one explanations may be that there is a short in the antenna wire, or somewhere on the surface mounted hardware (electronics) you have a small crack in a circuit. I have two 120's and both of them run a little different. I would try taking the electronics out of the one that glitches and swapping them out. If this process of elimination works then you will have your answer. If not, the only explanations I can give is the resistor on the motor may be bad

FlyingFish

My Feedback: (17)

Well, I already swap the Bad Heli with another Radio and I'm still getting the High sensitivity with radio glitching. At First I had an Airtronics VG400 on #33 Frequency on the bad heli, But My other heli worked fine on #26 Frequency, So I figured something in the area was picking up on the #33 Freq. and interferring with it. So, since I never had any trouble with my other heli on the #26 Freq Radio, I decided to Put a #26 Freq. Radio in the bad heli. But I still got the same glitch problem on the same heli.

Is it Possible that a Bad brushless motor or bad speed control can be the blame even if the glitch occurs while the heli is NOT RUNNING? ( I get the glitching even when the motor is just sitting there not in motion)

This "Bad Heli" Worked fine for about 18 months with no problems, suddenly theirs glitching and radio interferrence! The only thing that has NOT been replaced in the 18 months are the brushless motor & ESC, it's the only thing left to suspect![X(]

TIA

A dirty servo pot somewhere?

FlyingFish

My Feedback: (17)

Here's a small clue I left out that may be of importance in diagnosing the glitch; Upon closer observation I'm seeing that 2 of the 3 servos "PULSE", which means that exactly every 3 seconds the servos twitch at a steady uniform rate even when a glitch is not actively affecting the radio system. The Tx & Rx are new, but the servos are old, Could that be the problem ?, Reno, this could have something to do with your dirty servo pot theory! [&:] The glitching seems more active when the heli is on the ground and I walk up close to the heli, but during flight it dosn't seem to affect control of the heli, but I don't like any kind of glitch, it gives me the horrors. I'm just affraid the dam thing is gonna fly off and hurt someone!

FlyingFish

My Feedback: (17)

I don't think it's the Pheonix 35 ESC, because I disconnected it and connected a seperate Rx Battery pack to the reciver and I still get glitches, Now the radio is working independent of the heli's electrical system and I'm still getting glitches! next I'm going to remove the whole radio systems, servos and all, and keep it away from my heli and see if i still get glitches without the heli being involved at all, if so then it must be bad servos! any thoughts?

[&:][&o]

FlyingFish

My Feedback: (17)

Okay Guys, I found the problem, but I'm not out of the woods yet..............

I still need your help in making a decission.


Here are my findings;
All servos work perfect with the new Tx & Rx, under one condition, So long as I don't hook up the gyro the Airtronics VG400 radio works perfect with not even one glitch, But as soon as I install the Gyro between the Rudder servo and the Rx rudder channel, the whole radio goes crazy!!! All the servos twitch and my ESC runs the motor on and off erratically.

Here are my 3 questions,

1) Can it still be a bad RUDDER servo, although the RUDDER servo works perfectly normal when plugged into the rudder channel alone ???

2) Is my brand new JR G410T Basic Tail Lock / Rate Gyro Defective

3) Or is it possible that the gyro is set to sensitive and causing havoc on the rest of the system?
Can I adust something to clear the glitches, or just dump the Gyro, it's only 2 months old, brand new out of the box from helihobby.com
My other corona has the same gyro and it works perfect, but Im not taking that one apart to experement.

Any opinions are welcomed.............

beaner

Hey FlyingFish,
Are you using a digital or analog servo for rudder?

Beaner

FlyingFish

My Feedback: (17)

Not sure what kind of servo it is, this servo came with the heli when I purchased it on ebay 2 years ago, its an EXPERT SL300 Micro BB servo.

which servo is better for the G410 gyro, anolog or digital?

