NEC DTU-70 Instruction Manual
  1. Manuals
  2. Brands
  3. NEC Manuals
  4. Transmitter
  5. DTU-70
  6. Instruction manual
NEC DTU-70 Instruction Manual

NEC DTU-70 Instruction Manual

18kw uhf digital tv transmitter
Hide thumbs
Table of Contents

Advertisement

Quick Links

Download this manual
HO2-345135-201
18kW UHF DIGITAL TV TRANSMITTER
DTU-70/13R9SQDx2
ＩＮＳＴＲＵＣＴＩＯＮ　ＭＡＮＵＡＬ VOL.Ⅰ
NEC Corporation
TOKYO,JAPAN

Advertisement

Table of Contents
loading

Related Manuals for NEC DTU-70

Summary of Contents for NEC DTU-70

  • Page 1 HO2-345135-201 18kW UHF DIGITAL TV TRANSMITTER DTU-70/13R9SQDx2 ＩＮＳＴＲＵＣＴＩＯＮ　ＭＡＮＵＡＬ VOL.Ⅰ NEC Corporation TOKYO,JAPAN...
  • Page 14 TV TRANSMITTER...
  • Page 15 GWP-G22996 INSTRUCTION MANUAL FOR DTU-70/13R9SQDx2 18kW UHF TV TRANSMITTER ..HO2-345135-201 VOL. I PRELIMINARY INFORMATIONS 1. Caution and Safety HO2-345135-201 - First Aid in the operation of this equipment HTD-E-3561 2. General Information HO2-345135-201 3. Functional Description HO2-345135-201 4. Operation and Adjustments HO2-345135-201 5.
  • Page 16 GWP-T22247W01 HO1-349495-202 TABLE OF ABBREVIATION ABBREVIA ABBREVIA NAME NAME -TION -TION Aural, Audio CCIR International Radio Consultitive Committee Alternating Current Conuter Clockwise Circuit Breaker CIB (D) Constant Impedance Band AD Converter Pass (Diplexer) Adjust CIN (D) Constant Impedance Automatic Gain Control Notch (Diplexer) Alarm Channel...
  • Page 17 GWP-T22247W01 ABBREVIA ABBREVIA NAME NAME -TION -TION Diode FB, F/B Feed Back D, DIG Digital Flat Cable DA Converter FIFO First Input First Output Direct Current Filament Directional Coupler Filter DEMO Demodulator Finite impulse Response Detector Frequency Modulation Deviation Final Power Amplifier Differential Gain FREQ Frequency...
  • Page 18 GWP-T22247W01 ABBREVIA ABBREVIA NAME NAME -TION -TION Relay NVRAM Nonvolatile Randam Access Memory Klystron OCXO Oven Controlled Crystal Coil Oscillator Light Emitting Diode Offset Linear Detector Over Load Linear Over Load Relay LO, LOC Local Output Power Low Pass Filter Operation Low Tension Output Filter...
  • Page 19 GWP-T22247W01 ABBREVIA ABBREVIA NAME NAME -TION -TION Transistor S. RFRM Snchronized Waveform Reformed Stereo Phonic Resistor Studio to Transmitter Link Randam Access Memory Switch Rubidium Synchronized Waveform Remote Control Gate REF, REFL Reflect SYNC Synchronize Reference SYNTHE Synthesizer REGEN Re-Generator Remote Transformer Response...
  • Page 20 GWP-T22247W01 ABBREVIA ABBREVIA NAME NAME -TION -TION Visual, Video Variable Capacitor VCXO Voltage Controlled Crystal Oscillator Video Distribution Amplifier Variable Frequency Oscillator Very High Frequency Variable Resistor Vestigial Single Side Band VSBF Vestigial Single Side Band Filter VSWR Voltage Standing Wave Ratio Wire Circulator...

