
Service
Theory of Operation
A2 Controller and A3 Switch Driver Board Theory
The mother and daughter boards provide the bias for the switching paths for the various ports to the Reflection or Transmission ports. The front panel display contains an LCD that indicates the switched ports. A particular test port (1 through 8) can be in one of three states. The three states are:
•Switched to the forward path
•Switched to the reverse path
•Terminated in 50 Ω
When a port is not connected, it is automatically terminated in 50 Ω. Only one test port can be connected to any one reflection port and only one test port can be connected to any transmission port at any given time.
The test set consists of eight 1x2 switches and six 1x4 switches. The 1x2 switches divide each of the input ports (1 through 8) into two separate paths.
All switches are electromechanical and are biased according to the necessary switching path. A user interface through the GPIB and parallel ports converts the necessary input signals from the user to the necessary control signals to control the switching paths.
A4 Front Panel Display Theory
The front panel display consists of an LCD. The LCD is divided into two lines of text. The first line indicates which of the twelve ports are connected to the forward path. The second line indicates which of the twelve ports are connected to the reverse path. Control signals and DC power are provided by a cable connected to the main switch board.
Connector Replacement
The 50 Ω
8 | Agilent Technologies Z5623A Option H48 |