About Db Rules - Fluke DSX-600 Technical Reference Handbook

DSX-600 CableAnalyzer
Technical Reference Handbook

About dB Rules

For some test limits, the tester ignores the PASS/FAIL result from
some tests when a measurement is less than a specified value. For
example, the return loss measurement is not evaluated against
the limit at frequencies where insertion loss is less than 3 dB. This
is the 3 dB rule.
When a measurement is not evaluated against a limit, the tester
shows an for the result. On the plot for that measurement, the
limit line is black where the result is not evaluated against the
limit, as shown in Figure 45. When you upload the results to
LinkWare PC, N/A shows for the result.
The next sections summarize the dB rules. Tables 3 and 4 show the
dB rules that apply to each test and the test limits that use the
rules. For more information, see the Knowledge Base on the Fluke
Networks website.
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