I tried steak first....let me start over with porridge. The picture of a wave is in-correct, as is modern antenna theory because it is based on Maxwell’s equations. Draw an arrow to the right. Label it E for electric field. Now draw a arrow pointing up thru the middle of the right arrow. Label this perpendicular arrow B for magnetic field. This is how electric and magnetic fields are normally related to each other. Now clamp down on the electric field so it cant move. Now right where the fields intersect...put a wrench on the magnetic field. Now with your hands..start turning the magnetic field. It doesn't matter which way. As you rotate the field...it will be easy at first...but as you get to 90 degrees where the magnetic field and electric field are parallel....that requires the most torque......after 90 degrees, the force required to complete the rotation tapers off at 180 degrees....half turn. Now......let go of the wrench. What happens? The magnetic field will rotate back to it normal position, with the same energy you put into it. Now recock the magnetic field. BTW...90 degrees is the half cock and 180 degrees is full cock or just cock. After cocking the field.....pick up both fields and and set them on a conductor. Now let the both fields go.....what happens in the conductor? As the fields uncock...it will induce a current and voltage in the conductor. This is what a dipole does. During the 180 degree input to a dipole, it sets up this cocked reversed magnetic field. If you stop the input signal right at 180 degrees......that cocked field will stay they forever. Now...if we reverse the current....all the fields will break at the origin. The origin is the feed point of the dipole. This causes two half spherical waves to propagate from the sides of the dipole at the speed of light. One goes left, the other right. The waves stay cocked, because there is no medium that the fields can relax in. It will take another half cycle to build another wave on the dipole. During this time there is nothing being emitted from the diploe. So the dipole takes 180 degrees to establish the field...emits it in two halves....Then takes another 180 degrees to make a new field and emit. The antenna only emits at a very short instant every 180 degrees. So the dipole and the radio waves are a one half chunk system. It puts out one half spins. Then nothing. Another half spin. Then nothing. A radio wave has 1/2 spin.........where have I heard this before?
The receiving dipole works in reverse. When the wave is absorbed by the receiving antenna...the antenna is charged up with the reversed magnetic field(it takes 180 degrees of time to charge). This is the first half sine at receiver input.It will take 180 degrees for the magnetic field to relax in the receiving dipole. This gives the second half of sine to receiver. This happens during the dead space time. As it relaxes in the receiving dipole.......it re-emits half of the received power back out into space. It also loses a little power in the resistance of the antenna......SO a little less than half of the RECEIVED power gets to the radio receiver. The antenna only gets one half of the wave, then nothing for half wave...then the OTHER half of the wave. The 2nd half wave to the receiver is the other side of the wave, Because the transmitting dipole reversed its waves because of input sine feeding it. There is a full sine going into and out of antennas, but the wave between them is half waves with dead space between them.
The way to add power in a electric system is 1/2 at a time. The way to add power in a rotational system is 1/2 at a time.
Electric and magnetic fields are always rotating perpendicular to each other(natural state). It is the angular momentum that balances these fields. It is angular momentum that causes the perpendicularly of the fields. You must study free gyroscopic properties to understand these fields. Once you know how these fields are formed from the origin(area between feed point), you will see that both fields are cocked......and since both are 180 out from each other they appear normal......but they are cocked and loaded.
The receiving dipole works in reverse. When the wave is absorbed by the receiving antenna...the antenna is charged up with the reversed magnetic field(it takes 180 degrees of time to charge). This is the first half sine at receiver input.It will take 180 degrees for the magnetic field to relax in the receiving dipole. This gives the second half of sine to receiver. This happens during the dead space time. As it relaxes in the receiving dipole.......it re-emits half of the received power back out into space. It also loses a little power in the resistance of the antenna......SO a little less than half of the RECEIVED power gets to the radio receiver. The antenna only gets one half of the wave, then nothing for half wave...then the OTHER half of the wave. The 2nd half wave to the receiver is the other side of the wave, Because the transmitting dipole reversed its waves because of input sine feeding it. There is a full sine going into and out of antennas, but the wave between them is half waves with dead space between them.
The way to add power in a electric system is 1/2 at a time. The way to add power in a rotational system is 1/2 at a time.
Electric and magnetic fields are always rotating perpendicular to each other(natural state). It is the angular momentum that balances these fields. It is angular momentum that causes the perpendicularly of the fields. You must study free gyroscopic properties to understand these fields. Once you know how these fields are formed from the origin(area between feed point), you will see that both fields are cocked......and since both are 180 out from each other they appear normal......but they are cocked and loaded.
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