  • Page 21: Table Of Contents

    GWP-G22996 INSTRUCTION MANUAL FOR DTU-70D Series UHF TV TRANSMITTER ..HO2-345135-201 CONTENTS SECTION. 1 CAUTION AND SAFETY General ........................1-1 Cautions for Use ..................... 1-1 SECTION. 2 GENERAL INFORMATION Scope ........................2-1 General ........................2-1 Coding System ......................2-3 Principal Characteristics ..................2-5 Composition ......................
  • Page 22 GWP-G22996 3-7-2 Signal Line ......................3-18 3-7-3 RF Monitor ......................3-18 3-7-4 Control Line ...................... 3-19 3-7-4-1 Parallel Interface ..................3-20 3-7-4-2 Serial Communication Interface .............. 3-25 3-7-5 System Control Interface .................. 3-31 3-7-6 Others ........................ 3-33 SECTION. 4 OPERATION AND ADJUSTMENTS General ........................
  • Page 23 GWP-G22996 SECTION. 5 MAINTENANCE General ........................5-1 How to Stop Operation ................... 5-2 Transmitter Operation Log ..................5-5 Monthly Maintenance Services ................5-5 Annual Maintenance Services ................5-6 5-5-1 Transmitter Station ................... 5-6 5-5-2 Transmitter ......................5-7 5-5-3 Check of Soldering....................5-8 5-5-4 Check Items for Exciter ..................
  • Page 24 GWP-G22996 SECTION. 6 WARRANTY AND REPAIR Warranty ......................... 6-1 6-1-1 Warranty ......................6-1 6-1-2 Corrective action ....................6-1 6-1-2-1 Hardware ....................6-1 6-1-2-2 Software ....................6-1 6-1-3 Conditions ......................6-2 6-1-4 No Defects Found ..................... 6-3 6-1-5 Exceptions of applications ................6-3 Repair and Supply of Units and Parts ..............

  • Page 25: Section. 1 Caution And Safety

    SECTION.1 CAUTION AND SAFETY...

  • Page 26: General

    GWP-G22996 DTU-70D Series UHF DIGITAL TV TRANSMITTER SECTION. 1 CAUTION AND SAFETY General This transmitter has a capacity capable of supplying energy up to 16.5kW at the maximum of single rack as the high-frequency output. Therefore, mishandling the transmitter may not only damage the equipment associated with the transmitter, but also cause injury or death of persons in access to live parts.
  • Page 27 GWP-G22996 (1) The cooling piping and combiner at the back of the UX5000QF PA and transmitter are maintained in high temperature. To prevent access to these parts which may cause injury, sufficient care should be taken. (1) The UX5000QF PA is a heavy weight. When lifting or transferring this equipment, two or more persons should work to prevent personal injury and shock to the equipment by its accidental fall.
  • Page 28 When you dispose of such products, please follow the agreements made by between you and NEC. The mark on the electrical and electronic products only applies to the current European Union Member States. Outside the European Union...

  • Page 37: Section. 2 General Information

    SECTION.2 GENERAL INFORMATION...

  • Page 38: Scope

    GWP-G22996 SECTION. 2 GENERAL INFORMATION Scope This instruction manual contains information on the operation and maintenance of the DTU-70D series UHF DIGITAL TV transmitter, including information on the separately installed equipments of the Water pump for cooling. Information for each units used in this transmitter should be referred to the each of unit instruction manuals.
  • Page 39 GWP-G22996 ○Coolant feeding is easier. ○Air purge is easier. ○Dusts that strainers or filters cannot remove will precipitate at the bottom of the tank and can easily be removed. Compact Size Its compact size (up to 5 PA mounted model, cooling system is built in transmitter rack）contributes to the effective use of the station building inside space.

  • Page 40: Coding System

    GWP-G22996 Coding System The coding system of the DTU-70/D is as follows. Digital TV Transmitters (UHF Band) : DTU-70/ : Output Power : 2.9kW : 4.3kW : 5.7kW : 7.1kW : 8.5kW : 9.9kW 11R2 : 11.2kW 12R6 : 12.6kW 13R9 : 13.9kW...
  • Page 41 Table 2-1 System Configuration of TV Transmitter S type P type W type TX TYPE Single Transmitter Single Transmitter with Redundancy Dual Transmitter in Parallel Operation (Single Exciter, Single Cooling) (Dual Exciter, Dual Cooling) OUTLINE TX-A DIAGRAM 9-Port U- Link Frame TX-B &...

  • Page 42: Principal Characteristics

    GWP-G22996 Principal Characteristics Table 2-2 RF output power : 2.9kW / 4.3kW / 5.7kW / 7.1kW / 8.5kW / 9.9kW / 11.2kW / 12.6kW / 13.9kW / 16.5kW Frequency range : UHF Band IV or V (470-862MHz) : ±2.5×10 Frequency stability over a period of 1 year with internal reference Power supply Voltage...

