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Old 03-23-2008, 05:25 AM   #1
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Exclamation my servo is glitching at certain speeds, any help is appreciated :)

Hi,

I've been trying to solve the servo glitching issue for some time now but I couldn't figure out the problem.
I have a vfs-1 esc with a capacitor 3300uf on it, a marc rheinard 10t motor with vfs's ultimate shotki diode, and a micro receiver for the m11. When I start throttling up, everything works well, but at certain frequencies the servo glitches like crazy. When I throttle up fully (max speed) the glitching stops, when I reduce the speed a little, the glitching comes back. I tried adding a separate battery for the receiver but it also didn't help.

Any suggestions are truly appreciated.
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Old 03-23-2008, 06:34 AM   #2
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Since it only happens at partial throttle, (not at initial throttle up when the current draw is greatest) it sure sounds like the speedo's switching frequency is causing interference with the radio. I would try moving the Rx antenna around, move the Rx away from the speedo, and try re-routing the servo wire, especially if the wires are all bundled (zip tied) together. Can you change the channel that the radio is using?

Since you already tried a Rx battery, I doubt that it is voltage droop, so this sounds like an interference issue.
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Old 03-23-2008, 06:42 AM   #3
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Quote:
Originally Posted by CarbonJoe View Post
Since it only happens at partial throttle, (not at initial throttle up when the current draw is greatest) it sure sounds like the speedo's switching frequency is causing interference with the radio. I would try moving the Rx antenna around, move the Rx away from the speedo, and try re-routing the servo wire, especially if the wires are all bundled (zip tied) together. Can you change the channel that the radio is using?

Since you already tried a Rx battery, I doubt that it is voltage droop, so this sounds like an interference issue.
Thanks for the reply. I tried unbundling the servo wires because I know the bundling creates an electromagnet wave around it, I also tried putting the receiver over the servo away from the ESC, and soldered 3 capacitors on the motor too, but nothing even made an effect. I am totally confused
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Old 03-23-2008, 07:34 AM   #4
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I had servo glitching probs last week. Took me lots of time to isolate the problem. It turned out to be an ESC wire that was partly shorting. That was the first time in years that an ESC caused a servo glitching problem.

If you have another ESC to try, swap yours, see if that helps.

Obviously swap each component until you isolate the problem.
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Old 03-23-2008, 08:07 AM   #5
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Do you have a different brand of ESC to try, even temporarily? How about a different Rx? Servo? Try switching the port on the Rx that the speedo and servo are plugged into (then the wheel will control the throttle, and the throttle the steering) to see if the interference follows the port on the Rx.

Did it just start doing this, or is it a new installation?
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Old 03-23-2008, 08:36 AM   #6
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hi bro, try change d motor......i ever encounter this problem before...i chg ESC, chg Receiver, change servo, but d problem still occur...after i chg motor, my problem solve...i suspect is d motor endbell.
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Old 03-23-2008, 11:03 AM   #7
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Mine did the same thing. I later found the soldier joint on the Checkpiont Money motor had broke during one of my accidents. It is the joint between the brush tab and the capacitor. It worked great at lower speeds until I started the race. Once racing it wanted to turn into the wall during breaking. I reconnected the soldier bridge and it has been working great ever since. Hope this helps.
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Old 03-23-2008, 12:26 PM   #8
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Hi guys,

thank you all for your input. Unfortunately I can't replace anything bcz I don't have any spare parts. Yet, I discovered another thing, I connect the receiver battery to the receiver, turned-off the ESC and removed the main battery pack so now the servo is running on the receiver's battery. I got a screwdriver and started touching it on the motor- mind you again no power to the motor, every time I did that the servo glitched.

Does that give you any clue?
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Old 03-23-2008, 12:46 PM   #9
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1. make sure the antenna wire doesn't touch carbon fibre or metal, or being too close to motor / esc.

2. make sure plug to plug connection from esc to rx is still tight fit. A wear out plug connector means the electric current needed for servo is less & noisy, possibly causing it to glitch. Most people have this problem : poor esc to rx connection. Solution: Installed a new plug connector.

3. The crystal in rx is half damage. Buy a new crystal from Sanwa to test. Most people have this problem too : a damage rx crystal.

4. The capacitors installed on the motor are damaged. Replace them and try again.

5. IF ALL THE ABOVE FAIL, YOUR ESC IS BROKEN.
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Old 03-23-2008, 01:49 PM   #10
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I FOUND THE PROBLEM!

I changed the motor circuit and brushes and now not a single glitch!

Thanks for all the inputs and suggestions everyone!
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