I built an 8 segment version of this antenna a couple of weeks ago to replace a generic wideband scanner antenna I had been using. Immediate 35% increase in the number of aircraft being received each day. The range in a couple of directions is about 100nm better.
Před 10 lety+3
'Muricans using the metric system properly. Got to love it! Peace and love!
The formula I like is: 300 / frequency in Mhz = wavelength in meters. Or: 300 / Wavelength in meters = frquency in Mhz. Those formulas work well enough. I always make my antennas slightly long and shorten the antenna as needed till I get a suitable SWR.
The radio frequency signals in each 1/2 wave section are kept in the same phase by the cross connections of the hot conductors and shields. This coordination of phases are what produces the gain in the overall antenna. They are all working together like multiple rowers of a boat rowing in the same direction instead of against one another.
Yes, impedance is AC reactance (resistance to AC) plus DC resistance. The figure is used of course because RF signals are a form of Alternating Current. Darren seems so enthused about radio stuff in general I reckon he might do well to get a Ham licence if he hasn't already - the training is very useful - more so as you go up the licence scale.
As a ham radio operator some of the terms you used are not quite right but all in all it was not too bad of a show. For the next installment I would get a tech advisor that is a ham or in the radio field.
Uh, "Yagi-Uda" - not Udan. Udan is an airport development plan, according to the 'pedia. Or a Japanese soup noodle food thing. Whereas Shintaro Uda was one of the inventors of this type of directional array.
The best option for "getting into all this radio stuff" is getting an amateur radio license. Since getting my license I have learned TONS about radio. It's tons and tons of fun. You should go to a meeting of your local amateur radio club. They can answer any questions you have and help you get your license. They may even do license testing. You can find club listings on the ARRL website. If you have any questions I would be more than happy to answer them.
The symbol for wavelength, whether it is light, sound, or vibration is Lambda. it is the 11th letter of the greek alphabet. ANd it is lower case cuz the upper case symbol means different things. It looks like an X with the top right leg chopped off.
16:00 If you don't have an atmosphere the electromagnetic interference from the space will still affect our transmission. So we are better off with an atmosphere.
For receiving RF 75ohm coax is ok but not the best if you plan on transmitting RF 50ohm coax like RG-58 or RG-8 is what you need also LMR-400 is great for building collinear antennas I have built many 2m/70cm HAM Band collinear sticks placed inside of PVC to keep a tidy build PS love the videos and you many want to try building a J-Pole or Super J-Pole KC9WSC
Hi there, i would like to know if at the tip of the collinear antenna there is something that conect the center with the braid conductor, cause i see they left all disconected, it is corect? May somebody use a 50/75 ohm resistor or just do a "short circuit" from central pole and the other pole ?
This is for receiving only, you do not use it to transmit, so not relevant to what they have made The main problem is they didn't explain it clearly enough or test correctly, leaving some people probably confused.
***** Here's an idea: mount a raspberry pi to a drone with an RTL SDR dongle attached. Get the pi to collect adsb packets in flight and stream them over WiFi!
I did that on an AR.Drone (which runs Linux and has USB, so no Raspberry Pi required): lemondronor.com/blog/indexphp/2013/4/cheap-ads-b-on-amateur-drones
Regarding what's said at the 7m5s mark, would using a longer antenna damage the equipment it's connected to? I've killed THREE working Alfa AWUS036H (1W, 5dBi antenna) after having plugged in a longer / higher gain (9dBi) antenna for a few minutes.
Kinda depends what the setup is but in general no, not if you are using the proper ohm cable for the antenna and test your SWR or Standing Wave Ratio with an SWR meter, that's the amount of impedance mismatch on the antenna elements. If the SWR is too high you WILL COOK the radio equipment because that feeds back into your radio equipment as reflected power instead of being transmitted. Also, as long as you aren't transmitting and just passively listening it won't reflect that power back into your equipment. As an example, if you are using 75 ohm coax on a 50 ohm system you will toast your equipment...
