Sorry to spoil the soup a little bit! There's one design flaw. You can't use random wire lengths as you want to make sure feedpoint impedance is aprox. 50 Ohms. A hint: use odd multiples of quarter wave length as your feed wire lenght. This is really important!
I discovered his channel several months ago. I loved his channel because of his passion. I was shocked when I discovered that he was actually not alive anymore
It is probably a good idea to mention the implications of polarisation linear to linear and linear to circular. The short answer I suggest is to use linear to circular for aerobatic flying. This will have lower gain but a more consistent signal for all attitudes of the quad.
Great video!!! The only thing is that when I type lets say c/2.4/4 on the browser address line I get a formula for a cup!!! Nothing to do with the calculation of the coax cable measure I have to strip! Any idea why I cant get what you get on your screen! Thanks buddy!!!
Wouldn't it be better to make a dipole like you find inside a rubber ducky? Should have better performance than the monopole you are making here right?
Hi I have broken my anttena in my drone it work on 5.8ghz in my receiver is have dual anttena and the length of exposed wire in around 10 mm should I use the same in transmitter or 12.9 mm please aswer
So, the rest of the lenght is not important, only the un-shielded part? so if I wanted to tune it to a specific freq closer to 5.6, just do the math, cut to length, and should in theory be better off?
Left field question but, why do we choose a 1/4 length antenna? On what occasion would we want to have... say a 1/2 wave length? or even a full wave length? I'm just curious I am studying for my ham license. I want to know as much as I can.
There is one big conceptual error: you have to make the other half of the dipole, i.e. the shielding should extend for the same length as the corem but downwards... As presented here, the antenna would work very badly and possibly burn u the Tx.
hello, I wonder how I can make a sma antenna for UHF in the range of 638 to 692? can you help me, I can not find any explanatory video. the material of a GHz antenna is the same as a UHF? Thanks if you can reply and sorry for English, I'm using a translator.
Sad to read that we lost this kind teacher. RIP If anyone else know the answer to my question I would be pleased to know, otherwise I will just try to do it.
@@gnyger If it's a simple wire then yeah I guess so. It's the length of the antenna that matter in this case. If your 2.4ghz antenna is around 31mm then yeah I believe you can just trim it to 12.92mm
I'v made more than a few of these and if you use 50% larger dia. wire you will increase range by 1/3 on average. Keep it long and tune in field. Lots of folks will solder these on incorrectly or have too much shield cut off either end so field tuning works best. That large solder joint at the SMA will decrease it's effectiveness. Shield over it with TV coax cable with the main conductor and it's inner jacket removed. If you do go with larger awg wire keep it 1-2 mm shorter.
if the length at the tip is more exposed than 12.3mm, lets say 20 mm. will it get worse reception. seems like the more exposed the more it would pick up. can u help me understand? great videos btw.
not much, but there is some loss at 5.8GHz, so you shouldn't go beyond 10 or 15 cm unless it will really make a better placement for the active / top end
thank you so much for this, I made my micro fpv quad so much lighter, it's amazing how much more lift and punch I have to where I can do split 'S's over obstacles. Thank you so much again!
Thanks for the great video! I'm actually interested in the one on the taranis will build one asap. Do you have any experience in using a half wavelength antenna on the taranis instead of a quarter? Would it have any benefits over the quarter like increased range? Or would that not work at all and fry some electronic component in the radio?
It would have been helpful if you included the units in your calculations. The unit of the speed of light is m/s, and its value is something around 299792458. Rough estimate. The unit of the frequency is 1/s, and the value is something around 5.8*10^9 (Giga = 10^9). Now, when we divide the speed by the frequency, we get (0.3*10^9 m/s) / (5.8*10^9 1/s) which equals to 0.3/5.8 ms/s, which gives us a wavelength of 0.051688 m or 51.688 mm. Since this video is about a quarter-wavelength, we have to divide it by 4 to get the mentioned 12.92 mm. The whole calculation confused me a little bit, and if there's somebody else who felt the same way, I hope my comment could fix that at least to a slight extent.
Brilliant!... Let Google size my antenna! LOL... Actually some pretty .."Smart-Cookie" s#!t ! ..I've been having trouble getting my stuff to listen "as-is" this channel (in conjunction with a couple of others) ..has given me the confidence to undertake the necessary aftermarket mods ... much thanks bro
WOOw ! la pire antenne qui peux exister pour plusieurs raisons, je déconseille ce montage que l'on trouve partout sur la toile. J'estime le retour vers l’émetteur à 20% de perte
Thanks, JC. I was looking up something completely unrelated to drones and your video still was a result. You're going to live forever!
