Substance
- Transmission Channel
- Transmission Line Equivalent Circuit
- Line Impedance (Zo) / characteristic impedance (Zo)
- Frequency (HF = RF = Radio Frequency)
- There are 2 types of transmission channels
- SWR (Standing Wave Ratio)
- SWR is divided by 3
- DW DISTRIBUTION CABLE (DROP WIRE)
- Vertical Terminal Block Function
1. Transmission Channel
Examples: connecting cables/wires, etc.
Function: to transfer energy from one point to another.
Transmission Line Equivalent Circuit
Consist of :
- resistor (R)
- capacitor (C)
- indicator (L)
- conductance (G)
Transmission Line Equivalent Circuit
Line Impedance (Zo) / characteristic impedance (Zo)
Measured at each point with the same distance:
Frequency (HF = RF = Radio Frequency)
Frequency Level Ladder :
- EHF (Extremely High Frequency)
- SHF (Super High Frequency)
- UHF (Ultra High Frequency)
- VHF (Very High Frequency)
- HF (High Frequency)
- MF (Medium Frequency)
- LF (Low Frequency)
- VHF (Very Low Frequency)
- EHF (Extremely Low Frequency)
There are 2 types of transmission channels:
- Balanced Channel (parallel): twin lead channel and open wire channel
- Coaxial (coax) channel.
International System of Units Ladder
Physical Example of Transmission Channel
Twin Lead
Open Wire
Coaxial
L&C Value for Transmission Line
Information :
? = permeability of the material
? = ?o ?r
?o = absolute permeability
?o = 4? 10-7 H/m
? = permittivity of the material
? = ?o * ?r
? = 8.85 - 10-12 F/m
SWR (Standing Wave Ratio)
Standing wave comparison
SWR is divided into 3:
- Voltage = NSWR : Vmax / Vmin (taken from RMS value)
- Current = ISWR : Imax / Imin
- Impedance = RSWR : Zl / Zo
Zl : load impedance
Zo : characteristic impedance
So, SWR = Vmax/Vmin = Imax/Imin = Zl/Zo
DW (Drop Wire) Distribution Cable
Drop Wire Illustration
Information:
RPU Functions:
- For the primary cable connection from the central
- Test site to localize the disturbance.
- The RPU is located adjacent to the telephone exchange in the MPF room.
Vertical Terminal Block Function
This circuit is installed on the RPU on the customer side where the primary cable is, the capacity of the vertical terminal block is:
- Terminal block with a capacity of 25 pairs of cable cores
- Terminal block with a capacity of 50 pairs of cable veins
- Terminal block with a capacity of 100 pairs of cable veins.
By using jumper wire, the vertical terminal block is connected to the horizontal terminal block. The horizontal terminal block is all cables coming from the central terminated on the horizontal terminal block which has 100 pairs of cable veins and is installed in the RPU.