  • Page 43: Composition

    GWP-G22996 Composition It is recommended that operational personnel become familiar with the various components of the transmitter and their type names from both a functional and physical point of view. This will assist in the proper operation and maintenance of the transmitter. 2-5-1 Functional Composition Separate functions of the transmitter are grouped easily into the following four circuit...
  • Page 44 GWP-G22996 Table 2-3 Control and Cooling Exciter Power Amplifier Monitor Equipment Section Section Section Section S Type DTU-70/2R9SQ(F)D DTU-70/4R3SQ(F)D DTU-70/5R7SQ(F)D DTU-70/7R1SQ(F)D DTU-70/8R5SQD DTU-70/9R9SQD DTU-70/11R2SQD DTU-70/12R6SQD DTU-70/13R9SQD DTU-70/16R5SQD 2 - 7...
  • Page 45 GWP-G22996 Table 2-3 (continued) Control and Cooling Exciter Power Amplifier Monitor Equipment Section Section Section Section P Type DTU-70/2R9PQ(F)D DTU-70/4R3PQ(F)D DTU-70/5R7PQ(F)D DTU-70/7R1PQ(F)D DTU-70/8R5PQD DTU-70/9R9PQD DTU-70/11R2PQD DTU-70/12R6PQD DTU-70/13R9PQD DTU-70/16R5PQD 2 - 8...

  • Page 46: Physical Composition

    Physical Composition Outside view of typical DTU-70D series transmitter are shown in Fig.2-1 and Fig.2-2. The DTU-70 Transmitter up to 16.5kW is mounted in one rack which accommodates exciters, PAs, and control unit. Fig. 2-1 Front and rear view of the DTU-70D series transmitter (built-in cooling system)
  • Page 47 GWP-G22996 Fig. 2-2 Front and rear view of the DTU-70D series transmitter 2 - 10...

  • Page 48: Section. 3 Functional Description

    SECTION.3 FUNCTIONAL DESCRIPTION...
  • Page 49 GWP-G22996 SECTION. 3 FUNCTIONAL DESCRIPTION This section furnishes the operator with sufficient information pertaining to the functions of the DTU-70D series by reference to the circuit sections introduced in 2-5, as well as to the block diagram of Fig. 3-1. EXCITER POWER OUTPUT...

  • Page 50: Exciter Section

    GWP-G22996 Exciter Section DM-5000D ISDB-T Exciter is designed for digital TV transmitter system and which has most of essential functions of COFDM modulation, frequency up-conversion, linearity correction and etc. COFDM modulation function is complied with ISDB-T (ARIB STD- B31 and ABNT NBR 15601) 3-1-1 Characteristics Table 3-1 lists the electrical characteristics of Exciter.

  • Page 51: Power Amplifier Section

    GWP-G22996 Power Amplifier Section 3-2-1 UX5000QF Power Amplifier The UX5000QF PA is a Doherty, high power transistorized RF amplifier. The maximum output of this amplifier is 1560W average power, and the unit gain is approximately 77.9dB. The gain can continuously be varied by the input variable attenuator (LEVEL ADJ).

  • Page 52: Cooling Section

    GWP-G22996 Cooling Section This transmitter is cooled with coolant fed from pump rack. The coolant which flows into the transmitter is branched to cool the absorbed resistors for the power combiner and then cools the PAs and is discharged, combined again into one route, from the transmitter. For details, refer to the Instruction Manual of Pump Rack in section 6, and Heat Balance in 1, General, of Vol.

  • Page 53: Output Filter Section

    GWP-G22996 Output Filter Section This section consists of the harmonic filter and low pass filter (optional) for suppressing the spurious of the outputs of the power amplifier section. Also this harmonic filter consisted of λ/4 short circuit is used to protecting against lighting. Table 3-3 Attenuation characteristic of filters Attenuation[dB] ※...