lol - and what was the resulting antenna working like? Did it work? I would expect you did detect some far away planes but then they faded away when they came closer to your location? The point is: planes are not only moving on the surface, i. e. in 2 dinemnsional pane, and they are not always in the line of sight, Planes do move in 3dimensional apace, so you usually don't want to have signal that much concentrated and picky about the right heigth. Especially as you won't get further than the point when the planes do climb over the horizont, meaning your line of free sight. If they are below that line you won't get them anyways. Another negative aspect is, that there is not only one single plane sending at a time. If the planes don't receive signals from each other they may send their informations more than one at a time. And thus the information packets would "collide", they get lost. I did build some stacked antenna with only 3 elements (even if it was no collinear antenna) and got detection radius of about 100..160 miles out of it. Range was depending strongly on the weather conditions and was heavily blocked by geological obstacles in the line of sight. So 3 elements did already get me either very close to the horizon with my RTL-SDR stick, maybe that really was horizon already, where the planes would disappear from the line of sight due to the curve of earth surface. But I got better results when I split the receiption area into multiple segments. That is because then I had by far less packet collisions and therefore I got more continous receiption, including the area the area directly over my antenna location.
Darren.. what up man. Bring the Dronage pwnage brah. Would like to know what you think of demodulating the signal and seeing if you could take control of its controls, while jamming the original signal? Maybe a dual antenna setup, one for taking control, which would follow the Drone and the other for the jamming.. ;p Epic evil Drone take over
PRETTY SURE your RTL-SDR "Software Defined Radio" uses 50 ohm coax not 75 ohm cable TV coax. Your antenna would work better if it was made out of 50 ohm coax because 75 ohms causes an impedance mismatch... I know for certain if you tried transmitting with that antenna on a 50 ohm system you'll TOAST your equipment!
just saying him saying bout its not the llength that matters its how you use it and when they use it with the drone they end up using two and being sucessful
So they built the thing, said they would go out and test it, came back another day (after the video cut to different clothes)... and quietly changed subject. Next episode this, next episode that, drones, yada yada... so the antenna didn't work then?
Darren Will be first to say,amount of fails are more then then amounts of wins,but that how we learn,anyways i know antenna got used in other projects one pointing at a hill for the airplane tracking,other one he was carrying around on his back ninja style, then got stuck to the top side of his car.
Hi Darren what I love bet about you today is you look like you put on sum pounds since the last video I watched. I wish I could put it on like that! Haha love your guys show. !
My dad took my wifi pineapple away from me, now that would be okay if he actually lived in the same house, but we have never really lived together and i spent a big part of the money i got for christmas on it, now he won't give it to me or give me the money for it... since i live in sweden i had to pay 48$ extra for shipping. Sorry for wasting your time if you read this far but i just wanted to say it.
I guess, but he never tried to be a father before and now he's just making it worse... About the legality of it here, i looked it up befoe ordering it and its legal.
its never been an 'exact science' when it comes to antenna. Too many factors and more than often its almost never more than .5 DB. The lower the freq the longer the antenna thats obvious but more takes into account like time of day, sun spots...etc.
Shannon, you are adorable, beautiful, and the #2 reason I watch the show. Sorry, but hacker shtuff is #1. BTW, my wife wants to know where you get your shirts.
The hacks should always be number 1. My looks should never be the reason why anyone watches the show :). I got my shirts from sharkrobot.com and teeturtle.com
I built an 8 segment version of this antenna a couple of weeks ago to replace a generic wideband scanner antenna I had been using. Immediate 35% increase in the number of aircraft being received each day.
The range in a couple of directions is about 100nm better.
'Muricans using the metric system properly. Got to love it! Peace and love!
The formula I like is: 300 / frequency in Mhz = wavelength in meters. Or: 300 / Wavelength in meters = frquency in Mhz. Those formulas work well enough. I always make my antennas slightly long and shorten the antenna as needed till I get a suitable SWR.
You've finished your antenna ?
The radio frequency signals in each 1/2 wave section are kept in the same phase by the cross connections of the hot conductors and shields. This coordination of phases are what produces the gain in the overall antenna. They are all working together like multiple rowers of a boat rowing in the same direction instead of against one another.
The "totally rounding" on the speed of light constant is 10^3 off!!! That's good rounding skills right there.
Shannon: What is K?
