UNAOHM
26
EP2500 (Rev. 0)
Figure 9
Spectrum analyser display
7.13.1
Video Filter
The video filter improves the quality of the display of the signals that are either made up of or similar to
noise, such as digital carriers. The video filter is enabled or disabled by means of the utility routines.
See section 8.2.2 for more details).
7.14
SPECTRUM EXPANDED FUNCTION
The EXP (expanded) function (see
Figure 10
) makes it possible to "zoom" the frequency zone around
the marker. Access is possible only through the spectrum analyser mode, pressing the multifunction key
EXP
. To adjust the extent of the zoom press the multifunction key
SPAN
, then carry out the adjustment
by means of the Shaft Encoder. Indicatively, in the VHF/UHF band the minimum frequency deviation
(maximum detail) may be used to view the colour subcarrier / audio/stereo carrier zone, while the
maximum deviation includes some TV channels.
The OSD indication is the same as that of the spectrum analyser mode, except for RANGE, on the lower
left, substituted by MORE; pressing the additional
(36)
in fact, access is given to the three special ratio
measurements Video/Audio, Carrier/Noise ratio, digital channel power, described in the following
chapters.
NOTES
for
SPECT
rum
and
EXP
anded
functions:
•
The frequency range is slightly extended beyond the limits quoted. It should be noted, however, that
beyond those limits the exploration linearity is not under control any more; especially in the UHF
band, beyond 900 MHz, the carriers may show some tilt which may appear evident.
•
When in pause and each time the tuning is changed, it is normal to view that the spectrum is
refreshed on the screen.
•
The curve shown is calibrated, but maximum accuracy may be guaranteed only in the
MEA
sure
mode.
•
In the SAT band,
N
(narrow) setting there is no numerical level reading.
•
For the SAT frequencies, the marker frequency accuracy is in tens of kHz; therefore in the
N
(narrow) band, it may not lie on the
cusp of a CW even if it has been perfectly tuned.
Spectrum, SAT band
1740 SPANOFF pr 00
SAT 13V 22k C M 20
BW W
MEA
EXP
TV
50.5 dBuV
