i have been flying a extra 300 for some time with the receiver antennae routed through an internal tube. i have seen this technique used on several build threads but one of our club pros noticed my setup and was adamant that this is a bad idea. any opinions out there? thx

....it sounds like your "club pro" needs to take a short course on how radio waves travel.
Radio waves are uneffected by structures such as your house. If they were not, you
wouldn't be able to hear a radio indoors. Your antennae inside your plane will pick up
the radio signals just fine....especially FM signals that travel differently than AM signals.

FBD.

Beats me why it would bother him. I have been doing it that way for as long as I can remember and I'm an old coot (:-).

I'm assuming here that you mean a small plastic tube and that it is separated from the other wiring as much as possible. I usually mount the tube along the top inside edge of the fuselage and exit the tail. However on my Senior Telemaster I surfaced just behind the trailing edge and attached it to the fin. I won't do it again though because I seem to catch it on too many things while in the vehicle or pit area.

I've been doing that for over 30 years. I guess I must be doing it wrong too, according to your club "pro".

Be kind to the "club pro", but do ignore his advice.

I use that technique whenever I can. Sometimes, a particular situation won't accommodate it. The last one I had that didn't like it was a H9 Twist 40 (3 years ago). It glitched intermittently, so I ran the antenna outside the fuse, and it was happy. Usually, when the fuse has enough space to hold the antenna, it's not a problem to have it inside. Range testing will let you know.

Actually,, it has occurred to me that the "pro" may be referring to something other than routing the antenna thru the tube and fuselage however it certainly seems that it's the tube that bothers him.

All radio waves travel the same whether AM, FM, PCM or ????. If your fuselage were made of carbon, was covered in metal or some other material that blocks RF, you would have a problem with the antenna inside the fuselage. However, most models consist of wood, non conductive covering, nonmetalic paint etc. so are not a problem or an obstruction to radio waves. You will be fine in all but the most specific case by putting your antenna inside the fuselage. The one place you could get into trouble is if you have metal push rods or pull-pull lines running parallel and close to the antenna.

I do the same thing, run the antenna through a tube inside the plane. But a couple of months ago, I was testing a Giant Goldberg Tiger for a friend, and I kept getting hit on short final. So I changed my pattern up, made it real tight and tried to avoid the geographic location where the previous hits had occured. It landed fine. Then it occured to us that the tube was straight as a string, going through the fuselage and might have been completely blanked out by the engine when the plane was coming straight at us. We rerouted the antenna and the problem didn't occur again. So, maybe there is something to it, especially if the engine is a big one. I don't know, I'm just saying...

that is the issue. he believes the antennae wire is too close to my cable pull pull rudder control. it flew fine for many flights until he noticed the situation. also, this is a 1/4 scale extra 300 with a large fuse, so i thought there was plenty of room.

Don't sweat it.

Everyone has their pet peeve. Some guys will harp on how important it is to care for your batteries, others will insist on wasting hours balancing props. These are not bad things by any means, but they are not as critical as some people would have you believe.

A good example of this is what happened to me this summer. I had an old Ultra Sport at my dad's house that I hadn't flown in years. One day while I was visiting him, I threw a battery and receiver in it just to make sure the servos still worked.

A few days later, he asked if I wanted to go flying. I didn't have anything ready, but he told me that he had charged up the Ultra Sport. So I told him to bring it out to the field and I'd meet him there.

He brought the plane out fully assembled in his van. I fueled it up and took off. Twice during the flight I got a pretty bad glitch at the approach end of the runway. Other than that, it was flying great, but those glitches told me that something was wrong, so I decided to land.

Again, on the approach, I got another bad glitch, but I landed safely.

I had my wife's car that day, so I had to remove the wing to get the plane back home.

When I took the wing off, I saw the cause of the glitches - The reciever was sitting tightly in it's cradle with the antenna still wrapped tightly around it!

There is an EXTREME case of "Antenna Abuse" whose only consequence was a few glitches - So I don't think that a few pull-pull wires or a plastic tube is anything to worry about.

Beware of club "Pros and Experts"!

Ed S

FYI... I used to fly discus launch gliders... with fuses in the 12 inch range... and wouild wrap the antena around a soda straw.. being carfule not to overlap with a slit at the far end to stick the end of the antenna through that woulid hold it in place and keep from unraveling... it's common place in the dlg world... never had an issue. I don't recommend it for anything else though.. [sm=47_47.gif]
MIke

I take an old pushrod and stick it in the rudder or elevator exit hole. Run it up through the fuse and tape on the end of the antenna. Pull it through the fuse trying not to wrap it around anything and secure it to the tailwheel via a rubber band and a servo arm. I suppose poking another hole through the fuse so as to avoid the rods or wires would be nice. Point is, I don't even use an inner fuse tube! My Cap 232 has pull-pull cables on the rudder too! No problems here.

i don't see why it is a problem either but when you have the club pro solving another problem on your plane you are forced to take all advice.