Agilent Technologies 8510C, Operating And Programming Manual

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Netw ork Analyzer System Description
Measurement Accessories
Source Output-to-T est-Set Input Signal Cable
Use a high quality source-to-test-set cable set to minimize loss and instability . The preferred
source-to-test set cable set is part n um b er 08513-60009. This set has has a 3.5-mm male
connector on one end and the 3.5-mm female connector on the other. These cables ha v e low
loss and are rugged.
T est P ort Return Cables
High qualit y cables, attenuators, and adapters to connect b et w een the test set p orts and
the device under test are essen tial to ac hiev e accurate, rep eatable measuremen ts. W orn or
unstable cables and connectors increase measuremen t errors due to directivit y , mismatc h,
and frequency resp onse eects. Chec k cables and connectors regularly and replace them as
necessary .
T est p ort return cables used with the net w ork analyzer system m ust b e durable and stable,
and care is required to a v oid damaging them. Cables can b e destroy ed b y b ending with to o
tight a radius. Because ev en with careful use, cables w ear out ev en tually , treat all cables as
consumable items to b e replaced as often as necessary . The most imp ortan t c haracteristic of
all cables is minimum magnitude and phase c hange b et w een mov emen ts (exures) of the cable.
Replace a cable when unacceptable magnitude and/or phase c hanges o ccur when the cable is
mov ed.
The standard recommended cables, in go o d condition, m ust b e used for detailed p erformance
v erication of the analyzer system. These cable sets ha v e low insertion loss, go o d electrical
match, and high return loss, and they are stable in use. F or other applications, an y high
quality cable set can b e used.
Extension Lines
External signal path extension lines connected to the test set rear panel EXTENSION A and
EXTENSION B connectors are used to balance the reference and test signal path lengths
according to the p ort 1 and p ort 2 connections to the test device. Balancing the reference
and test signal path lengths can b e imp ortant when making measuremen ts requiring highest
accuracy . Signal path balance is less imp ortant when using the syn thesized sw eep er in the
step sw eep mo de.
The extension lines are pro vided in t w o lengths: long, whic h has sev eral lo ops, and short.
Figure 3-7 sho ws the recommended conguration of theses extension lines for the standard
coaxial test sets.
Principles of Operation 3-11