A25 And A26 Test Port Couplers; A23 And A24 Detectors (E8363B And E8364B Only); 30-Db Fixed Attenuators (E8362B Only) - Agilent Technologies E8362B Service Manual

PNA Series Microwave Network Analyzers Theory of Operation
E8362B, E8363B, E8364B Signal Separation Group Operation
Figure 5-3 Signal Separation Group, Standard Analyzer

A25 and A26 Test Port Couplers

The test port signal goes into the through-line arm of the couplers, and from there to the
test ports and the DUT. The coupled arm of the couplers carries the signal reflected from or
transmitted through the DUT, to the receiver (through a front panel jumper for
Option 014) for measurement. The coupling coefficient of the directional couplers is
nominally 15 dB over the full frequency range.

A23 and A24 Detectors (E8363B and E8364B Only)

The A23 and A24 detectors sense the R1 and R2 reference signal levels and provide
feedback to the ALC circuitry on the A16 test set motherboard.

30-dB Fixed Attenuators (E8362B Only)

The 30-dB fixed attenuators are placed in the reference signal paths to provide isolation.
The source power output is sufficiently stable over this frequency range that ALC feedback
is not necessary.
Service Guide E8364-90026 5- 17