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USER'S MANUAL. TV EXPLORER HD +
Speed of sweep can be modified for terrestrial TV signals. To that end, press
shortly the key [17] MEASUREMENT CONFIGURATION. On the menu "Configuration"
it will appear the option "Sweep". Entering in this option you can switch between "Fast"
for a quick sweep of the spectrum or "Accurate" for a slower sweep. This option will only
appear when you're working with terrestrial TV signals, therefore the led "T" on the front
panel must be lighted.
The frequency range displayed (called span from hereon) can also be altered
using the horizontal cursors
screen frequency range in Spectrum Analyser mode between Full (the entire band),
500 MHz, 200 MHz, 100 MHz, 50 MHz, 32 MHz, 16 MH and 8 MHz (the latter one only
in terrestrial band).
A vertical broken line, called marker, appears on the spectrum display to identify
the tuned frequency.
One of the applications of the TV EXPLORER
Analyser is in the search for the best orientation and position of the receiving antenna.
This is particularly important in UHF. Because such frequencies are involved, with
wavelengths ranging from 35 cm to 65 cm, if the antenna is shifted only a few
centimetres, the relationship between the picture, chrominance and sound carrier
frequencies change, affecting the quality of the picture in the receiver.
If there is an excess of sound carrier, tearing or 'moiré' may appear on the screen
due to the frequency beats between the sound, chrominance and the picture
frequencies.
If there is a chrominance carrier defect, then the television colour amplifier must
function at maximum gain, which could result in noise appearing all over the television
screen with points of colour that disappear when the saturation control is reduced; in an
extreme case, loss of colour may occur.
5.16.1 Markers
(Only in Spectrum Analyser mode). The marker in red colour indicates the central
frequency or tuning frequency, which can be moved by means of turning the rotary
selector
[1] as well in channel as in frequency tuning mode
When monitoring a digital signal spectrum also appears two additional markers in
white colour, which indicate the bandwidth of the digital channel (See previous Figure).
12/2011
[6] key. Therefore enables selecting the displayed
HD +
operating as Spectrum
[24].
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