Planar IT-14 Operating Manual
IT-14
DVB-T SIGNAL ANALYZER
OPERATING MANUAL
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22.04.2011
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TABLE OF CONTENTS
1 GENERAL INFORMATION....................................................................................................................... 4
1.1 INTRODUCTION.........................................................................................................................................4
1.2 SAFETY PRECAUTION................................................................................................................................4
2 GENERAL PRESCRIPTION AND PRINCIPLE OF OPERATION............................................................ 4
2.1 FUNCTION................................................................................................................................................4
2.2 ENVIRONMENTAL CONDITIONS...................................................................................................................5
2.3 PACKAGE CONTENT..................................................................................................................................5
2.4 SPECIFICATION ........................................................................................................................................6
2.5 DESIGN AND OPERATION OVERVIEW ..........................................................................................................7
2.5.1 Principle of operation ..................................................................................................................... 7
2.5.2 Block diagram ................................................................................................................................7
2.5.3 Component arrangement ............................................................................................................... 8
3 PREPARATION FOR OPERATION ......................................................................................................... 8
4 OPERATION PROCEDURE..................................................................................................................... 8
4.1 CONTROLS AND INDICATORS .....................................................................................................................8
4.2 PREPARATION FOR MEASUREMENT............................................................................................................8
4.3 MEASUREMENT PROCEDURE.....................................................................................................................9
4.3.1 General information........................................................................................................................ 9
4.3.2 LEVEL measurement mode......................................................................................................... 10
4.3.3 SCAN measurement mode .......................................................................................................... 12
4.3.4 RIPPLE measurement mode ....................................................................................................... 13
4.3.5 SPECTRUM measurement mode................................................................................................ 14
4.3.6 MER/BER measurement mode.................................................................................................... 14
4.3.7 CONSTELLATION measurement mode...................................................................................... 16
4.4 DATA MANAGER .....................................................................................................................................16
4.4.1 General information...................................................................................................................... 16
4.4.2 Channel plan manager................................................................................................................. 16
4.4.3 Data log manager......................................................................................................................... 18
4.5 SETUP ...................................................................................................................................................21
4.6 SELF-TEST.............................................................................................................................................21
4.7 IDENTIFICATION ......................................................................................................................................22
4.8 BATTERY OPERATION .............................................................................................................................23
4.9 PC COMMUNICATION ..............................................................................................................................23
4.9.1 General information...................................................................................................................... 23
4.9.2 Software installation..................................................................................................................... 23
4.9.3 USB driver installation.................................................................................................................. 23
4.9.4 PC communication launch ........................................................................................................... 23
4.9.5 Firmware updating ....................................................................................................................... 24
4.9.6 Channel template editing ............................................................................................................. 25
5 MAINTENANCE...................................................................................................................................... 26
6 TROUBLESHOOTING............................................................................................................................ 26
7 STORAGE............................................................................................................................................... 27
8 TRANSPORTATION............................................................................................................................... 27
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1 GENERAL INFORMATION
1.1 Introduction
This operating manual is intended for introducing the design, functions, and basic instructions related to
operation and servicing of IT-14 (Analyzer).
IT-14 is designed for testing and adjustment of television and broadcasting distribution networks as well
as of separate components of such networks, or other electronic devices. The Analyzer allows measurement
of channel level, parameters of TV signal with analog and digital modulation of DVB-T standart.
The Analyzer can be used both in laboratory, powered by an external power source, and in field,
powered by batteries or car cigarette lighter.
The reliability of the IT-14 is ensured by fulfillment of regular maintenance procedures. These
procedures and their intervals are described in Section 5.
In this manual the following abbreviations are used:
ADC - Analog-to-Digital Converter
BER - Bit Error Ratio
CD - compact disk
COFDM - Coded Orthogonal Frequency Division Multiplexing
DVB-T - Digital Video Broadcasting - Terestrial
IF - Intermediate Frequency
LCD - Liquid Crystal Display
MER - Modulation Error Ratio
MPEG2 - Motion Pictures Expert Group
PC - Personal Computer
preBER - BER before Viterbi decoder
postBER - BER after Viterbi decoder
QAM - Quadrature Amplitude Modulation
QPSK - Quadrature Phase Shift Keying
1.2 Safety precaution
Thoroughly inspect the product and carefully read the related documentation to get acquainted with all
the safety markings and instructions before you start to operate the Analyzer.