  • Page 54: Control Section

    GWP-G22996 Control Section 3-5-1 General The transmitter is controlled mainly by the HPC-1605 TX Control. Two control modes, LOCAL and REMOTE, are provided. When the LOCAL mode is chosen, the transmitter is controlled on the operation panel mounted on the front panel of the transmitter, and does not accept external control.
  • Page 55 GWP-G22996 (1) ON CONTROL START No (REMOTE MODE) LOCAL “ LOCAL “ LED lights. “ LOCAL “ LED lights. LOCAL REMOTE TX ON TX ON ON CONT MEMORY EXTERNAL INTERLOCK “ INTERLOCK ” LED lights. RECYCLING HOLD PA PS ON COOLING ON COMMUNICATION WITH PA OK ?
  • Page 56 GWP-G22996 (2) OFF CONTROL START No (REMOTE MODE) LOCAL “ REMOTE ” LED lights “ LOCAL ” LED lights LOCAL REMOTE TX ON TX ON ON CONT MEMORY PA PS OFF “ TX ON ” LED goes off COOLING OFF DELAY 39sec Fig.
  • Page 57 GWP-G22996 (3) Control when a fault is encountered a) Faults A fault of a transmitter is classified into three (3) kinds as follows: 1) When this kind of fault is encountered, the operation of a transmitter is stopped coercively. And the transmitter must be protected absolutely from this kind of fault.
  • Page 58 GWP-G22996 Table 3-4 Faults from which the transmitter must be protected Component to be Item Fault Condition Control Item Protected 1. PA TEMP The temperature on the chassis of the Faulty unit : OFF PA exceeds setting temperature. 2. REFLECT The reflected power exceeds TX : OFF ...
  • Page 59 GWP-G22996 Table 3-5 Faults which, if encountered, will cause indication only Item Fault Condition Remarks 1. Exciter The output level of the exciter lowers by Another exciter is selected. 3dB. 2. PA The output level of PA lowers by 2dB. Even when the output level of the exciter is not normal, the PA will not be determined to...

  • Page 60: Operation Of Transmitter

    GWP-G22996 3-5-4 Operation of Transmitter The operation of transmitter is carried out with front panel of TX Control composed of an LCD display that displays condition of the transmitter and, a operation button. that carries out start/stop of the transmitter. Setting of the output frequency and clock time is made on this panel.
  • Page 61 GWP-G22996 «12» «14» <9> <11> «13» «15» <10> <12> Fig 3-6 Outside view of operation panel (P Type) 3 - 13...
  • Page 62 GWP-G22996 • Control Switch «1» MASTER CONTROL switch : When operation any control or select switch, Operate this switch simultaneously. «2» TX ON control switch : For TX ON control. «3» TX OFF control switch : For TX OFF control. «4»...
  • Page 63 GWP-G22996 • Indicator <1> TX ON : Transmitter is in ON status (Amber indication) <2> REMOTE : Indicates the Remote mode (Amber indication) <3> LOCAL : Indicates the Local mode. (Red indication) <4> POWER-A/B : Indicates the TX Control is power on. (Amber indication) <5>...

  • Page 64: Monitoring Section

    GWP-G22996 Monitoring Section This transmitter is provided with meters to allow output power check of the transmitter and parameters of each PA. The output power is detected by the detector circuit in the TX control unit and displayed by digital indication on LCD display. Further, monitor section incorporates an output power lower and higher detect circuit and in case the output power is not normal, an output power fault answer is sent to the TX control section.