Sorry to spoil the soup a little bit! There's one design flaw. You can't use random wire lengths as you want to make sure feedpoint impedance is aprox. 50 Ohms. A hint: use odd multiples of quarter wave length as your feed wire lenght. This is really important!
Are you referring to the 12.92 measurement or the length of the whole antenna?
Still going back to your videos for help mate! Hope your doing good up there
RIP JC. You teach me many drone related things.. you fly away too early.. Rest In Peace..
Alexander Ribchansky it's difficult to watch isn't it
Yes, still can't believe that JC gone.. Still watch his videos with great interest. ;(
Alexander Ribchansky yea, he still leaves a wealth of information
Alexander Ribchansky what happened to him?
I discovered his channel several months ago. I loved his channel because of his passion. I was shocked when I discovered that he was actually not alive anymore
It is probably a good idea to mention the implications of polarisation linear to linear and linear to circular. The short answer I suggest is to use linear to circular for aerobatic flying. This will have lower gain but a more consistent signal for all attitudes of the quad.
You nailed it. Sorry I forgot to mention this but I absolutely agree. Thanks for sharing.
here I am finding your vid which is a great help since I chopped the active element on my linear antenna on my whoop. This is your legacy bruh.. RIP
Great video!!! The only thing is that when I type lets say c/2.4/4 on the browser address line I get a formula for a cup!!! Nothing to do with the calculation of the coax cable measure I have to strip! Any idea why I cant get what you get on your screen! Thanks buddy!!!
your videos are still teaching me thanks JC RIP
How do you measure for a 2.4GHz 5dB?
Wouldn't it be better to make a dipole like you find inside a rubber ducky? Should have better performance than the monopole you are making here right?
Hi I have broken my anttena in my drone it work on 5.8ghz in my receiver is have dual anttena and the length of exposed wire in around 10 mm should I use the same in transmitter or 12.9 mm please aswer
So, the rest of the lenght is not important, only the un-shielded part? so if I wanted to tune it to a specific freq closer to 5.6, just do the math, cut to length, and should in theory be better off?
Left field question but, why do we choose a 1/4 length antenna? On what occasion would we want to have... say a 1/2 wave length? or even a full wave length? I'm just curious I am studying for my ham license. I want to know as much as I can.
There is one big conceptual error: you have to make the other half of the dipole, i.e. the shielding should extend for the same length as the corem but downwards... As presented here, the antenna would work very badly and possibly burn u the Tx.
how about a video on how to purchase and replace the bearings on an e Max red bottom?
Great idea. I'll do a video on that very soon.
Diameter size cable coaxial antennas brother?
hello, I wonder how I can make a sma antenna for UHF in the range of 638 to 692? can you help me, I can not find any explanatory video. the material of a GHz antenna is the same as a UHF? Thanks if you can reply and sorry for English, I'm using a translator.
What a pleasure that I found a JC video while researching antennas. Still taking me to school. :0)
Can I just buy 2.4 ghz antennas and trim off the lenght to 12.92 mm?
I bought the wrong antennas for 2.4 and I need 5.8 for fpv.
Sad to read that we lost this kind teacher. RIP
If anyone else know the answer to my question I would be pleased to know, otherwise I will just try to do it.
@@gnyger If it's a simple wire then yeah I guess so. It's the length of the antenna that matter in this case. If your 2.4ghz antenna is around 31mm then yeah I believe you can just trim it to 12.92mm
I'v made more than a few of these and if you use 50% larger dia. wire you will increase range by 1/3 on average. Keep it long and tune in field. Lots of folks will solder these on incorrectly or have too much shield cut off either end so field tuning works best. That large solder joint at the SMA will decrease it's effectiveness. Shield over it with TV coax cable with the main conductor and it's inner jacket removed. If you do go with larger awg wire keep it 1-2 mm shorter.
if the length at the tip is more exposed than 12.3mm, lets say 20 mm. will it get worse reception. seems like the more exposed the more it would pick up. can u help me understand? great videos btw.
Any chance you can prematurely burn out a vtx using this method? Because of heat dissipation through antenna?
Man, your videos have so much information i am not prepared, cant wait so finally be able to follow your videos! Thx for helping me setup my taranis !
