Feeders
Course Guide Topics
Purpose
Types of feeder
Characteristic Impedance
Parallel Conductor Line
Preventing Line Radiation
Balanced Line
Coaxial Line (Coax) (1)
Coaxial Line (Coax) (2)
Waveguide
Velocity Factor
Velocity Factor (Contd)
Terminated Line (Matched Case) (1)
Terminated Line (Matched Case) (2)
Terminated Line (Unmatched Case)
Standing Waves (1)
Standing Waves (2)
Standing Waves (3)
Line Loss (1)
Line Loss (2)
Matching
Matching – Quarter Wave Transformer (1)
Matching – Quarter Wave Transformer (2)
Lines as Tuned Circuits
Open Circuit
Short Circuit
Stubs
Stub Characteristics
Antenna Tuning Units – ATU
Balance/Unbalance
Baluns
Typical Baluns
1:1 Current Balun
4:1 Voltage Balun
1:1 Voltage Balun
4:1 Transmission Line Voltage Balun
Preventing Line Radiation
By using two conductors the electromagnetic field from one is balanced everywhere by an equal and opposite field from the other – resultant field is zero
There is no radiation from the feeder with
openwire
or
ladderline
– they are
balanced
lines
Course Guide Topics
Purpose
Types of feeder
Characteristic Impedance
Parallel Conductor Line
Preventing Line Radiation
Balanced Line
Coaxial Line (Coax) (1)
Coaxial Line (Coax) (2)
Waveguide
Velocity Factor
Velocity Factor (Contd)
Terminated Line
(Matched Case) (1)
Terminated Line
(Matched Case) (2)
Terminated Line
(Unmatched Case)
Standing Waves (1)
Standing Waves (2)
Standing Waves (3)
Line Loss (1)
Line Loss (2)
Matching
Matching – Quarter Wave Transformer (1)
Matching – Quarter Wave Transformer (2)
Lines as Tuned Circuits
Open Circuit
Short Circuit
Stubs
Stub Characteristics
Antenna Tuning Units – ATU
Balance/Unbalance
Baluns
Typical Baluns
1:1 Current Balun
4:1 Voltage Balun
1:1 Voltage Balun
4:1 Transmission Line Voltage Balun