WARNING Only trained service personnel aware of the hazards involved should perform repair on the
Analyzer.
CAUTION Tuning the Analyzer and replacement of the components that influence the accuracy of
measurements without service personnel is strictly prohibited, since the components used in the Analyzer
are purpose-made and their replacement will result in inaccurate operation of the Analyzer. To exclude the
possibility of mechanical damage to the IT-14, the instructions regarding the storage and transportation
(Sections 7 and 8) of the Analyzer must be observed.
2 GENERAL PRESCRIPTION AND PRINCIPLE OF OPERATION
2.1 Function
The IT-14 offers measurement of the following parameters of analog channels: video carrier level, V/A
ratio, and C/N ratio. For digital channels channel power can be measured. For DVB-T signals IT-14 offers
measurement of reception quality parameters: modulation error ratio MER, bit error ratio BER before and
after Viterbi decoder, erroneous packets after Reed-Solomon decoder counter and constellation diagram. IT14 features automatic defining of the settings (channel frequency, subcarriers number, subcarriers
modulation type, guard interval, code rate, spectrum inversion). The IT-14 can be connected to a personal
computer to access additional modes. The Analyzer allows to measure direct and alternating voltage of the
remote power supply of the TV and broadcasting distribution networks.
The appearance of the Analyzer is shown in Figure 1.1. and Figure 1.2.
Figure 1.1 Figure 1.2
This Operating Manual is made in accordance with the firmware version 13.0.0.4 for IT-14.
2.2 Environmental conditions
Normal operating conditions:
a) ambient temperature (23±5) °С;
b) relative air humidity (55±25)%;
c) atmospheric pressure 84-106 kPa (630-795 mm Hg);
d) voltage transients correspond to installation category CAT. II.
Rated operating conditions:
a) ambient temperature from -10 to 50 °С;
b) relative air humidity not greater than 90% at 25 ºС temperature;
c) atmospheric pressure 84-106 kPa (630-795 mm Hg).
2.3 Package content
The Analyzer package includes:
a) IT-14 .................................................................................................... 1 pc;
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b) Rubber boot ......................................................................................... 1 pc;
c) Li-Ion battery........................................................................................ 1 pc;
d) “F”-”F” adapter ..................................................................................... 1 pc;
e) 12V/1.2A charger................................................................................. 1 pc;
f) Reference card .................................................................................... 1 pc;
g) Opearting manual ................................................................................ 1 pc.
2.4 Specification
Operating frequency range................................................................................ 45 to 900 MHz
Resolution.......................................................................................................... 125 kHz
Channel template............................................................................................... set with PC (section 4.9.6)
Input parameters:
input impedance within operating frequency range:..........................................75 Ohm
input impedance for frequencies up to 50 Hz:...................................at least 200 kOhm
Allowed resulting value of AC input voltage for frequencies over 5 MHz:………......3 V
A
llowed resulting of AC and DC input voltage for frequencies under 100 Hz:.......150V
Level measurement range................................................................................. 30 to 120 dBµV
Measurement level resolution............................................................................ 0.1 dB
Accuracy within 30 – 120 dBµV level range ...................................................... ±1.5 dB
Accuracy at operating temperature ...................................................................±2.2 dB
Measurement channel passband for -3 dB level ...............................................230 ± 60 kHz
Frequency indication.......................................................................................... 6 characters on LCD
Channel number indication................................................................................ 3 characters on LCD
Signal level indication ........................................................................................4 characters on LCD
Input signal modulation
Channel bandwidth .....................................................................................8 MHz
Channel modulation type ............................................................................COFDM
Subcarriers modulation type .......................................................................QPSK, QAM16, QAM64
Subcarriers number..................................................................................... 2k, 4k, 8k
Guard interval.............................................................................................. 1/32, 1/16, 1/8, 1/4
Hierarchical modulation type....................................................................... α=1, α=2, α=4
Code rate..................................................................................................... 1/2, 2/3, 3/4, 5/6, 7/8
Operating channel power range ........................................................................ 60 to 110 dBµV
MER measurement range (for QAM64, code rate 3/4) .....................................18 to 35 dB
MER measurement resolution ...........................................................................0.1 dB
MER measurement accuracy at operating channel power................................ ±2.0 dB
BER measurement range
preBER........................................................................................................ 1.0x10
-2
to 1.0x10
-8
postBER ......................................................................................................1.0x10-3 to 1.0x10
-8
Channel power treshold (postBER less than 2x10-4)
For QAM64, code rate 3/4, SNR=46 dB .....................................................40 dBµV
Frequency auto tuning range............................................................................. ±0.500 MHz
Warm-up time, less than.................................................................................... 5 min
IT-14 powering:
from AC circuit with 100/220V voltage and 50/60 Hz via 12V/1.2A charger;
from external DC source with 10 to 14 V voltage and ripple level no greater than 0.5 V;
from Li-ion battery with 1500 mAh capacity.
