Antenna Locations

[huntaero]

I was looking at these antennas for the comm, Transponder and ELT, from Advanced aircraft they say they don't need a ground plane has any one had any experience with these antenna's

http://www.advancedaircraft.com/

[Chris In Milwaukee]

They're a center-fed dipole, so you're right, they don't require a ground plane. I think we've discussed this in the past, or similar homemade ones. I can't remember if folks were seeing interference with the steel structure or not, or the silver layer in the fabric paint. Certainly a good solution for a composite or wooden aircraft.

[whee]

https://bearhawkforums.com/forum/product-reviews/34602-advanced-aircraft-electronics-antenna

I was going to use one till I found out I could make the same thing myself for significantly less. Well find out pretty soon if mine work.

[rodsmith]

I was interested enough to call them several times, no one ever answered or returned my call.

[Bcone1381]

Me too. No joy via the phone. I just sent a request to respond to this thread via e-mail. I see they advertise in Sport Aviation every month, and sell their product through Aircraft Spruce.

[Bcone1381]

This is a dipole comm antenna I made for my S7 about 25 yrs ago. I plan to use it in my Patrol. It seemed to work really well and does not require a ground plane. It is easy to mount using adel clamps on the ground end to connect to fuse tubing. The whip end just goes through a grommet in the fabric. The whip is just cut from a stainless car antenna and the ground is an aluminium tube.

Can you tell us more? How was it fabricated, and where it was mounted? What was its useful range?

[jim.mclaughlin924]

It was mounted behind the baggage compartment with the antenna half through the fuse top, slightly swept back, and the ground end clamped to the fuse tubing inside. I put a small reinforcing patch on the fabric with a grommet for the antenna to go through. The range was never a problem, I would guess about the same as my Bonanza.
It was simple to make and costs next to nothing. I remember that drilling a small hole in the end of the stainless rod to solder the coax center into was the hardest part. Still took and hour or two start to finish. If you want to try it, I can probably make a sketch.

[Ivan]

I want to build this, a sketch would be helpful.

[patrickh99]

Similar antennae, with advice on how close to mount to metal structure: http://www.rstengineering.com/rst/pr...20Manual-s.pdf

[svyolo]

I printed that link to a pdf. It was awesome.

[Archer39J]

Neither manufacture's page indicate these are suitable for use inside our metal fuselages. I don't mean to be a pessimist, but it really seems like mounting a 6-10 watt VHF transmitter inside a steel cage is not the way to go.

[svyolo]

I have built less than 2 dozen antennas, a few on cars, mostly, on fiberglass boats, and mostly HF. This thread was very educational, on a subject that really didn't catch my attention all that much. I never even thought of building an antenna inside, or around, a steel cage.

Thanks for the responses.

I am guessing I will buy my antennas, and install them on the outside.

[whee]

Neither manufacture's page indicate these are suitable for use inside our metal fuselages. I don't mean to be a pessimist, but it really seems like mounting a 6-10 watt VHF transmitter inside a steel cage is not the way to go.

Not a pessimist but realistic and following best practices. I pretty thoroughly studied the RST Antenna Manual and other technical sources and knowingly went against some best practices. Radios have always been a sort of black magic to me and I'm looking at this as a learning opportunity.

There is some anecdotal evidence that an internal dipole antenna will work inside a tube and fabric airplane. The Stearman clubs reported they work, a guy with a cub placed an AAE antenna along a belly stringer and reported it worked, another guy with a cub put one in his vertical stabilizer and reported it worked.

Whether an antenna 'works' is probably somewhat subjective. If I get 30mi range with my antenna then I'll be satisfied and say it works; I'm sure Jim Wier would disagree.

[Bcone1381]

http://www.aeroelectric.com/Referenc...rcher/Tip7.pdf

This is a Bob Archer antenna tip for tube/fabric aircraft I found thru Bob Nuckolls' Aeroelectic Connection. Go to P.2 for the Quick Start up guide. I have no antenna experience, so this is just book knowledge from a respected source.

I wish I knew when it was written. The recommendation of the GPS antenna location of "inside the top fabric, no ground plane required" simplifies and cleans up the GPS antenna installation. I am seeing aircraft with multiple external GPS antennas having that impact appearance and did not know they could be mounted inside the fabric.

[Archer39J]

http://www.aeroelectric.com/Referenc...rcher/Tip7.pdf

This is a Bob Archer antenna tip for tube/fabric aircraft I found thru Bob Nuckolls' Aeroelectic Connection. Go to P.2 for the Quick Start up guide. I have no antenna experience, so this is just book knowledge from a respected source.

I wish I knew when it was written. The recommendation of the GPS antenna location of "inside the top fabric, no ground plane required" simplifies and cleans up the GPS antenna installation. I am seeing aircraft with multiple external GPS antennas having that impact appearance and did not know they could be mounted inside the fabric.

Thanks for posting that, I found that early in my research but it's been a while and I forgot it was out there. There are Bob Archer comm wingtip antennas also, but with such a limited vertical space from what I've read the range wouldn't meet my expectations.

I thought about recessing my GPS antenna on a tray between the dorsal stringers, but the GNS430W manual started talking about horizon shadowing on the order of 5 deg so I figured I'd go ahead and mount for optimum performance. It'll be my only external GPS, my backup can live on the dash.

[Bcone1381]

Whee, How is that Advanced Aircraft Electronics internal dipole Com antenna working out for you?

[whee]

Whee, How is that Advanced Aircraft Electronics internal dipole Com antenna working out for you?

I didn’t end up using the AAE antenna. We made our own which seemed to work fine;never got any complaints. But we had a radio issue we thought was the antenna so we changed it. It didn’t end up being the issue but since we already had the new antenna installed and I’m sure it is better we left it hooked up. The old antenna is still installed Incase we ever have a use for it.





New antenna is a Delta Pop mounted to the tunnel.

[Helidesigner]

I installed a bent whip antenna on the stainless tunnel pan behind the fire wall. No problems. I just need to wipe it with a rag once in a while. It is very easy to run the antenna cable to it there.

[zkelley2]

Has anyone thought of mounting the comm antenna to the metal between the wings and fuselage? Or is that too small or big?

I have fibeglass wingtips and have thought about putting antennas there, but worry about shadowing out there and that they are reported to not work on RVs well and I think we'd have the same problem.