What is that little cylinder metal shape is on the top of the antenna?
What is the purpose of having it?
Thanks
what determines the dbm/dbi value on an antenna?
Nice video, would the gain of the antenna be higher if you have a full wavelength antenna? So better range?
would it be possible to solder a 31.22 mm unshielded wire straight to the plus of the transmitter ?
kubbur possibly, as I remember some rxs have a wire of the correct length just sticking out, no coax.
On many linear antenna there is a little metal tube acting as mass. Isn't that required?
Its not required. After you remove it just recheck the length of your signal wire.
How to downgrade basic dipole to monopole antenna without ground plane 😬
can you put black heatshrink over the whole thing without it affecting the range?
Yes!
No velocity factor in calculation?
Why 1/4 of the wave and not 1/2?
is that considered monopole antenna ? if so, can you explain plz why we dont need a ground plane. thanks a lot
Sharaf Malebary He died in accident, no more replies or new video's.
Might be. it is ok i think we cn work things out with Mr. Google's help.
Nice video. Is there any way you can go over the antenna mod for the taranis? love the videos.
Yea no problem.
Project Blue Falcon Please too
love you JC.
Could I do this with half length? What effect would that have?
Is there a benefit making a specific band antenna?
Does the length of the coax part matter?
not much, but there is some loss at 5.8GHz, so you shouldn't go beyond 10 or 15 cm unless it will really make a better placement for the active / top end
thank you so much for this, I made my micro fpv quad so much lighter, it's amazing how much more lift and punch I have to where I can do split 'S's over obstacles. Thank you so much again!
how to make Polarized Patch antena?
Ive started using these instead of clovers on micros.
Thanks again JC
Hello can those TV antenna works lol
Hi can some one tell me if I can build the same antenna for my spektrum radio?
late to the party, but yes you can. Just use the length specified for 2.5GHz somewhere in the video
Great video. This antenna type, which gain can have?
I'm honestly not sure what the gain is. I just use them on small and close range multirotors.
Thank you for doing this video Jc!!
No problem at all
Thanks bruh wish you where still making vids
Good video mate. G’day from Australia.
Thanks for the great video!
I'm actually interested in the one on the taranis will build one asap. Do you have any experience in using a half wavelength antenna on the taranis instead of a quarter? Would it have any benefits over the quarter like increased range? Or would that not work at all and fry some electronic component in the radio?
I'll do a video on it.
Built a whip today with this video. Thanks JC. :(
It would have been helpful if you included the units in your calculations.
The unit of the speed of light is m/s, and its value is something around 299792458. Rough estimate.
The unit of the frequency is 1/s, and the value is something around 5.8*10^9 (Giga = 10^9).
Now, when we divide the speed by the frequency, we get (0.3*10^9 m/s) / (5.8*10^9 1/s) which equals to 0.3/5.8 ms/s, which gives us a wavelength of 0.051688 m or 51.688 mm.
Since this video is about a quarter-wavelength, we have to divide it by 4 to get the mentioned 12.92 mm.
The whole calculation confused me a little bit, and if there's somebody else who felt the same way, I hope my comment could fix that at least to a slight extent.
These videos are great I was so sad to read about his death.
Yea, he was my number one reference for my first build a year ago. I still come back to his videos and learn new things. He is truly missed.
Thanks again JC
add one more wire and make it a dipole, performs a bit better
As always, such a good and usefull video! Thx
Brilliant!... Let Google size my antenna! LOL... Actually some pretty .."Smart-Cookie" s#!t ! ..I've been having trouble getting my stuff to listen "as-is" this channel (in conjunction with a couple of others) ..has given me the confidence to undertake the necessary aftermarket mods ... much thanks bro
very good !
Amazing
Thanks. Very helpful. This is going to save me a lot of money. :)
I'm all about saving money
nice video, I also do these to my micro's
Really helpful 👍👍👍
Very good.
nice, thanks
Awesome thx!
Many errors in the video. People already point them out in comments below.
nice video buddy 🖒🖒
WOOw ! la pire antenne qui peux exister pour plusieurs raisons, je déconseille ce montage que l'on trouve partout sur la toile. J'estime le retour vers l’émetteur à 20% de perte
Wow, youtube some how unsubscribed me from you! damn you youtube.
But nice! I just did this, this afternoon good timing! :)
I was watching to the point where you used profanity.. NOT good..
Amazing