Tks guys, I found exactly same info researching in this forum!

Now I'm planing to build an crossair to use with Cloverleaf....I think it will work better than dipole + biquad......but I may be wrong, let's try!

Originally Posted by jmaurin

Tks guys, I found exactly same info researching in this forum!

Now I'm planing to build an crossair to use with Cloverleaf....I think it will work better than dipole + biquad......but I may be wrong, let's try!

Those two combinations have totally different characteristics. Cloverleaf will reject interference better so that would be good if you are flying around buildings. If you are talking about straight line distance dipole + BiQuad will give you much more range. It all depends on where you are flying and how much range you need.


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Originally Posted by RC Man

Those two combinations have totally different characteristics. Cloverleaf will reject interference better so that would be good if you are flying around buildings. If you are talking about straight line distance dipole + BiQuad will give you much more range. It all depends on where you are flying and how much range you need.


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I'm not planing to go further than 10~15Km max. Currently I have an inverted V in my skywalker.....and a simple omni antenna in RX (the one that came with RX) and another patch antenna, which I'm planing to replace. With this current configuration, I have a lot of glitchs and interference while flying......that why I like to change,...I just don't know where to go. I usually fly in open space (not building) with airplane only (no drones for now).

Since my last post, I performed a 25km distance with excellent video quality

Need help here.
I make my own DIY dipole antenna and biquad mesured for 1280mhz channel
All the dimension match, but i got terrible range (~900m). No short on active and ground.
Btw, I know the interference between Crossfire (915mhz) and 1.2 video system, that why i use 5.8 relay to place the 1.2 VRX far away from Crossfire TX, but it's not the reason why I got only 900m on FPV

Since i found some copper tubes here, I'll use with my feed. My question is: copper tube is soldered into reflector, ok.....but cable shield should be soldered into copper or isolated from copper? Once is soldered to copper tube, it will be automatically soldered to reflector too.

I can't make a good one

I've tried two antennas, both are getting SWR of 3:1.

I'm making for 1.160Mhz. section length is 6,42cm and element spacing (heigth) is 3,21cm. I'm using 26x26cm reflector.

The first antenna has 63,25mm as section length.....then, I measured and found SWR of 1.4:1 at 1.050Mhz (mor or less). Then I tried another antenna with smaller section lenght....now with 62,3mm.....but still no good SWR at 1.160Mhz What could be wrong?
For element, I'm using 1.5mm copper wire.

Originally Posted by jmaurin

I can't make a good one

I've tried two antennas, both are getting SWR of 3:1.

I'm making for 1.160Mhz. section length is 6,42cm and element spacing (heigth) is 3,21cm. I'm using 26x26cm reflector.

The first antenna has 63,25mm as section length.....then, I measured and found SWR of 1.4:1 at 1.050Mhz (mor or less). Then I tried another antenna with smaller section lenght....now with 62,3mm.....but still no good SWR at 1.160Mhz What could be wrong?
For element, I'm using 1.5mm copper wire.

Are the screws to mount plastic frame with bowtie to spacers metal? On the pic looks that way.
Also maybe this is only on pic but I`m seeing that your bowtie is not made from one wire piece.
If above is true and not my pic misread - replace metal screw with plastic ones, and make bowtie from one wire piee.
You can solder it, but any soldering joints have impact on antenna performance (even solder blobs not rounded or to big).

Be patient

When I was making my 2370Mhz biquad it took me 6 bowtie`s before it was almost spot on.
The hardest with this antenna is that you can`t fine tune it. The only way is trial and error.
But if you have some analyzer and 3d printer you only need patience

Originally Posted by nikram77

Are the screws to mount plastic frame with bowtie to spacers metal? On the pic looks that way.
Also maybe this is only on pic but I`m seeing that your bowtie is not made from one wire piece.
If above is true and not my pic misread - replace metal screw with plastic ones, and make bowtie from one wire piee.
You can solder it, but any soldering joints have impact on antenna performance (even solder blobs not rounded or to big).

Be patient

When I was making my 2370Mhz biquad it took me 6 bowtie`s before it was almost spot on.
The hardest with this antenna is that you can`t fine tune it. The only way is trial and error.
But if you have some analyzer and 3d printer you only need patience

Tks, I'll try to remove those screws and test. The bowtie is made from one wire only, solder is just for coax.

This 3D printed bowtie frame influence a lot! I figured out with antenna analyzer. It changes the resonant frequency.

Originally Posted by jmaurin

I can't make a good one

I've tried two antennas, both are getting SWR of 3:1.

I'm making for 1.160Mhz. section length is 6,42cm and element spacing (heigth) is 3,21cm. I'm using 26x26cm reflector.

The first antenna has 63,25mm as section length.....then, I measured and found SWR of 1.4:1 at 1.050Mhz (mor or less). Then I tried another antenna with smaller section lenght....now with 62,3mm.....but still no good SWR at 1.160Mhz What could be wrong?
For element, I'm using 1.5mm copper wire.

What frequency does it resonant now at? You should be able to adjust from that with a bit of math. If your at 1.1ghs then need to be done a wee smaller.

Originally Posted by Martin Y

What frequency does it resonant now at? You should be able to adjust from that with a bit of math. If your at 1.1ghs then need to be done a wee smaller.

That`s true, I had same problem. After I made perfect bowtie, adding some 3d printed spacers moved tune a little bit up.
With this frame effect could be bigger.

So If I was you @jmaurin - Make new element on frame, analyze and note element length, VSWR, S11, R.
To low resonant freq - shorten element (for ease of calculation 5mm shorter) and note parameters and difference between elements lenght .
With this data you should be able to calculate how much more you need to shorten to achieve your freq.
Pay attention how you measure element length, take into consideration wire thickness.

Tks for the tips!

I've modified and it's pretty good now! Not perfect, but a wey better!

Originally Posted by jmaurin

Tks for the tips!

I've modified and it's pretty good now! Not perfect, but a wey better!

In my opinion it`s really, really good
Congratulations.

Originally Posted by jmaurin

Tks for the tips!

I've modified and it's pretty good now! Not perfect, but a wey better!

Nice, still need to make a bit smaller to raise the frequency