HP 8753E Service Manual

Cable Test
The load match error term is a good indicator of cable problems. You can
further verify a faulty cable by measuring the reflection of the cable. Perform
an Sll l-port calibration directly at port 1 (no cables). Then connect the suspect
cable to port 1 and terminate the open end in 50 ohms.
Figure 9-l shows the return loss trace of a good (left side) and faulty cable.
Note that the important characteristic of a cable trace is its level (the good cable
trace is much lower) not its regularity. Refer to the cable manual for return loss
specifications.
CHl
Sll log MAG
5dB/ REF 0 dB I-: -28.426 dB
CHl
Sll
log WAG
5 dB, REF 0 dB I-: -15.524 dE
START
030 000 MHZ
STOP 6 000.000 000 MHz
Figure 9-1. Typical Return L OSS
Traces of Good and Poor Cables
START
030 000 MHZ
STOP 6 000.000 000 MHz
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HP 8753E Specifications

General

Brand	HP
Model	8753E
Category	Measuring Instruments
Language	English