Servo Spasms

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Ed Kettler
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Joined: Sat Dec 15, 2001 6:05 pm
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Servo Spasms

Post by Ed Kettler »

I am running 72mhz/ch 44, and encountered a rather odd problem. All of my combat planes run ailerons off a Y harness, and one setup appears to be "allergic" to this configuration. I am using GWS Mighty Micro BB for aileron servos, and when I plug in the Y harness, all servos go into uncommanded spasms. Unplug one of the aileron servos, everything is fine. Ahah, I've isolated the bad servo! NOT! Swap plugs, either servo works fine individually, but plug in the second and the servos dance (including throttle and elevator). Swapped the Y harness, same problem with both plugged in.

I swapped another wing to test to see if it was the receiver, and it worked fine. It is something about the servos.

For a work around I am using channels 1 and 6 without the Y. Any ideas on the cause and solution would be greatly appreciated.
Vapor
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Joined: Mon Mar 26, 2001 8:43 pm

Post by Vapor »

You have a bad voltage drop somewhere,check battery under load, check your y-harness under load, ect.
Web-Pilot
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Post by Web-Pilot »

Hi Ed,

I have seen this problem before, although it was not on a combat plane. There is too much voltage drop on the Y harness. The only way I could solve the problem was on of two ways, eliminate the Y harness and use a separate channels for each aileron, or use a heavy duty Y harness with larger wire size. I had to go to a Y harness with 22 gauge wire I believe to solve my problem. It also goes without saying to keep the leads as short as possible.

I also found one receiver that was much more sensitive to Y harness use than any of the others. That one happened to be an XPS 2.4 Ghz rx though.

Hope that helps.
George
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