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Model Three - Operation Manual
Press the
F
1
F
1
(ENTER)
key to start the Relative Spectrum measurement.
The new Zero Reference remains in the Model Three’s nonvolatile memory
even when the Model Three is turned off. This enables you to measure the
level’s relative change at a later time. To perform a new Transmission test
at any time, confirm that
TRANSMISSION
is set to
ON
in the
MEASUREMENTS SETUP
menu and then press the
SPECT
SPECT
6 PQR
key. The Model
Three performs a Spectrum Scan and compares it to the reference data.
Press the
__
and
keys to move the marker frequency.
The Model Three displays the transmission measurement. The reference
level indicates
Δ
dB to show the difference between the current Scan Level
and the Zero Reference scan. In the example above, a 6 dB loss is seen
with the transmission measurement.
Channels in the Base Channel Plan that are not
active on your system have a transmission
indication near 0 dB, because there was no
signal to be changed. A User Plan can be
configured with only active channels by deleting
the unused channels (see Chapter 4: Setup,
Channel Plan, Edit User Plan). This provides a
transmission scan with all active data.
The Span function does NOT operate when the
Model Three is in the Transmission mode. For
normal (absolute value) Spectrum Measurements,
set the Transmission selection to OFF.