Ferrite antenna: Is the signal pulled in like a magnet?

[Mike(Mont)]

i don't even know how to ask this question. Is the signal there before you point the ferrite rod at it? Or is it created only after the ferrite is pointed at it?

[Geo]

Ferrite don't create any signal.
Because too many magnetic lines are forced to go through it, we say that it is a kind of amplification.

[Mike(Mont)]

I'm not so sure about it. As I understand it, the flux lines are gathered through the ferrite. And this might create a conduit for the signal to travel along--a magnetic highway like what happens with the sun at times. I don't know but there is something going on there for sure.

I even think the human body has some sort of signal draw. It's like the lines are not there until they get developed, either from walking near the target or waving the antenna in that direction a few times like stroking a piece of iron with a magnet. Then the lines are pulled to the receiver and form the signal. Maybe.

[Mike(Mont)]

i know this probably isn't the exact same thing and a loctor works on a much lower scale, but if you've seen one of those plasma globes, when you put your finger near it the pathway forms. Probably the same process with a lightning rod. The path is created--it is not there to begin with. And OMG yes, with the "L" word L-rod.

[Mike(Mont)]

Don't know if this is any help.

www.sparkbangbuzz.com/els/magbdcst-el.htm

[WM6]

Originally Posted by Mike(Mont)

Don't know if this is any help.

www.sparkbangbuzz.com/els/magbdcst-el.htm

Interesting explanations but probably not based in existing physics.

Changeable magnetic field (as generated per detectors coils) is not the same as radio wave.
"copper wire around the house and driving it with the speaker output" does not emit radio waves, it only create changeable magnetic field (mostly inside) loop. Similar or equal as so called "ground loop" coil used in prospecting and earth survey. Neither can emit radio waves.

One simple experiment can prove us that electromagnetic field and radio waves are not the same. If you wrap your Walkie Talkie in Alu foil it can stop to emit and receive radio waves, but if you wrap detector coil (in fact most of those coil are already wrapped) in the same foil, you cannot stop magnetic field to go (out and in), through Alu foil.

Magic word here is resonance and phase. You cannot emit radio waves without resonance creating phase between radio wave components, on other side, detectors changeable magnetic field emitting and receiving coils in general does not need (PI coil par example) any resonance to emit EM field and by following phase we can only distinguish metal parts instead of propgate. There are exception (Enigma p.e.). And some detectors design are based on radio waves instead of changeable magnetic field (GPR devices, some mine detectors..).

But radio waves are composed from magnetic component too. This why ferrite antenna works. As Geo explain it aspirate nearby magnetic (as all ferromagnetic in general) field lines and this way strengthen radio signal at given location:



More reading:

http://physics.stackexchange.com/que...-really-genera

[Mike(Mont)]

Of course I don't know WTF I'm talking about! I am just trying to think what some call "outside the box" but I prefer "outside the walls of the lab maze". When i was about four years old I loved the TV show "Mighty Mouse". My mom bought me a Mighty Mouse shirt with a cape on it. I asked her "Does this mean I can fly now?" She replied "Yes'" So I jumped off the back porch. Wow what a shock of disbelief when I hit the ground! i really thought I was going to fly.

[Mike(Mont)]

I'm sure the skeptics will say "Some things never change." Well it was 18 years later before I buitl my own hang glider and flew off the Snake River Canyon years ahead of Evel Knieval. I like one of his quotes "All the money in the world can't get you into Heaven, and it won't buy your way out of Hell..."

I'm surprised Geo is the only brave one to wade in here on this thread.