Antenna Physics

This section will distill several equations regarding antenna theory and connect the dots using words wrapped around the concepts to enable a complete understanding of antenna theory --- for any technical level.

Part 1: The vast difference between electron flow and electric current/displacement flow in a conductor.

To distinguish and visualize the difference between Electron flow and electric current/displacement in a conductor we use the Newtons Cradle instrument --- often considered a toy. It is used to demonstrate transmission line logic including how waves of electric current propagate in a conductor, impedance mismatch, reflected waves, etc. etc.etc.

A. Basic mechanics of wave propagation in a conductor.

Watch this video noting that one bearing is launched at a second resulting in the launched bearing coming to a stop and the second accelerating to the same speed/energy level as the first. Video clip 1 bearing slow. The concept here is, when a bearing is launched at a second stationary bearing that weighs the same, the first will come to rest exactly the depth of compression plus decompression which is approximately 10 nano-inches and the energy from the first will be transferred to the second. The displacement current was probably close to 700MPH. Think of the momentum/velocity as the magnetic energy and the compression the electric field. Look at 1 bearing of 5. Each bearing is accelerated contacting the adjacent, compressing decompressing individually and passing the energy to the next while coming to a stop almost in place.

Sweep of coax balance

 

Coax balance at 1MHz

Coax balance at 2MHz

Coax balance at 5MHz

 

Coax balance at 30MHz

Coax balance at 10MHz

Coax balance at 50MHz

Coax balance at 500KHz

 Coax balance at 10KHz

Coax balance at 100Hz

Coax balance at 20Hz

 

Coax balance at 20MHz

Coax balance at 15MHz

Coax balance at 10MHz

KN5L PROBLEM VF PRO 1

KN5L problem 2

 

Coax loss 20MHz 41ft RG#316 measure source and load

Coax loss 10MHz 41ft RG#316 measure source and load

Coax loss 1 MHz 41ft RG#316 measure source and load

Coax loss 1 kHz  41ft RG#316 measure source and load

Coax loss 100 Hz 41ft RG#316 measure source and load

Coax loss  20 Hz  41ft RG#316 measure source and dest

DC pulse total 41ft 31ft RG316 and 12ft RG174

 

Sweep proof of 50R coax balanced media

.5wl grounded line 1

Mike 3 .5wl perfect ground

 

Radiation resistance of wire antenna web.docx

Radiation resistance of wire antenna.docx

A LEVEL 1 LOGICAL RENDITION CALCULATING RADIATION RESISTANCE.docx

.5wl TLT 1968 K9AXN.docx

.5wl TLT 1968 K9AXN

Hand written Radiation resistance of 1/4wl dipole  Scan20230422 160210.jpg

Scratch Design a 1/4wl Dipole

Scratch Design 1/4wl Dipole img  Scan20230428 102324.jpg

CALCULATE CAPACITANCE OF STRAIGHT WIRE:

See page 586 for equation and 609 for table and K factor

 

Video clip 1 bearing slow

Video clip good 1 bearing slow

Video clip 1 bearing 5 total slow

Video clip 3 bearings slow

 

Video Clip of Surge Current as voltage is applied to 54 foot wire. 

 

Schematic update for surge impedance 

Schematic update 2 for surge impedance

 

Measuring the surge impedance with inadequate ground

Measuring the surge impedance and velocity factor of a single wire

 

Measuring the surge impedance of 75 ohm coax with scope probe on feed point and end of coax 

 

Single wire snapshot of surge impedance 

Part 1 final 6  

END FED DISTRIBUTED AND LUMPED

CENTER FED DISTRIBUTED AND LUMPED

Surge impedance in space

Inverted V and effect on feed line

INVERTED V JPG

COAX

New coax logic chart 1 

New coax logic chart 2

BALANCE SIMULATOR FOR COAX

COAX RG174 12 SINGLE ENDED termination

COAX RG!&$ 12 BALANCED termination  

COAX SWEEPP 20Hz to 20MHz PROOF

COAX SWEEP 20Hz TO 20Mhz proof Zo does not increase at low frequency

DC PULSE TO 36' total 12' RG174 and 24' RG316.