Current consumed from external power
source or batteries, not greater than .................................................................0.6 A
Continuous stable operation under normal conditions (when powered by external source)
no less than ..................................................................................................24 hrs
Battery life under normal conditions (1500 mAh battery capacity), no less than 3 hrs
Mean time between failures, no less than .........................................................10000 hrs
Average lifetime, no less than ...........................................................................5 years
Dimensions ........................................................................................................ 193x94x53 mm
Package dimensions.......................................................................................... 255х180х70 mm
Weight................................................................................................................ 0.46 kg
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Weight in package .............................................................................................0.5 kg
2.5 Design and operation overview
2.5.1 Principle of operation
The IT-14 Analyzer is a receiver of DVB-T signals with demodulation of the traffic stream to MPEG-2.
The input tuner is a super heterodyne receiver with triple frequency conversion (auto or manual frequency
tuning). Modulation error ratio MER and constellation diagram are measured in the process of DVB-T signal
demodulation based on vector analysis. Bit error ratio BER in digital stream is determined by means of
analysis of Viterbi and Reed-Solomon decoders operation. Channel power is measured by means of analogto-digital converter after signal detection at output of logarithmic detector of the amplifier of the third IF. Level
of analog channels is detected with peak detector. Power of digital channels and noise level are detected
with average detector. The principle of spectrum analyzer is based on sequential analysis method with
spectrum indication on the LCD display.
The view displayed on the screen in the MER/BER mode DVB-T signals reception quality parameters
measurement is the numeric values of the measured digital parameters (MER, bit error ratio BER before and
after Viterbi decoder and erroneous packets counter after Reed-Solomon decoder). The constellation
diagram mode shows the vector structure of the quadrature components of the demodulated digital signal on
the phase plane. The signal level measurement mode in a frequency point displays for the analog signals:
the numeric value of the signal level, V/A and C/N ratios, for digital signals: the value of the actual channel
power.
2.5.2 Block diagram
The block diagram of IT-14 is shown in Figure 2.5.1.
Low-pass filter
(LPF)
Attenuator
0/20/40dB (A)
Tuner
45-900 MHz
(T)
Band-pass filter
IF2 39 MHz
(BPF2)
Mixer
(M)
Band-pass filter
IF3 10,7 MHz
(BPF3)
Logarithmic gain
amplifier limiter
(LGAL)
Local oscillator
28,3 MHz
(LO)
Band-pass filter
IF2 36,125 MHz
(BPF1)
DVB-T
demodulator
(Dm)
Keyboard
(K)
Nonvolatile
memory
(NVRAM)
Liquid-crystal
display
(LCD)
Power unit
(PU)
Control unit
(CU)
Analog-to-digital
converter (ADC)
Signal detector
(SD)
Amplifier
0/11dB (Amp)
Figure 2.5.1
After the low-pass filter (LPF), the input signal if necessary is strengthened by the wide-band amplifier
(Amp) or reduced by the attenuator (A). Then the signal is converted into the second IF 39 MHz in level
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measurement mode or 36.125 MHz in DVB-T signal demodulation mode by the tuner (T) with frequency
double conversion.
The signal of the second IF by means of mixer (M) controlled by the local oscillator (LO) is converted into
the third IF, and further is filtered at 10.7 MHz frequency by the bandpass filter (BPF3), which defines the
receiver measurement filter bandwidth.
