Planar IT-14, Operating Manual

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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. IT-
14 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.