Darren: It's Potassium. Lol.
LOL! [Ar] 4s1
75Ohm is the cable's *impedance* not resistance. There is a difference.
+dellagd 75 not 750
That's what he said. 75. ...As in 75Ohm
Yes, impedance is AC reactance (resistance to AC) plus DC resistance. The figure is used of course because RF signals are a form of Alternating Current. Darren seems so enthused about radio stuff in general I reckon he might do well to get a Ham licence if he hasn't already - the training is very useful - more so as you go up the licence scale.
***** He didn't say 750 hm, but 75Ohm. That's an "O" not a zero.
what is the main difference between impedance and resistance?
As a ham radio operator some of the terms you used are not quite right but all in all it was not too bad of a show. For the next installment I would get a tech advisor that is a ham or in the radio field.
A dielectric is a material that cannot conduct electricity, but does support electromagnetic fields and can be polarized.
I gotta say, that was agonizing to watch. :(
You should get your ham radio license
yes it's not w it's lamda, love your show!!
I knew there was a lamda in there somewhere :)
I posted the same comment. This is why one should read the comment section BEFORE posting a comment. :)
The turbo button limits the clock speed of the cpu because some applications wouldn't work when the clock speed wasn't set correctly.
Uh, "Yagi-Uda" - not Udan. Udan is an airport development plan, according to the 'pedia. Or a Japanese soup noodle food thing. Whereas Shintaro Uda was one of the inventors of this type of directional array.
It's λ = c / f ! Awesome episode!
I really want to get into all this radio stuff!
The best option for "getting into all this radio stuff" is getting an amateur radio license. Since getting my license I have learned TONS about radio. It's tons and tons of fun. You should go to a meeting of your local amateur radio club. They can answer any questions you have and help you get your license. They may even do license testing. You can find club listings on the ARRL website.
If you have any questions I would be more than happy to answer them.
@@purplemutantas the best way to learn amateur radio is to get a shortwave receiver. Listen to the experts, then get your licence.
im crying inside
The symbol for wavelength, whether it is light, sound, or vibration is Lambda. it is the 11th letter of the greek alphabet. ANd it is lower case cuz the upper case symbol means different things. It looks like an X with the top right leg chopped off.
I wasted my time at university studying electronics. All I needed to know was the Velociraptor Factor.
16:00 If you don't have an atmosphere the electromagnetic interference from the space will still affect our transmission. So we are better off with an atmosphere.
Tell that to big oil! I keed. I keed *snicker*
For receiving RF 75ohm coax is ok but not the best if you plan on transmitting RF 50ohm coax like RG-58 or RG-8 is what you need also LMR-400 is great for building collinear antennas I have built many 2m/70cm HAM Band collinear sticks placed inside of PVC to keep a tidy build
PS love the videos and you many want to try building a J-Pole or Super J-Pole
KC9WSC
Hi there, i would like to know if at the tip of the collinear antenna there is something that conect the center with the braid conductor, cause i see they left all disconected, it is corect? May somebody use a 50/75 ohm resistor or just do a "short circuit" from central pole and the other pole ?
This is for receiving only, you do not use it to transmit, so not relevant to what they have made
The main problem is they didn't explain it clearly enough or test correctly, leaving some people probably confused.
***** Here's an idea: mount a raspberry pi to a drone with an RTL SDR dongle attached. Get the pi to collect adsb packets in flight and stream them over WiFi!
Funny you should mention that........... ;-)
I did that on an AR.Drone (which runs Linux and has USB, so no Raspberry Pi required): lemondronor.com/blog/indexphp/2013/4/cheap-ads-b-on-amateur-drones
12:20 'portrait-loop-long.mp4' on the screen behind Darren
time to render out portrait-loop-even-longer.mp4
The answer ... about 90% of the time, this is not a good antenna. It is very very picky and a simple spider will often outperform it.
It's an F connector. N connectors are..bigger.
If you don't know the parts of a yagi antenna its probably better to talk about something else!
Regarding what's said at the 7m5s mark, would using a longer antenna damage the equipment it's connected to? I've killed THREE working Alfa AWUS036H (1W, 5dBi antenna) after having plugged in a longer / higher gain (9dBi) antenna for a few minutes.