Logarithmic gain amplifier limiter (LGAL) performs logarithmation and signal detection.
Signal detector (SD) allows measuring of signal level by means of analog-to-digital converter (ADC). SD
uses peak detection for measuring analog channel level and average detection for measuring noise level
and digital channel power. The digital code of the input signal level logarithm is defined as real value and is
corrected in accordance with the calibration matrix of the control unit (CU) microcontroller.
In DVB-T signal demodulation mode the signal with the second IF, after bandpass filter (BPF1) filtering
comes to DVB-T demodulator (Dm), which performs demodulation and signal parameters measurement. The
control unit processes the measured results.
The control unit receives the commands from the user entered via keypad (K), processes the data,
displays them on the LCD, and also controls the operation with external PC.
The nonvolatile memory (NVRAM) stores the calibration coefficients set by the manufacturer, data log
pages, channel template, channel plans and service information.
The Power Unit (PU) generates the required voltages either from battery or from an external power
source.
2.5.3 Component arrangement
The IT-14 is implemented in plastic shockproof sectional housing that includes printed and threedimensional wiring. IT-14 dimensions are 193x94x53 mm.
The front panel of the Analyzer represents the tactile silicon keypad and a graphical display (Figure 1.1).
The front panel has a connector for PC connection and external power source connector (Figure 1.2). The
input 75-Ohm input “F”-male connector is located on the rear panel.
3 PREPARATION FOR OPERATION
Perform external examination to make sure your IT-14 is free from any visible mechanical damage.
Upon receipt of the package, check the availability of the items contained in it against the list provided
(Section 2.3).
If the IT-14 has been kept in the environment other than the rated operating conditions, leave your
Analyzer in facilities with normal operating conditions at least for 2 hours prior to operation.
4 OPERATION PROCEDURE
4.1 Controls and indicators
The location of controls, indicators and connectors is shown in Figure 1.1. These elements have the
following functions:
a) F1, F2, F3 functional keys enable the commands corresponding to icons shown on the screen of IT-
14;
b)
key allows you to return to the previous menu level;
c)
key enables auxiliary functions;
d)
, , ◄ , and ► arrows allow you to edit the current operation mode;
e)
key allows you to choose an element from the list;
f)
key switches the power of IT-14 on/off;
g)
12V DC 1.2A connector is for connection to an external power source;
h) USB
connector is for connection to a computer;
i) «INPUT» connector is for signal input, “F”-male connector.
4.2 Preparation for measurement
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Before you start operating your IT-14 make sure to carefully read this Operating Manual as well as to
inspect the location of the controls and indicators of the Analyzer (Section 4.1).
To prepare your Analyzer for operation with the external power source, connect the Charger to the
connector located on the front panel of the IT-14 and then to the power source.
To prepare your IT-14 for operation in stand-alone mode, powered by the battery, push and hold the
key until the LCD backlight turns on.
The following message (see Figure 4.2.1) will appear on the screen:
Figure 4.2.1
The screen displays the name and model of the Analyzer. After approximately 1 second, the Analyzer
will open the main mode-selection menu (Figure 4.3.1), further referred to as “Main menu”.
4.3 Measurement procedure
4.3.1 General information
The Analyzer features on-screen menu for selection of modes of operation. The icons of the menu
correspond to various functions. The Main menu (see Figure 4.3.1) will appear on the screen after the
Analyzer is powered up.
Figure 4.3.1 Figure 4.3.2
To change Main menu line press
or arrow. You will see the following line of the Main menu (Figure
4.3.2). To return back to the previous line press
or arrow once again. Function of menu are selectable
with the functional keys F1, F2 and F3, which are under the required icons. To return to the Main menu from
the selected function, press
key.
The Main menu contains 6 icons corresponding to the following functions:
a) LEVEL measurement ..........................................................................
;
b) SCAN measurement............................................................................
;
c) MER/BER measurement .....................................................................
;
d) Service menu.......................................................................................
;
e) Data manager menu............................................................................
;
f) PC connection .....................................................................................
.
When choosen
from theMain menu, Service menu will appear on the screen (Figure 4.3.3), and
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