CB36

Hi all,
This was a first for me. I resurrected a Futaba 72 I haven't used in a couple of years. The batteries checked out good on my cycler. I did a range check and all seemed OK, but after takeoff, when the plane was out a bit, there was a pronounced "dip". There was no wind and nobody else on the freq, (club field). I landed and enlisted a buddy to listen closely to the servos, (engine off), collapsed the antenna and started walking. Sure enough, maybe 100' out the aile servos started to buzz. Further walking produced aile jitters and a couple of deflections. That would explain my "dip" during flight.

Where do I start to ferret out the gremlin?

Thanks!

ggraham500

My Feedback: (4)

Check/replace Y harnesses.

You didn't say what type engine ... electric, glow/nitro, gas. Gas is pretty noisy and lots of vibrations.
Do not use metal to metal contacts when connecting throttle, etc to a gas engine.

My 2 cents.

CB36

It's in a Hangar 9 80" Cub. Motor is an OS FS70. No Y-harness. Rt and Lt ailerons are on separate channels, (I wanted to adjust the travels separately to get differential).

dirtybird

My Feedback: (5)

Aileron servos would not cause it to dip. They would cause it to roll. Check your elevator servo.

Rodney

If your batteries are still holding up, I'd suspect a bad or intermittent connection somewhere. Do you have any extensions? If so, mate/demate/mate a few times to scrub off any possible corrosion in the connectors. Also check the connections where they plug into the receiver to be sure there is no corrosion there. Also, make sure that your transmitter antenna is firmly screwed into the transmitter connection. some of those older units can unscrew themselves as you repeatedly extend/retract them.

CK1

My Feedback: (60)

After checking all leads , servos ,switches and antennas. Did you perform your range test at a different location and get the same results? Check for any signal interference on or near your channel at your field . Any transmission towers near your field?

1THEPALMER

My Feedback: (1)

Also remove and clean the antenna.
I just retired a 8UAF as the internal wires from the sticks were breaking right @ the end of the strain relief point. They are glued into a slot and after a lot if trouble shooting found the indivudal strands were broken inside the insulation (work hardening?) The radio has outlived four battery packs. Your has sat so look to the antenna first.

jmdairplane

if your flying someone else could be flying any where with in three miles away you could get jitters or interference thats a possibility.