The 2.4 Wind Direction Aerial.

Since 2.4 radios started showing up things have changed in the way we fly. With the short antenna it is harder to fly with out the ribbon at the top. So we came up with a solution. With the hard mount the rod is removable for transport. Standing 18" tall it gives just enough height for the ribbon. This makes for a great addition for the DLG pilots.

Merrill


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Originally Posted by Mr B....

The 2.4 Wind Direction Aerial.

Since 2.4 radios started showing up things have changed in the way we fly. With the short antenna it is harder to fly with out the ribbon at the top. So we came up with a solution. With the hard mount the rod is removable for transport. Standing 18" tall it gives just enough height for the ribbon. This makes for a great addition for the DLG pilots.

Merrill

Merrill,

Man off us already have done this. Adam Weston had a setup at the last two IHLGFs and David Klein had a thread dealing with mods to TX's utilizing a JR antenna that retracts.

I also made one by wrapping my JR antenna with plastic, then wrapping that with epoxy and CF/FG I mounted it flat on a piece of plywood with Blind-nuts, added a screw to hold the TAantenna in like a anormal TX, then filling everything. I added a mount that was sanded to fit the TX surface. I then drilled 3 holes for screws whihc screwed in frominside the TX. This gave me a mount that I did nothave to remove.

then Bruce Davidison sent me some 1/4" rip stop material in long lengths, that was very light and flapped inthe wind easily.

I tended to try not to block the button for binding my TX with the RX.

Each does it a fferent way.

Chris

Mine...

nice work, Merrill. i am glad it came to fruition. i like it! the 2.4 community needed this.
cheers
paul

Guys,

Using a carbon or metal pole right next to the 2.4 antenna is going to seriously mess with the output radiation pattern. And if you are unlucky it will reduce the effective output. It can also potentially couple back through the transmit antenna a signal that is out of phase and result in heating the finals. Please use something non-conductive.

Gerald

Originally Posted by G_T

Guys,

Using a carbon or metal pole right next to the 2.4 antenna is going to seriously mess with the output radiation pattern. And if you are unlucky it will reduce the effective output. It can also potentially couple back through the transmit antenna a signal that is out of phase and result in heating the finals. Please use something non-conductive.

Gerald

Are you saying I should also not stand next to my friend whose Tx is on 72 mHz? Hmmm?

Originally Posted by G_T

Guys,

Using a carbon or metal pole right next to the 2.4 antenna is going to seriously mess with the output radiation pattern. And if you are unlucky it will reduce the effective output. It can also potentially couple back through the transmit antenna a signal that is out of phase and result in heating the finals. Please use something non-conductive.

Gerald

The first generation Futaba 10C is 72 or 2.4. Just change the transmitter module. I use the 2.4 module and partly extend the retractable antenna for my streamer. I range out to my visibility limit. No issues.

Jun C.

What about putting mylar on the end of your 2.4ghz antenna?

I have a 2.4 ghz setup and have been weary of doing the mylar streamer on it so I made a ~10 inch piece of ripstop nylon. Could I use mylar streamer?

Ryan

Thermaln2,

Yes, you shouldn't. But that is a different issue. It used to be well known in the past but seems to have been forgotten that one transmitter next to another will intermodulate it somewhat. It probably affected things more in the AM era where it was more obvious. At least most of our transmitters are not shielded at all. If a signal couples into the input of the amplifier chain in the transmitter that signal will get amplified as well. This causes distortion. It can also cause your or the other guy's transmitter to splatter RF at frequencies it shouldn't be sending on. That could hurt everyone's reception by a small bit.

The two antennas a couple of inches apart issue is substantially that they are in each other's near field. RF will couple between them. They will inductively and capacitatively couple. This proximity changes the output impedence of the "real" transmit antenna which could cause some issues for the circuitry perhaps reducing output power and increasing heating, as well as definitely distorting the output radiation pattern. It may improve it in some directions but likely hurts it worse in others. Unless you have mapped it out you have no idea.

Please study up on the issues some. I have, having done some research into antennas before and as a HAM operator.

Gerald
KE4ET

Originally Posted by G_T

Using a carbon or metal pole right next to the 2.4 antenna is going to seriously mess with the output radiation pattern. And if you are unlucky it will reduce the effective output. It can also potentially couple back through the transmit antenna a signal that is out of phase and result in heating the finals. Please use something non-conductive.

Although in principle I guess this could happen, I'd be very surprised if a conductor of those dimensions did anything at all to the emitted distribution in the far field. I wouldn't worry about coupling back into the tx either: it'll be the square of an already tiny fraction of the emitted power.

That said, there's no substitute for range checking

New product from M M Glider Tech!

We are announcing that we are now manufacturing a 2.4 Wind Direction Aerial. It is manufactured with a Urethane base mount that can be bonded to the back side of the TX with RTV or double sided tape. The aerial is a 3/16" X 18" long White fiber glass rod that was made to be removable from the base for transporting. It can also be ordered in a longer length. Attached to the one end of the aerial is a mounted mylar ribbon. For more details look on the www.mmglidertech.com web page on the accessories page. The part numbers are MM-108 & MM-109.

We are happy to support this great hobby!

Safe Flying!

Mr B.

thats more like it, Merrill! you just needed a little bit of marketing panache
cheers
paul

Originally Posted by Mr B....

New product from M M Glider Tech!

It is manufactured with a Urethane base mount that can be bonded to the back side of the TX with RTV or double sided tape.

The aerial is a 3/16" X 18" long White fiber glass rod

Attached to the one end of the aerial is a mounted mylar ribbon.
Mr B.

Well that should be good for no radio RF interference and the mounting looks great and with the rod being removable I can still get My radio back in My radio case.

Looks Great Merrill a good solution to the short antenna.

Clarence

Merrill,

I think it is a great idea and a much needed product for many of us.

I'd recommend getting one!

Chris

I fly a JR 12X MV that I run on 2.4 but it also has the antenna for 72mhz. Two weeks ago I flew my Xplorer on 2.4 while using the metal 72mhz antenna pulled out about 2 feet with a tell tail and had no issues flying it at normal TD distances. I asked Larry Jolly if he thought it would be an issue and he said that he didn't think so.

On my X9303 I am using Merril's 2.4 Wind Direction Aerial and I really like it. Very high quality, the base is out of the way of my fingers, I can still get to the bind button just fine. Nice job Merril!

Clay