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Leadchucker
08-10-2008, 07:30 AM
Well,I learned something about electrical noise today,I think.. Just went through the glitches thing with a Modeltech Fledgling. Ground test showed all was fine on run up,then hit the throttle and headed her down the runway. Hit the throttle about 3/4 power for departure straight out after take off and over on her back she went. Backed off on the power and somehow managed to get her back after a rather spectacular series of unknown(and uncontrolled) aerobatic maneuvers.

Came about on downwind leg,made left base leg and went on final with a blip of power and put her on the runway. Popped wing and hatches off, checked all plugs and connections agian,did a runup and all is good. Down the runway and 1/2 throttle and all is well. Up to a safe altitude to do some stalls and right/left turn to see how she handles. Seem all right now, hit the throttle a bit to check out the higher speed handling and,a series of quick and voilent righthand rolls and loops ensued. Back down the throttle again and put her on terra firma rechecked everything again,redid range check and checked everything I could think of. OK, one more time. Off we go and this was a fatal mistake as she screwed herself into the ground about 100 feet off the end of the runway and destroyed the fuselage.

Radio is a Hi-tech laser 4 with the 8 channel Supreme receiver,HS-322 servos which seemed like a good unit. The motor and ESC/BEC is some generic offshore brand which I now think is the culprit in the electrical noise. New fuselage is on the build bench,but I think I'm dumping the motor/ESC items for a Axi/Jeti combo as I have never had any problems with them as far as radio glitching. All wires will be shielded,twisted and so on just as a safety precaution. Might go a bit smaller on the motor as I think this plane don't need that kind of power and the stock motor eats up a Thunderpower 3 cell/2100maH LiPo in no time. Any suggestion for power or any comments in general to sort thing plane out. By the way,it flys just fine at 1/4 power, scoots aloong nicely and handles cleanly and crisp with no other bad habits. She will fly again!

(Sorry for the long post:o)

Rabbitcreekok
08-11-2008, 04:40 AM
Consider investing in a Spektrum DX7 or other 2.4 Ghz radio equipment. No glitching or shootdowns.

CHELLIE
08-12-2008, 05:24 AM
Consider investing in a Spektrum DX7 or other 2.4 Ghz radio equipment. No glitching or shootdowns.

Or a Berg Receiver for FM, if 2.4 is too much money for you at this time, never never had a glitch, with a Berg Receiver, they are the best of the best, for FM, none better, and they dont cost that much, here is a link if your interested in getting a Berg Receiver, and getting rid of your glitches on FM, thats all that I use now, Hope that helps, Chellie

PS on the berg receiver crystals, use a little piece of tape to secure the crystal in place, its just cheap insurance.

http://b-p-p.com/product.php?productid=70&cat=18&page=1

gyrocptr
08-12-2008, 08:06 PM
Kit Name: Fledgling EP 4-Ch Trainer ARF
Manufacture: Modeltech
Construction: Balsa Built Up
Wingspan: 55.5 inches
Wing Area: 495 sq.in.
Flying Weight: 2.5-3.1 lbs
Airfoil: Flat Bottom
Motor: Speed 600 brushed
Battery used: 2s 2100mAH Li-Po Impulse
ESC used: Ripmax XTRA 35 A
Radio equipment: 4 Channel, 4 Std. Cirrus Servos CS601/BB

If you have the stock setup but changed from a 2S to a 3S Lipo, you may have exceeded the capacity and/or overheated the BEC. Many ESC-BECs cannot handle the current demanded by 4 full-size servos (HS-322) when the ESC is used with a 3S Lipo. The associated drop in BEC-voltage to the Rx can cause glitching.

Leadchucker
08-14-2008, 02:14 AM
Thanks for the suggestions. I think the 2.4 Ghz is the way to go.

If you have the stock setup but changed from a 2S to a 3S Lipo, you may have exceeded the capacity and/or overheated the BEC. Many ESC-BECs cannot handle the current demanded by 4 full-size servos (HS-322) when the ESC is used with a 3S Lipo. The associated drop in BEC-voltage to the Rx can cause glitching.

The Fledgling is a Gen II version with B/L motor and the matched supplied ESC w/BEC so me thinks it wasn't the ESC but rather electrical noise. I am only running 3 servos with the 4th channel on throttle via the ECS. Thanks for the tip though.