[Luke Planemaker]

Thinking of making an aluminum tube fuselage, and covering with fabric. Will this be possible with FM/PCM radio, or will this cause radio interference. Can I just run the antenna out the top, to the tail? Probably put aluminum tube in wing also. Has anyone got experience with a similar structure setup? Need some advise on this.

[kip51035]

On real A/C they run a shielded antenna cable from the radio to a special fitting or an antenna mounted on the skin and the antenna length or configuration is figured from the skin out. Yes you can expect the aluminum fuse. to inhibit the reception. The skin is used as a ground plane and enhances the reception.
Kip

[Wayne V]

I always wondered if that would be a problem, it reminds me of a test they did on Daily Planet on the difference of AM and FM signals, the host had a small AM/FM radio, tuned in a radio station on AM, placed a metal soup can over the small radio and then there was no sound coming from the radio, so on AM the signal was totally lost from the shielding of the metal can, funny thing was on FM the radio just kept playing with no loss of signal.
It would be an interesting test to do the same at 50 feet with a RX ( and antenna wire )under the can and a servo sticking out of the can and see if the servo still works with the RX under the can.

[Luke Planemaker]

Hi Kip, and thanks for the reply. I'm thinking aluminum frame, with fabric covering, not aluminum skinned fuse. Not sure what you mean by "skin is used as a ground plane" though. Would it help to have the receiver right up to the fabric so the antenna is better exposed? Does the signal get messed up, when a long piece of metal comes between antenna and radio signal? I'd like to have a 4 tube fuse frame, with maybe a couple tubes in the wing. Must be some RC planes built similar to this?

[Guest]

Model helicopters have been using aluminum frames since AM radios were all we had. Should work fine as long as you follow common sence: no loose metal to metal contact, everything tight, and keep the antenna out in the open.
Joe

[Luke Planemaker]

Thanks for the info Joe, never even thought of heli's with aluminum booms. Are the antennas streached out under the boom on them? Where is the receiver usually located on a heli? Feeling better about this idea now.

[Guest]

(72Mhz)Reciever is usually in the front with antenna going down to a landing gear, strait back to the end of the gear, then continuing back and up to the boom; best to avoid the antenna from being parallel to large metal parts.

(2.4G) Two or four little antenna positioned as manufacturer recommendations to give best line-of-sight from all angles.

Joe

[Luke Planemaker]

Wayne, not sure how I missed your post, but I see we posted at the same minute. The soup can info is good to hear, I'll have to rig up some kind of test cage, for sure.

Thanks Joe. What kind of range would you dare fly a heli at? Or are they OK as long as you can see what it's doing, and distance isn't really a factor? Not really sure what FM/PCM is capable of, distance wise. I imagine signal gets weaker closer to ground?

[hellyeh]

Luke , here's a site that may give you some inspiration , as well as answers .

http://www.allmetalplane.com/

[Luke Planemaker]

Thanks for the link, I made that sound Beavis and Butthead make, when I saw the Zenith 801. Too bad His building tech page is still under construction. Looks like his antennas just come out behind the wing, and go to the tail.