Interference problems
 

Moved a perfect running motor and ignition from one plane to another, in the new plane all I get is interference. I added a Smart fly power expander sport to the plane today hoping it would help it didnt! I spent the rest of the day moving 1 piece at a time, and starting the motor to see if I could isolate the problem.

Here is what I have done so far.
Moved ignition module to the front of the firewall...........no change
Moved throttle servo 15 inches back from ignition ..........no change
Moved receiver battery back to 12 inches from ignition........no change
Moved Smart fly back next to receiver........ no change
Moved Ignition cutoff LED up beside ignition power switch........ no change
Receiver is new for this plane, tried a second new receiver.......... no change

I need help from the rc world

Thanks

RE: Interference problems
 

Ihad to use a Sullivan Nyrod with a plastic clevice connected to the throttle level on the engine. Then my engine noise went away. Also is the spark plug wire shielded?

RE: Interference problems
 

What kind of radio and what frequency? What kind of receiver? I am assuming 72mhz here, is the crystal the same manufacture as the receiver? Have you tried another known proven good receiver from another plane? (if available)

Now on to the engine. It might help if you could post what brand/size etc it is. Is it possible that the plug lead was damaged in the move? Assuming metal shield plug cap, is it possible that the spring steel ring is missing from the end where it snaps onto the plug causing a poor electrical connection at the plug base?

RE: Interference problems
 

I am using 2.4- 7 channel fast receiver.
Engine is SPE 43 cc , double checked plug looks good, and the steel spring is still in place on the plug cap. Rubber boot is good with no breaks in wire.
I am using the Sullivan Nyrod with a plastic clevis.
I also as a last result took the receiver from the plane the motor originally came out of and put it into the new plane.. results where the same..

RE: Interference problems
 

Put a hose clamp on your spark plug cap. Tighten it onto the hex of the plug until it can't be easily moved around.

RE: Interference problems
 

jedijody

I will try this as soon as the sun comes up, the plug snaps on solid but it is easy to moved around..

RE: Interference problems
 

Master Jedijody

I have learned much under your teaching, as they say the master knows all..

Problem solved with your suggestion, off to the field for the maiden.

Thanks again..

RE: Interference problems
 

:D.

RE: Interference problems
 

Success Success.. Flew great.

RE: Interference problems
 

Good for you, as absolutely nothing beats the feeling of a successful maiden flight with a new model.

Karol

RE: Interference problems
 

I'm curious. I thought a 2.4GHz receiver was supposed to cure ignition related noise. You mentioned that it is a fast receiver. Do you mean Futaba FASST or some other brand? Sure glad you had a successful flight.

RE: Interference problems
 

While 2.4GHz radio systems are less prone to accept some forms of RFI they are far from immune.

RE: Interference problems
 

I am using the Futuba Fast system.

RE: Interference problems
 

I have a 2.4 Spektrum the needed the batteries seperated and the ignition module shielded to get rid of the glitches. They can be hit. Just takes a little more interference to do it. I cut out a tin can and fitted it around the module. Then grounded that to the engine

RE: Interference problems
 

I think I would send that module back and get another one.

RE: Interference problems
 

Something a lot of people miss when thinking of interference is the problems doesn't have to enter through the receiver antenna. The "noise" can enter anywhere in the circuit. If you take your transmitter and hold it very close to a servo on your plane the servo will usually start jittering. The radio waves from the transmitter are being picked up by the controller board inside the servo. RFI from the ignition can enter and disrupt the radio system in much the same way. It could be entering at the servo controller boards so in this case it wouldn't matter what kind of radio system is being used, 2.4ghz or otherwise. The "noise" is entering the system after the receiver.

RE: Interference problems