Feeders

• This is the simplest voltage balun, consisting of two coils of wire connected as shown
• The coils may use an air core or a ferrite core
• Current flowing through the lower coil induces an equal and opposite voltage in the upper coil
• The primary circuit contains N turns and the secondary 2N, so the input impedance is
• Z_L(N ÷ 2N)² = ¼ Z_L

Course Guide Topics

1. Purpose
2. Types of feeder
3. Characteristic Impedance
4. Parallel Conductor Line
5. Preventing Line Radiation
6. Balanced Line
7. Coaxial Line (Coax) (1)
8. Coaxial Line (Coax) (2)
9. Waveguide
10. Velocity Factor
11. Velocity Factor (Contd)
12. Terminated Line
    (Matched Case) (1)
13. Terminated Line
    (Matched Case) (2)
14. Terminated Line
    (Unmatched Case)
15. Standing Waves (1)
16. Standing Waves (2)
17. Standing Waves (3)
18. Line Loss (1)
19. Line Loss (2)
20. Matching
21. Matching – Quarter Wave Transformer (1)
22. Matching – Quarter Wave Transformer (2)
23. Lines as Tuned Circuits
24. Open Circuit
25. Short Circuit
26. Stubs
27. Stub Characteristics
28. Antenna Tuning Units – ATU
29. Balance/Unbalance
30. Baluns
31. Typical Baluns
32. 1:1 Current Balun
33. 4:1 Voltage Balun
34. 1:1 Voltage Balun
35. 4:1 Transmission Line Voltage Balun