The Transmission Lines circuit board provides students with the theory and measurement skills required to implement and test communications transmission lines. Courseware covers the principles and operational characteristics of transmission lines, conducting transmission line measurements under transient (step testing) and sinusoidal steady-state conditions, and valuable foundational information on the theory and practice of time-domain reflectometry (TDR), as well as impedance matching and transformation.
The circuit board uses two 24-meter (78.7 feet) RG-174 coaxial cables which can be used separately or connected end-to-end. Each line has five probing points that permit observation and measurements of signals along the line, using an oscilloscope. Two generators are provided to study the transmission line behavior: a step generator that produces a 50-kHz square-wave voltage for transient behavior testing, and a signal generator that produces a sinusoidal voltage of variable frequency (5 kHz – 5 MHz) for steady-state behavior testing. Each generator has several BNC outputs providing different output impedances. A load section, consisting of a configurable network of resistors, inductors, and capacitors, permits connection of different load impedances to the receiving end of each line.
- Characteristics of Transmission Lines
- Transmission Line Measurements Under Transient (Step Testing) and Sinusoidal Steady-State Conditions