UBS Axcera 325A 500-Watt VHF Low-band Television Transmitter User Manual Table of Contents
UBS-Axcera 500-Watt VHF Low-band Television Transmitter Table of Contents
Contents
Table of Contents
500-Watt VHF Low Band Transmitter Table of Contents
325A, Rev. 0 i August 1, 2002
TABLE OF CONTENTS
CHAPTER 1 INTRODUCTION
SECTION PAGE
1.1 Manual Overview ..................................................................................1-1
1.2 Assembly Designation Procedure ............................................................1-1
1.3 Safety .................................................................................................1-1
1.4 Maintenance.........................................................................................1-2
1.5 Material Return Procedure......................................................................1-2
1.6 Warranty for Axcera Products – Limited One-Year Warranty ......................1-3
CHAPTER 2 SYSTEM DESCRIPTION
2.1 System Overview..................................................................................2-1
2.2 Control and Status................................................................................2-2
2.2.1 VHF Exciter Tray..........................................................................2-3
2.2.2 VHF Amplifier Tray.......................................................................2-6
2.3 Input and Remote Connections...............................................................2-7
2.4 AC Input............................................................................................2-10
CHAPTER 3 CIRCUIT DESCRIPTIONS
3.1 Low-Band VHF Exciter ...........................................................................3-1
3.1.1 Aural IF Synthesizer Board, 4.5 MHz..............................................3-1
3.1.2 Sync Tip Clamp/Modulator Board...................................................3-2
3.1.3 Delay Equalizer Board ..................................................................3-5
3.1.4 IF Carrier Oven Oscillator Board ....................................................3-6
3.1.5 ALC Board, NTSC.........................................................................3-7
3.1.6 IF Phase Corrector Board............................................................3-13
3.1.7 VHF Mixer/Amplifier Enclosure Assembly ......................................3-15
3.1.8 Transmitter Control Board...........................................................3-16
3.1.9 Visual/Aural Metering Board........................................................3-21
3.1.10 Channel Oscillator Assembly, Dual Oven.....................................3-23
3.1.11 EEPROM FSK Identifier Board ....................................................3-23
3.1.12 IF Attenuator Board..................................................................3-24
3.2 VHF Low-Band Amplifier Trays..............................................................3-24
3.3 Bandpass Filter Assembly ....................................................................3-28
CHAPTER 4 INSTALLATION AND SETUP PROCEDURES
4.1 Site Considerations ...............................................................................4-1
4.2 Unpacking the Cabinets and Trays ..........................................................4-4
4.3 Installing the Cabinets and Trays............................................................4-5
4.4 Setup and Operation .............................................................................4-6
CHAPTER 5 DETAILED ALIGNMENT PROCEDURES
5.1 Low-Band VHF Exciter Tray with Baseband Video and Audio Inputs ............5-1
5.2 VHF Exciter Tray with 4.5-MHz Composite Input Kit..................................5-1
5.3 VHF Exciter Tray with Either Baseband or 4.5-MHz Composite Input...........5-2
5.4 IF Phase Corrector Adjustment...............................................................5-3
500-Watt VHF Low Band Transmitter Table of Contents
325A, Rev. 0 ii August 1, 2002
TABLE OF CONTENTS (continued)
SECTION PAGE
5.5 Linearity Corrector Adjustment...............................................................5-3
5.6 Phase and Gain Adjustment of the VHF Amplifier Trays .............................5-4
5.7 Calibration of the Forward Output Power Level of the Transmitter...............5-5
5.8 Calibration of the Reflected Output Level of the Transmitter.......................5-5
5.9 2-Way Combiner Assembly ....................................................................5-6
5.10 Bandpass Filter Assemblies ..................................................................5-6
5.11 Low-Band VHF Amplifier Tray ...............................................................5-6
5.11.1 AGC Control Board .....................................................................5-7
5.11.2 Phase Shifter Board....................................................................5-7
5.11.3 VHF Filter/Amplifier Board...........................................................5-7
5.11.4 Low-Band VHF Amplifier Board ....................................................5-7
5.11.5 Overdrive Protection Board .........................................................5-7
5.11.6 3-Way Splitter Board .................................................................5-7
5.11.7 Low-Band Amplifier Board...........................................................5-8
5.11.8 3-Way Combiner Board...............................................................5-8
5.11.9 Calibration of the Visual Plus Aural Output
Power and VSWR Cutback.........................................................5-8
5.12 Board Level Alignment Procedures ........................................................5-9
5.12.1 (Optional) 4.5-MHz Composite Input Kit .......................................5-9
5.12.2 Delay Equalizer Board.................................................................5-9
5.12.3 Composite 4.5-MHz Filter Board.................................................5-10
5.12.4 (Optional) 4.5-MHz Bandpass Filter Board...................................5-10
5.12.5 IF Carrier Oven Oscillator Board.................................................5-10
5.12.6 Sync Tip Clamp/Modulator Board ...............................................5-10
5.12.7 Aural IF Synthesizer Board, 4.5 MHz ..........................................5-13
5.12.8 ALC Board (Part 1 of 2).............................................................5-13
5.12.9 IF Phase Corrector Board ..........................................................5-14
5.12.10 ALC Board, NTSC (Part 2 of 2).................................................5-14
5.12.11 Channel Oscillator Board, Dual Oven ........................................5-15
5.12.12 x2 Multiplier Board .................................................................5-16
5.12.13 VHF Filter/Mixer Board............................................................5-16
5.12.14 Low-Band VHF Filter/Amplifier Board ........................................5-16
APPENDICES
APPENDIX A SYSTEM SPECIFICATIONS
APPENDIX B SAMPLE LOG REPORT SHEET
APPENDIX C BLOCK DIAGRAM/INTERCONNECT DRAWINGS
APPENDIX D SUBASSEMBLY DRAWINGS