Kinda depends what the setup is but in general no, not if you are using the proper ohm cable for the antenna and test your SWR or Standing Wave Ratio with an SWR meter, that's the amount of impedance mismatch on the antenna elements. If the SWR is too high you WILL COOK the radio equipment because that feeds back into your radio equipment as reflected power instead of being transmitted. Also, as long as you aren't transmitting and just passively listening it won't reflect that power back into your equipment. As an example, if you are using 75 ohm coax on a 50 ohm system you will toast your equipment...
+darrenkitchen what make of ultra small laptop is that you're using now?
lol - and what was the resulting antenna working like? Did it work? I would expect you did detect some far away planes but then they faded away when they came closer to your location?
The point is: planes are not only moving on the surface, i. e. in 2 dinemnsional pane, and they are not always in the line of sight, Planes do move in 3dimensional apace, so you usually don't want to have signal that much concentrated and picky about the right heigth. Especially as you won't get further than the point when the planes do climb over the horizont, meaning your line of free sight. If they are below that line you won't get them anyways. Another negative aspect is, that there is not only one single plane sending at a time. If the planes don't receive signals from each other they may send their informations more than one at a time. And thus the information packets would "collide", they get lost.
I did build some stacked antenna with only 3 elements (even if it was no collinear antenna) and got detection radius of about 100..160 miles out of it. Range was depending strongly on the weather conditions and was heavily blocked by geological obstacles in the line of sight. So 3 elements did already get me either very close to the horizon with my RTL-SDR stick, maybe that really was horizon already, where the planes would disappear from the line of sight due to the curve of earth surface. But I got better results when I split the receiption area into multiple segments. That is because then I had by far less packet collisions and therefore I got more continous receiption, including the area the area directly over my antenna location.
Would this work? I get an TV Antenna and put an cable with the pineapple wifi with a customed adapter
Wavelength is represented by the lower case Greek letter lambda.
What is the end point connector that is being used? SMA to the antenna? How is it being attached?
he is looking at the prompter :D
Why didn't you guys solder it to the braided wire? It would have created a stronger hold and connection.
Math tip - Google search can search for "speed of light divided by 1090 megahertz" www.google.ca/?gfe_rd=cr#q=speed+of+light+divided+by+1090+megahertz
Darren, you're king of the fkn nerds.
Luv U
Lambda is wavelength. Omega is (2*pi*freq) in electronic engineering.
A high gain antenna as .such needs to be mounted perfectly vertically. Otherwise you lose all the gain on the horizon.
Darren.. what up man. Bring the Dronage pwnage brah. Would like to know what you think of demodulating the signal and seeing if you could take control of its controls, while jamming the original signal? Maybe a dual antenna setup, one for taking control, which would follow the Drone and the other for the jamming.. ;p Epic evil Drone take over
Does the 116mm length include the wire pigtails?
LOL close enough for government work, cheers from DC
Where can I download portrait-loop-long.mp4 from?
RE: 12:22 ;)
DON'T GIVE HER THE KNIFE! lol cool tut thanks guys.
That's the mini-laptop looking thing Darren keeps playing with?
It is a lambada.
The forbidden frequency.
It's actually RG-59, RG-58 is 50 Ohm. RG-59 is the cheaper alternative to RG-6.
Thanks, I goofed on that one :)
September 6th seems pretty far away to be scheduling a brunch. :)
PRETTY SURE your RTL-SDR "Software Defined Radio" uses 50 ohm coax not 75 ohm cable TV coax. Your antenna would work better if it was made out of 50 ohm coax because 75 ohms causes an impedance mismatch... I know for certain if you tried transmitting with that antenna on a 50 ohm system you'll TOAST your equipment!
Speed of light 300Km/s ...LOL!
Anyway nice video!
is it not 10.8cm each length of cable
The symbol for wavelength is lambda, every Half-life fan should know that. λ
and if you've done high school physics (we cover it here in new zealand)
could you put some links to the material listing on ebay please
Put 10 antenna designers in a room and you'll get 20 different opinions. They're all dipolar.
