What is the best route for the antennae for a JR 7channel FM receiver, the chinese instructions don't say. The other question is where is the cheapest place to get the tail restraint that goes into the ground, or can one be made? I do have access to a welder but not sure how to make one.

Route the antenna straight back, as far away from other equipment as possible. I try to get the antenna out of the fuselage as quickly as possible. Don't kink, sharply bend, or double back the antenna. I usually drill a small hole in the bottom of the fuselage and route it against the fuse straight back on the belly. You can't see it that way, it's outside of the airplane right away, and it's nice and straight.

A tail restraint can be made out of PVC pipe, a few joint pieces, and foam padding. Every hobby shop I've seen has a padded metal restraint that's pretty cheap as well.

I run my antennae out the top of the fuse, typically just behind the canopy or wing's trailing edge, and run it to the top of the vertical stab, allowing the rest to hang back. See the photo. A pin is placed in the top of the stab, and a rubber band wrapped around that to hold the antanna taught without putting undue strain on it.

For the tail restraint, a popular way is to drive a tent peg or large screwdriver into the ground, tie a rope around that, and tie a large loop in the free end of the rope. Then the large loop is put around the hori and vert. stabs, and the plane is pulled forward until the slack is outta the rope. Be sure the slack is out of the rope before starting the engine.

Another popular way is to use a couple small diameter steel or aluminum poles (about 3' long, pieces of rebar or tent poles would work well) Drive them into the ground with a mallet, about 18" apart. The plane's wing is butted up against the poles with the fuse in between. Put the poles close enough together that one wing can't slip by if the other pole is against the fuse, but far enough apart that the plane is easy to get out of them.

J

I concur with Nathan King and that is the way I like to run all antennas especially in a trainer. Running them to the top of the tail is generally not needed and the trouble there is no matter how careful you are you will be subject to ripping out the antenna just from hanger rash. This is a senario I,ve have wittnessed time and time agine: Someone will stand arstride the fuselage holding the airplane back from the tail. This is fine except when you forget the antenna letting it go and kicking out the antenna. Pretty common.

I would like to add that the often recommended cutoff servo arm to slip a rubber band on or more forward (worse) to act as a strain releif is a really bad idea kinking the antenna even worse than what you are you are trying to prevent. Here is the best way to attach a small rubberband for tensioning and it will not harm you antenna like the other method will.


John

My 'tail restraint' is made of a dog leash and a dog tie-down (looks like a big cork screw with a handle on the top). I got them both at Family Dollar for $4 all together. I put one end of the leash through the leash handle, making a loop, and sticking the tail of the plane through the loop. Then obviously click the ring on the dog collar to the tie-down.

Some guys use the really long screwdrivers, and just pin the leash to the ground through the ring.

Good idea about using just a rubber band!

Although more work is involved in the control horn type strain relief, if done properly, there will not be any kinking of the antenna!

Choose a control horn long enough so that you can feed the antenna wire up into one hole then skip a few holes and pass the antenna back through several holes away. Chamfer all the edges of the holes you will be using with a #11 exacto knife.

Top or bottom, both work. I just happen to prefer routing through the bottom. I find that the antenna on top spoils the scale look, and it can be accidentally pulled a little easier.

Yup, that's true. I like warbirds (tho I own only one) and an antennae to the top of the fin is pretty typical on them. I pretend it's a scale detail.

'Course, those that see my 'stang know it's very un-scale anyway, but I like it up there!

Just so long as it stays outta the moving parts and away from metal bits, I'm happy

J

I have mine mounted on top in my Spitfire too. [8D]

Whatever you do, make the antenna installation straight, and DO NOT cut the antenna. It is not a cut-to-fit item.

"Whatever you do, make the antenna installation straight, and DO NOT cut the antenna. It is not a cut-to-fit item."

Innocently overlooked yet very important point!

Or just use 2.4GHz gear. Problem solved.

I just made one out of scrap copper pipe.

2 elbows, 2 caps, a T and some short pieces soldered together.
I covered the top part with foam pipe insulation wrapped with electrical tape.
Worked great today!

Pop

Here is how I've done a few planes, along the bottom of the fuselage. A rubber band to the tail wheel bracket keeps it straight and tight but doesn't pull too hard on it. I also use a discarded servo arm to make a strain relief where the wire exits the fuselage. this will protect the joint where the antenna is soldered to the receiver. I've also just held a few to the bottom of the plane with packing tape. It's kind of cheesy but works fine so long as the plane isn't something that looks really nice to begin with.

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From an electrical standpoint, the antenna does not need to be straight. It will work fine if not straight with no appreciable signal loss. You have to greatly reduce it's overall length to start to attennuate the reception. In spite of this wing (film) antennas are sold that have little effect on overall range, but provide for a great looking installtion.

Do not run the antenna back upon itself (if possible) or cross itself in a manner that is close to touching, however.


Another option, that I use in my tailless pusher planes, is to run the antenna out around the leading edge of the wing. Done correctly you can't even see it.

If the wing is not long enough for the entire length, I run the portion left at the tip, back then following the wings at the aileron lines.