ANET1553 Users Manual
27
3.1.8.2 Transformer Coupling
Transformer Coupling
utilizes a bus coupler that contains
an isolation transformer and isolation resistors. Transformer
Coupling extends the stub length to 20 feet and provides
electrical isolation, better impedance matching and higher
noise rejection characteristics than Direct Coupling. The
electrical isolation prevents a terminal fault or stub
impedance mismatch from affecting bus performance.
Figure 3-18 Stub Coupler
Connecting to the bus using Transformer Coupling requires a Coupler for each
subsystem/terminal device and proper termination on the bus.
Figure 3-19 Transformer Coupling
Aircraft or Lab Cable
Bus Coupler
78Ω Termination
Bus Coupler
(Bus B)
A B
AIM Module
Bus Coupler
(Bus A)
78 Ω Terminators
Stub Length 20 Feet Max
Bus is actually in
coupler
A B
Test Terminals
Figure 3-20 Transformer Coupling