It IS lambda, trust your guts!
you feed your tv with rg-11 or rg-6 not rg-58 that's what hams and cbers use on there radios and it's 50 ohms
It's a lot easier to use this formula λ/2=468/freq in MHz = length in feet.
Next week?!? NOOOOOO
what is the gadget on the table?
which gadget?
***** is it my rich fantasy or is there some umpc like something where u take a look at from time to time. With full querty and a screen?
***** I would also like to know this
Nikolai Domaev I did some quick google searches.; its called an i-mate jasjar.
just saying him saying bout its not the llength that matters its how you use it and when they use it with the drone they end up using two and being sucessful
Lol cause it is Lamda :D i just got my Ham Radio License KK6ZNF
nope go back and re-study its lambda
most people who are in to this love math so ... "yay math!" instead
portrait-loop-long.mp4
So they built the thing, said they would go out and test it, came back another day (after the video cut to different clothes)... and quietly changed subject. Next episode this, next episode that, drones, yada yada... so the antenna didn't work then?
Darren Will be first to say,amount of fails are more then then amounts of wins,but that how we learn,anyways i know antenna got used in other projects one pointing at a hill for the airplane tracking,other one he was carrying around on his back ninja style, then got stuck to the top side of his car.
No special antenna is needed for this, any broadband UHF antenna such as a Discone will work.
Hi Darren what I love bet about you today is you look like you put on sum pounds since the last video I watched. I wish I could put it on like that! Haha love your guys show. !
My dad took my wifi pineapple away from me, now that would be okay if he actually lived in the same house, but we have never really lived together and i spent a big part of the money i got for christmas on it, now he won't give it to me or give me the money for it... since i live in sweden i had to pay 48$ extra for shipping. Sorry for wasting your time if you read this far but i just wanted to say it.
mmm swedish meatballs
yeah atleast i have that to make me happy again :P
BDBD16 no, but because he is worried i will get in trouble i guess. .__.
I guess, but he never tried to be a father before and now he's just making it worse...
About the legality of it here, i looked it up befoe ordering it and its legal.
Pentester, white hat.
Damn math -_- there is software that automatically does all these calculations... or maybe use Excel!
*****, NOLACON 2014 in New Orleans... I believe it's a first for the south. Check it out if you get a chance. Take care, bro.
its never been an 'exact science' when it comes to antenna. Too many factors and more than often its almost never more than .5 DB. The lower the freq the longer the antenna thats obvious but more takes into account like time of day, sun spots...etc.
What a bunch of garbage and poorly presented at that.
I'm using a dipole that I got with a free-view box and I can pick up beacons from 80 miles away
worth watching just for shannon ,she is gorgeous !
@Shannon: Please! Let me see a picture of you in that aluminum foil:p
Unwatchable
73 de ac0v
Was the beginning a hint at what someone said last episode in the comments. Her apparently being pregnant?
Bahahaha, do I look fat? Guess I better keep working out.
Shannon Morse no it's me that's looking fat. It's true - I'm prego!
Shannon Morse No you don't, was just dat darren seemed to want you to tell us something. Guess we'll never know...
RG = Radio Guide.
I already track jets out to 200 nmi
Wth speed of light is not 300km/s it is 300000 km/s
wavelength is lamda
It is a lambda
Or you can just buy the 2 antennas they had showed lol
stopped watching after "that" word
you all fail at explaing antenna therory... ;-P
Shannon, you are adorable, beautiful, and the #2 reason I watch the show. Sorry, but hacker shtuff is #1. BTW, my wife wants to know where you get your shirts.
The hacks should always be number 1. My looks should never be the reason why anyone watches the show :). I got my shirts from sharkrobot.com and teeturtle.com
v=fλ
so
λ=c/f
Shannon tries too hard sometimes.. Seems that way to me anyhow
No, I just get really excited about this stuff. Sorry if you think I'm trying too hard. You'd feel differently if you'd met me.
Shannon Morse
Didn't think you'd actually reply... Now I feel like a jerk.
dee jay no worries. Most folks think I don't read the comments, but we do ;)
Darren put on a couple pounds.
It comes and goes. I blame the ale and lager. Can't fault a man for that!
128k subscribers :p