unusual motor inteference
09-11-2011, 07:50 PM
#1
Thread Starter
unusual motor inteference
I have just completed a hellcat with a ralph cunningham ignition converted G-62. The radio is a JR 12X with 1221 receiver on 2.4. Before running the engine to do test flights the radio was rock solid on the ground. When you start the motor (which runs awesome on ignition) the ailerons roam. Not fast jittery but are moving on their own and the servo clearly is driving it (both servos on same channel thru a Y connector) which you can feel when you grab the aileron. You can kinda override with the stick in the sense that the ailerons will move in response to stick movement but roam even with that. Taxi testing reveals full authority on all channels except the ailerons which continue to roam. Obviously no flight testing attempted. When motor is shut off, full authority on the aileron with no movement except in reponse to the stick. Switched out the receiver to identical receiver that I have been flying in another plane and same phenomen occurs. The ignition is typical cunningham hidden away where the starter spring normally would be. The receiver battery is probably 8 or 10 inches away from that but all other radio gear way back in fuse with no metal to metal contacts. I am quite perplexed and open to suggestions or thoughts.
09-11-2011, 08:38 PM
#2
Senior Member
RE: unusual motor inteference
ORIGINAL: roydefiant I have just completed a hellcat with a ralph cunningham ignition converted G-62. The radio is a JR 12X with 1221 receiver on 2.4. Before running the engine to do test flights the radio was rock solid on the ground. When you start the motor (which runs awesome on ignition) the ailerons roam. Not fast jittery but are moving on their own and the servo clearly is driving it (both servos on same channel thru a Y connector) which you can feel when you grab the aileron. You can kinda override with the stick in the sense that the ailerons will move in response to stick movement but roam even with that. Taxi testing reveals full authority on all channels except the ailerons which continue to roam. Obviously no flight testing attempted. When motor is shut off, full authority on the aileron with no movement except in reponse to the stick. Switched out the receiver to identical receiver that I have been flying in another plane and same phenomen occurs. The ignition is typical cunningham hidden away where the starter spring normally would be. The receiver battery is probably 8 or 10 inches away from that but all other radio gear way back in fuse with no metal to metal contacts. I am quite perplexed and open to suggestions or thoughts.
(especially if used previously with other brand servos or RX)? If so,please refer to
After Market Accessories - Ignition Systems, Leads, Modules & Switches - Cautions.
See also sub Section "Glitches & Jitter in Receiver, Servo & ESC - causes and cures " under
"Radio Systems, Accessories, Alterations and FAQ." at:
Alan's Hobby, Model & RC FAQ Web Links
Alan T.
09-12-2011, 04:59 AM
#3
My Feedback: (2)
RE: unusual motor inteference
ORIGINAL: roydefiant
I have just completed a hellcat with a ralph cunningham ignition converted G-62. The radio is a JR 12X with 1221 receiver on 2.4. Before running the engine to do test flights the radio was rock solid on the ground. When you start the motor (which runs awesome on ignition) the ailerons roam. Not fast jittery but are moving on their own and the servo clearly is driving it (both servos on same channel thru a Y connector) which you can feel when you grab the aileron. You can kinda override with the stick in the sense that the ailerons will move in response to stick movement but roam even with that. Taxi testing reveals full authority on all channels except the ailerons which continue to roam. Obviously no flight testing attempted. When motor is shut off, full authority on the aileron with no movement except in reponse to the stick. Switched out the receiver to identical receiver that I have been flying in another plane and same phenomen occurs. The ignition is typical cunningham hidden away where the starter spring normally would be. The receiver battery is probably 8 or 10 inches away from that but all other radio gear way back in fuse with no metal to metal contacts. I am quite perplexed and open to suggestions or thoughts.
I have just completed a hellcat with a ralph cunningham ignition converted G-62. The radio is a JR 12X with 1221 receiver on 2.4. Before running the engine to do test flights the radio was rock solid on the ground. When you start the motor (which runs awesome on ignition) the ailerons roam. Not fast jittery but are moving on their own and the servo clearly is driving it (both servos on same channel thru a Y connector) which you can feel when you grab the aileron. You can kinda override with the stick in the sense that the ailerons will move in response to stick movement but roam even with that. Taxi testing reveals full authority on all channels except the ailerons which continue to roam. Obviously no flight testing attempted. When motor is shut off, full authority on the aileron with no movement except in reponse to the stick. Switched out the receiver to identical receiver that I have been flying in another plane and same phenomen occurs. The ignition is typical cunningham hidden away where the starter spring normally would be. The receiver battery is probably 8 or 10 inches away from that but all other radio gear way back in fuse with no metal to metal contacts. I am quite perplexed and open to suggestions or thoughts.
09-12-2011, 05:53 AM
#4
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Location: Lyndonville, VT
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RE: unusual motor inteference
+1!
If you do need to have a "Y" harness, particularly if you're short on locations to plug in a battery on a receiver, then these little circuit boards from Hansen Hobbies make for a very reliable "Y" connection.
http://www.youtube.com/watch?v=KOI686bRLTI
Pete
If you do need to have a "Y" harness, particularly if you're short on locations to plug in a battery on a receiver, then these little circuit boards from Hansen Hobbies make for a very reliable "Y" connection.
http://www.youtube.com/watch?v=KOI686bRLTI
Pete
09-16-2011, 03:24 PM
#6
Thread Starter
RE: unusual motor inteference
Problem fixed. Replaced Y connector with a short one (only 2 inches to bifurcation, previous was about 12 inches to bifurcation). Also used 2 JR RF interference ferrite rings, one each at the receiver end of the extensions plugged into the y connector and ailerons. Now rock solid with motor running. Now ready for test flights.