  • Page 65: Interface

    GWP-G22996 Interface This subsection describes connection of the transmitter to external equipment. For the interface position and wiring routes, refer to the description in General of Vol. II, and mechanical drawings. 3-7-1 AC Line (See Table 3-6) Table 3-6 Connectors for AC Line Transferred Item Remarks...
  • Page 66 GWP-G22996 3-7-2 Signal Line In this transmitter connect various signal lines (ASI, 1PPS, 10MHz, etc.) to rear panel of exciter directly. The standard rear panel layout of exciter is shown in Fig. 3-8. The interface board is mounted on the rear side of the TX control. Fig.
  • Page 67 GWP-G22996 3-7-4 Control Line There are two types of interface for connection with external remote control, parallel (relay contact) type and serial communication type. Both types make interface with external control equipment through an interface board of TX control. The interface board is shown in Fig.
  • Page 68 GWP-G22996 3-7-4-1 Parallel Interface The connection of the parallel interface with remote control equipment is made using interface board connectors (J1 and J2). The control items are listed in Table 3-9 Table 3-9 Connectors for Remote control (Interface Board J1 to Remote control Equipment) Terminal No.
  • Page 69 GWP-G22996 Table 3-9 (continued) Terminal No. Item Description EXT. INTERLOCK 30/31 The output power of the transmitter can be applied to external equipment. TX LOCAL ANS 30/31 TX Local Mode TX REMOTE ANS 30/31 TX Remote Mode TX ON ANS 30/31 Means the TX ON condition.
  • Page 70 GWP-G22996 Table 3-10 Connectors for Remote control (Interface Board J2 to Remote control Equipment) Terminal No. Item Description 41/42 Means that the EX-A visual output power is EX-A V FAULT abnormal. 41/42 Means that the EX-B visual output power is EX-B V FAULT abnormal.
  • Page 71 GWP-G22996 Table 3-10 (continued) Terminal No. Item Description PA OUTPUT FAULT 41/42 The output power of some PAs is 2dB below the preset level. (APA OUTPUT 41/42 (Reserved) FAULT) PA REFLECT FAULT 41/42 The reflected power of some visual PAs is over.
  • Page 72 GWP-G22996 Table 3-10 (continued) Terminal No. Item Description WATER LEVEL LOW 41/42 Means that the quantity of coolant in the coolant tank on the pump rack decreased to a lower level than the set level. 41/42 Means that the coolant in the coolant tank WATER LEVEL on the pump rack was used up.
  • Page 73 GWP-G22996 3-7-4-2 Serial Communication Interface The connection of the serial communication interface with the remote control equipment is made by means of a connector of the interface board. The serial communication interface has a function to output data displayed on the LCD display.
  • Page 74 GWP-G22996 2) Setting of Rotary Switch & DIP Switch The Rotary switch (SW2) & DIP switch (SW3) on the control board in the TX control unit are set as follows. a) SW2 (Rotary switch) SW Position Baud Rate 1200bps 2400bps 4800bps 9600bps 19200bps...
  • Page 75 GWP-G22996 Positions of jumpers on the control board Positions of SW 2,3 on the control board Fig. 3-10 Parts layout of control board in TX control 3 - 27...
  • Page 76 GWP-G22996 (2) Serial Communication Connection (See Fig. 3-9, Rear side view of TX control) 1) RS-232C Table 3-11 REMOTE CONTROL (J3) on INTERFACE BOARD Pin No. Signal Receive Data (RXD) Transmit Data (TXD) Data Terminal Ready (DTR) Ground Data Set Ready (DSR) Request to Send (RTS) Clear to send (CTS) 2) RS-422...
  • Page 77 GWP-G22996 3) RS-485 Table 3-13 REMOTE CONTROL (J3) on INTERFACE BOARD Pin No. Signal Transmit Data + (TXD +) Transmit Data - (TXD -) Ground Receive Data + (RXD +) Receive Data - (RXD -) Table 3-14 REMOTE CONTROL (J4) on INTERFACE BOARD for daisy chain Pin No.
  • Page 78 GWP-G22996 (Connection for 4-wire) TX-D + TX-D + TX-D - TX-D - from previous next RX-D + RX-D + equipment equipment RX-D - RX-D - INTERFACE BOARD (Connection for 2-wire) TX-D + TX-D + /RX-D + /RX-D + TX-D - TX-D - /RX-D - /RX-D -...
  • Page 79 GWP-G22996 3-7-5 System Control Interface (See Table 3-15) The external interfaces of control items relating to the transmitter are connected through a Interface board. A connector (J5) of the Interface board accepts control commands from the system control and also sends out transmitter status necessary for the system control.
  • Page 80 GWP-G22996 Table 3-15 (continued) J5 (on the Interface Item Board) Description Terminal No. TX ON CONT 34/35 Means the reception of ON command MEMORY TX ON ANS 34/35 Means the TX ON condition. TX REMOTE ANS 34/35 TX Remote Mode Operation. PUMP ON ANS 34/35 Means the ON condition of PUMP.

This manual is also suitable for:

Dtu-70/2r9sqfdDtu-70/4r3sqfdDtu-70/5r7sqfdDtu-70/7r1sqfdDtu-70/8r5sqdDtu-70/9r9sqd ... Show all

Table of Contents