Homemade dipole antennas for 2.4ghz

[Matts175]

Nice! I'll probably end up with amps some day. I can never leave anything alone.

 

[Matts175]

Hahaha. I just remembered I had this. I wonder what it would do? I wish I had 2.

 

[WilliamM]

Hahaha. I just remembered I had this. I wonder what it would do? I wish I had 2.

In a good tail wind, would make a great sail

 

[WilliamM]

Yup. I figured out what to use to stiffen it up. Just the cut off tail pieces from the zip ties that I used in place of anti drop pins on the camera, then just heat shrink over that.

I did this same thing, replaced the drop pins with zip ties. I was getting some shacking on the video, and felt it was the pins causing it.
On the dipoles I remember you asked me about turning one at a 90° to the other, also saw that mentioned in that tutorial on post #1.
Are you going to test one being 90° compared to both being vertical?

 

[Matts175]

I did this same thing, replaced the drop pins with zip ties. I was getting some shacking on the video, and felt it was the pins causing it.
On the dipoles I remember you asked me about turning one at a 90° to the other, also saw that mentioned in that tutorial on post #1.
Are you going to test one being 90° compared to both being vertical?

Yeah. I'll try it. It couldn't hurt. I'd go outside now.... but it's just been so crappy out. Bird came back soaking wet on the earlier run tonight. Makes me nervous when it gets wet. It was mighty foggy up by the lake. I have the day off tomorrow, hopefully it'll be nicer.

 

[yjander]

So what do you think about the set up I've got with one antenna facing forward and the other facing the rear? Any affect on performance that way?

Sent from my VS987 using PhantomPilots mobile app

 

[Matts175]

I would think it will be fine. The radiation pattern for a dipole (what we made) looks like this:

In other words... there really is no front and back to these antennas. They are what's referred to as omni directional. You could always take it for a flight and then just duct tape it to the other leg (so you don't drill a hole for nothing) and then try it out again. I only did mine like that because I saw Williams like that and I thought it looked cool. I'm not 100% sure which way they really go either.

 

[With The Birds]

I did this same thing, replaced the drop pins with zip ties. I was getting some shacking on the video, and felt it was the pins causing it.
On the dipoles I remember you asked me about turning one at a 90° to the other, also saw that mentioned in that tutorial on post #1.
Are you going to test one being 90° compared to both being vertical?

For a single antenna 90deg change in polarisation (ie vertical to horizontal) could introduce up to 20db reduction in signal strength. I suspect the dual antenna system on the controller is mimo so losses will not prove to be this significant.

 

[PhantomPhrank]

I see that the length of the T should be 58mm. Does it matter how long the stem is?

 

[N017RW]

I see that the length of the T should be 58mm. Does it matter how long the stem is?

Not in the real sense as it is not an active or radiating element. Of course there can be losses if it's excessive but not in the way it's intended to be used on this case.

 

[Matts175]

I see that the length of the T should be 58mm. Does it matter how long the stem is?

I read that it could be any length... so long as it's NOT 29mm (That's the length of each "leg"). The article was a little above my head... but something about resonance or something.

That being said.... I made mine 40mm.

P.S. I just set my personal record. 2700 feet. Still had FULL video signal. It was the control that couldn't keep up.

 

[yjander]

I read that it could be any length... so long as it's NOT 29mm (That's the length of each "leg"). The article was a little above my head... but something about resonance or something.

That being said.... I made mine 40mm.

P.S. I just set my personal record. 2700 feet. Still had FULL video signal. It was the control that couldn't keep up.

awesome. I have not really gotten to do nice range test yet. This weekend I am going to the mountains so I can test in a nice open area. But in the small testing I have done, i got to 2200 feet and my RC control is what goes out as well. So next thread, how to make awesome antennas for the 5.8ghz?!

 

[Matts175]

awesome. I have not really gotten to do nice range test yet. This weekend I am going to the mountains so I can test in a nice open area. But in the small testing I have done, i got to 2200 feet and my RC control is what goes out as well. So next thread, how to make awesome antennas for the 5.8ghz?!

Oh yeah. I just remembered what I was going to tell you...... So once I got out that far... I decided to fly the bird sideways for a minute, to simulate what would happen if the antennas were in a different position. Seemed to make no difference what so ever. So, I'd say it's safe to say that they could go on the front legs or back legs or 1 on each, like you have them.

 

[N017RW]

This is the hallmark of an omnidirectional antenna. Just keep them as close to vertical as is feasible. This matches the vertical
polarity of the controller antennas.

 

[yjander]

Oh yeah. I just remembered what I was going to tell you...... So once I got out that far... I decided to fly the bird sideways for a minute, to simulate what would happen if the antennas were in a different position. Seemed to make no difference what so ever. So, I'd say it's safe to say that they could go on the front legs or back legs or 1 on each, like you have them.

that's awesome. I am going to give a try this weekend for sure!!! I'm excited to be in the mountains away from all the WI-FI!!

This is the hallmark of an omnidirectional antenna. Just keep them as close to vertical as is feasible. This matches the vertical
polarity of the controller antennas.

That's good news. Just keep them vertical and let it fly.

 

[Matts175]

I was bored, so I stole the antennas off of my TP-Link router. They are 2.4ghz 5dbi. It actually got 2-300 feet less. I couldn't even make it to my lake. So, back to the home made ones.

 

[N017RW]

Antenna gain is obtained by shaping or steering or directing the 'beam' of energy in a way to make the signal stronger in a particular direction or location. This is the opposite of omnidirectional which radiates in all directions equally.
Those antennas changed the radiation pattern in a way not beneficial to the way you were flying.
This is a general statement so I hope you can grasp my point.
Think of it like focusing the beam of a Maglite flashlight.
So just cause an antenna boasts gain does not mean it will be beneficial in all cases or applications.

 

[Matts175]

Antenna gain is obtained by shaping or steering or directing the 'beam' of energy in a way to make the signal stronger in a particular direction or location. This is the opposite of omnidirectional which radiates in all directions equally.
Those antennas changed the radiation pattern in a way not beneficial to the way you were flying.
This is a general statement so I hope you can grasp my point.
Think of it like focusing the beam of a Maglite flashlight.
So just cause an antenna boasts gain does not mean it will be beneficial in all cases or applications.

Yup. I completely understand. This was just out of shear boredom. LOL

 

[N017RW]

You got it!

 

[RubiconLon]

Great thread. Just got some parts in and can't wait to build my antennae. It's been down for 3 weeks now.

Question tho...
When you solder the extra bare copper on, are you making an L shape out of the stem, then making the T? It's what it looks like if I'm following correctly. My ADD gets the best of me...