A really good video I happened across.

[The DB]

This video, while long, shows many aspects of antennas and transmission lines. If you want to understand antenna systems in general, this is a great place to start. If you want you can skip past the first six and a half minutes or so as they just introduce the guy who is presenting the video.




The DB

 

[KD2GOE]

Vary cool!

 

[Riverman]

This video, while long, shows many aspects of antennas and transmission lines. If you want to understand antenna systems in general, this is a great place to start. If you want you can skip past the first six and a half minutes or so as they just introduce the guy who is presenting the video. The DB

Am enjoying this video, DB.
Having a little trouble though with the comment, "Everything here is applicable to coax as well" given what he is using and coax are apples and oranges in appearance, materials and design. Can you nelp me see this clear?

 

[bob85]

OUTSTANDING, even better than the shive wave machine,

im only half way through and he's visually demonstrated lots of things we have talked about in the past,

1/4wave inverters
1/2wave mirrors
conjugate match
what happens to reflected power
why your watt meter can show more forward power than the transmitter outputs
why gainmasters won't take the power that sirio claim due to high vswr on the coax above the stub
current & voltage distribution on antennas & feed-line
velocity factor
dielectric loading

he's mentioned what causes lines to radiate,
im hoping he unbalances that line ,

the guy is a superb teacher,
reading articles is great but something you can actually see with your own eyes that proves the antenna & transmission-line theory you read about is the dogs bollocks,


This needs to be a sticky right at the top of the list.

thanks DB

 

[The DB]

Am enjoying this video, DB.
Having a little trouble though with the comment, "Everything here is applicable to coax as well" given what he is using and coax are apples and oranges in appearance, materials and design. Can you nelp me see this clear?

Pretty much anything you can do with a balanced transmission line you can also do with coax. Looks mechanics and such aside, what is important is what is happening electrically. Almost everything that he did with this parallel line can also be done with coax, and it works exactly the same way, aside from moving around all those nifty little lights he uses to show voltage, current, and energy.


The DB

 

[Marconi]

Thanks DB. I recall sometime back seeing this video or one like it.

I didn't learn much from the video at the time, but I did see demonstrated...if you really want to improve the signal from your whizzbang CB monoplane antenna...use more metal and get a beam.

reading articles is great but something you can actually see with your own eyes that..............

I agree Bob.

For me, being able to see with my eyes thru modeling...is why I took up trying to learn more. At least it was my hope to possibly be able to see what I otherwise had to try and imagine from words.

I had doubts with the words form some of my CB buddies and I didn't understand much from the writings published by antenna notables.

I believe a picture is truly worth a 1000 words. I will be watching this again.

 

[bob85]

Eddie,

imho anybody wanting to understand antennas & feed-lines MUST understand everything that this guy demonstrates,

its the visualisation of articles such as maxwells reflections deals with,

i agree 100% it is very difficult to get people to undertstand in their minds eye the concepts shown here with just words on a forum even with links to respected sources,

a video of such principles is worth way more than 1000 words,

in one video this guy demonstrates 90% of what we have talked & argued about over the last 12+ years,

he blows the made up laws of physics out the water,

i wish somebody had posted this years ago,

sirio & vortex should pay attention & stop BSing us with mickeymouse power ratings for stub matched antennas.

 

[Riverman]

Pretty much anything you can do with a balanced transmission line you can also do with coax. Looks mechanics and such aside, what is important is what is happening electrically. Almost everything that he did with this parallel line can also be done with coax, and it works exactly the same way, aside from moving around all those nifty little lights he uses to show voltage, current, and energy.


The DB

Got it.
The video is fantastic. Best thing I've come across on this site. His visual demonstration of the principles makes them so much easier to understand.

Thanks so much!

 

[PA629]

Good video. Just wish it had information that applied to the 11 Meter band. You know, the Twilight Zone of radio communication.

 

[StrangeBrew]

Good video. Just wish it had information that applied to the 11 Meter band. You know, the Twilight Zone of radio communication.

As we all know physics work differently on 11 meters, he would have to start from scratch with a new video to cover it.

 

[M0GVZ]

Good video. Just wish it had information that applied to the 11 Meter band.

Why, does radio behave differently there?

 

[PA629]

Why, does radio behave differently there?

Absolutely. Unless he has another video covering it, he never even mentioned antenna "audio gain"............