Interference
 

I am new to gas and need some advice on set up. First of all I am flying a DP Extra with a Fox 2.4. Range test with the engine off is good. Range test with the engine running and antenna down is very poor (10 feet). Range test with the engine running and antenna extended is good. Here is my set up .... the receiver antenna is running down the inside of the fuse in a plastic tube and exits just above the right elevator servo. Is this a problem? My throttle linkage is nyrod but my throttle servo is mounted on the right side of the fuse just one inch above the receiver. Is this problem? The only other metal in the plane would be the pull-pull set on the rudder but that seems to be normal on many planes. My switches are separated by 8 to 10 inches. My ignition battery is on the fire wall and the plane battery is inside the fuse ... separated by 10 - 12 inches. Any suggestions would be appreciated.

Mark

Interference
 

Try re-routing the antennae to see if you can improve the range.

Interference
 

Try, first as mentioned above. Then check for anything loose, like muffler,??, I don't know how Fox grounds their engines but make sure it is secure if it is a separate ground wire.

Interference
 

Check your spark plug caps. if they are not tight or have a bad cap that will do it. alot of people put hose clamp on them so they don,t move. Poor grouding. Anything that is viberating cause sound.

Some suggestions
 

10 feet! - wow that's really really poor. There is something going on here.

First change out the receiver and better - use a PCM receiver on gas engines. (They are somewhat less susceptible to interference.) Second, check for anything loose that could be metal on metal. Third, reroute the antenna outside the fuselage (at least temporarily) well away from servos and their wires. (I have had poor luck with internal antennas close to servos, particularly digital servos) Check for engine grounding as suggested. Check range again.

Let us know what happens.

Gerry Rosebery
Melbourne, FL

update
 

Did as you all suggested and then some ... no change. I even thought it might be a bad servo some where so we disconnected each channel one by one. Still nothing. We did discover that when the antenna wire is held streight verticle out of the center of the fuse everything cleared up. Additional thoughts? Could it be the ignition box is bad?

Re: update
 

You must have a problem with your ignition system. What spark plug does the Fox use? Can you get a resistor plug for it? (It will have an R in the number) If you can't get a resistor spark plug the shielding for your spark plug lead must have a break and is leaking RF. I would send it back to Fox for replacement.

Re: Re: update
 

Fox uses Champion. I put a Bosch in it yesterday as part of the attempt to fix. I sent Fox an email ... I think you are correct, it needs to be sent back. Thanks!