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Chapter 7 - Analyzer Mode
AMA 310/UMS V21.0
Figure 7-4 Level measurement of a 6.4-MHz-QAM-carrier with approx. 60 dBµV in the analyzer
7.4
Freezing of the Spectrum
By selecting
FREEZE
the current spectrum can be freezed. In this state, the menu item
FREEZE
is
shown inverted. If the menu item
FREEZE
is selected once more, the analyzer picture will be
constantly updated again.
7.5
MAX-HOLD Function
By the menu item
MAX HOLD
the Max-Hold function is activated. The menu item is then shown
inverted. If the menu item
MAX HOLD
is selected once again, the function is deactivated again.
Figure 7-5 Activation of the MAX-HOLD function in the real-time analyzer
In the MAX-HOLD operation, the spectrum is only updated if the level between two measurement
cycles has increased. Particularly when searching ingress disturbers this function is of crucial
importance, as they often occur only for a very short time.
As the spectrum is continuously (real-time!) determined within the instrument by AD converter
sampling, even shortest ingress peaks can be identified and shown reliably, even if they occur
between to screen updates.
Apart from the inverted representation of the
MAX HOLD
menu item there is on the top right in the
graphics display also a reference to the activated MAX-HOLD function for screen shots and
documentation purposes: