A20 If Multiplexer Board - Keysight N5221A Service Manual

PNA Series Microwave Network Analyzers Theory of Operation
N5221A/22A Receiver Group Operation
The A23 mixer brick sends the EXT TSET DRIVE LO OUT signal to a rear-panel connector for use with an
external test set. This same output connector on the A24 mixer brick is terminated.

A20 IF Multiplexer Board

This assembly provides pulse modulation capability and routes the IF signal out through the rear panel
connectors for external use and routes external signals in through rear panel connectors to be included in
the signal processing.
In this assembly, on 4-port models, the R1, R2, R3, and R4 reference signals are combined to create one
reference signal, R. On 2-port models the R1 and R2 reference signals are not combined.
The analog IF signals (A, B, C, D, and R for 4-port models and A, B, R1, and R2 for 2-port models) are sent to
the A12 SPAM board where they are converted to digital information.
Rear Panel Interconnects
The A20 IF multiplexer board includes the following rear panel interconnects.
PULSE I/O A DB-15 female connector. Pin assignments are listed in Table 5-5 on page 5-22.
Service Guide N5222-90001 5-21