FlyingFish

My Feedback: (17)

I have ordered a brand new gyro and a brand new rudder servo, let's see which component is at fault, I say it's the gyro. I'll let you know as soon as helihobby delivers the stuff and I test it. But which ever component is at fault, I will probably Keep both, I can use a new rudder servo anyway.
[8D]

beaner

FlyingFish,
The reason I ask is that I have a G410 too (as well as 2 G500t's). I tried to use a digital tail servo. My whole system was glitchin' and twichin'. Thinking it was noise being generated by the servo effecting my receiver, I bought a PPM receiver, same problem. Went back to the JR810 servo, glitching gone. I guess that while the digital servos have many good attributes, they also draw huge amounts of power and generate some noise. I read somewhere that putting a 47uf capacitor across the positive and ground leads (at the servo) will eliminate the twiching, but i never tried it.

I also had a similar problem with the 410 after a crash. I replaced the gyro, glitching gone. I hope you get the problem fixed, because I know how annoying those pesky glitches can be especially when they come and go.

Beaner

FlyingFish

My Feedback: (17)

Thanks Beaner, I'll keep you guys posted on my findings as soon as the parts get here, about 3 - 5 days.

FlyingFish

My Feedback: (17)

Got the helihobby parts, below are the parts I ordered to trace the glitch problem!

PARTS LIST
1) New G410 Gyro
1) New JR NES-331 Servo
3) Glitch reducers

Here are my findings below;

New Gyro + New Servo = tiny rudder servo glitch

Old Gyro + New Servo = tiny rudder servo glitch

Old Gyro + Glitch Reducer + New Servo = OKAY (no glitches)

Old Servo + New Gyro = Bad Glitches

Old Servo + Old Gyro = Very Bad Glitches

It's seems that the problem was solved by changing the rudder servo and adding a glitch reducer between the gyro and rudder servo, but I'd like to range test this heli for a few days before I declare success, I still dont trust any of this set up !!!!!!!
Looks like anytime the old servo was involved in the various combinations is when the problem was at it's worse, but I still need some time to confirm this to be true, a nice outdoor range test should let me know the truth!

beaner

Hey FlyingFish,

Thanks for the follow-up, very methodical testing on your part! But that’s what it takes to troubleshoot glitching. Looks like it was the servo, glad you got it solved.

Beaner

FlyingFish

My Feedback: (17)

Seems that after a couple of test flights, the tiny glitch in the rudder servo is back again, it's not affecting the control of the helicopter and as of now I still don't have anymore glitches in the other servos or the ESC. So long as the set-up stays that way and dosn't get worse I can at least use the heli. But I still can't understand why even when I tried a New Servo, plugged into a new Gyro, connected to a new receiver would make any glitch at all......! All components are compatable, I got the same exact set up on my other Corona with no glitches or problems......[&:]

Must be Gremlins in my heli..........[:@]

FlyingFish

My Feedback: (17)

So far so good, 4th flight already without incident. Me shall officially declare the problem solved !
(IT WAS A BAD RUDDER SERVO SENDING FALSE SIGNALS TO THE REST OF THE OTHER SERVOS OR Rx)..........

Lesson learned, I think we guys should dump any servo over 5 years old or sooner just to be on the safe side.....[&:]
If you have a model car with a bad servo, who cares, but anything that flys should be saftey checked and over hauled after a certain amount of hours, days or months, kind of like the way commercial airlines do. (if its affordable) Sometimes the airlines don't even do what their suppose to do, but saftey comes first in my little fleet........[X(]

ufoman

I noticed a lot of flyers on other sites use ferrite rings on their esc controllers in addition to glitch reducers to cancel the effects from the motor and esc noise. I ordered this one from FXaeromodels. Most electronic products have some kind of inductor up front in the circuit so it should help out. Also the glitch reducer from HeliHobby....the manufacturer doesn't recommend using on digital servos from what I hear.

http://www.fxaeromodels.com/product_...roducts_id=380

FlyingFish

My Feedback: (17)

So far eveything is working okay, if I still get glitches in the future I can always add ferrite rings as well, Thanks for that website link. My glitch reducers are working fine so far, Im not using digital servos, my replacement rudder servo is analog.