WIRELESS MEASUREMENT INSTRUMENT GMT TRANSMITTER USER’S MANUAL Manual Part No. MNGMT20 Rev.
TABLE OF CONTENTS 1. INTRODUCTION 1.1 About This Manual... 1.2 About the Measurement System Product 2. PREPARATION FOR USE sass 241 2.1 Introduction 2.2 Precautions 2.2.1 Shock Hazard. 2.2.2 Static Sensitive Component 2.3 Unpacking and Inspecting... 2.3.1 Parts List 3. INTERFACE DESCRIPTION... 3.1 Introduction... 3.2 Front Panel 3.2 Figure-1 Front Panel. 3.3 Side Panel Features... 3.3 Figure-1 Side Panel 3.4 Keypad Operation 3.4.1 Mode Keys... 3.4.2 Numeric Keypad 3.4.3 Function Keys 3.5 Status LESS. 3.
. INSTALLATION AND OPERATION transferring sans sass ns renaissance screens del 4.1 Introduction 4.2 Installation Procedure... 4.3 Operation 4.3.1 Power Source. 4.3.2 Battery Operation 4.3.3 Frequency Control 4.3.4 Amplitude Control 4.3.5 Modulation Control 4.3.6 Transmit control 4.3.7 Error Codes... 5. PERFORMANCE SPECIFICATIONS .. 5.1 Frequency Range 5.2 Output Power... 5.3 Output Power Level Accuracy... 5.4 Frequency Stability 5.5 Output Power Spurious/Harmonics. 5.
PREFACE Certification Gray son Electronics Company certifies that this product met its published specification at time of shipment from the factory. ‘Warranty GEC warrants to the original purchaser (hereinafter called “Buyer”) that Equipment manufactured by GEC shall be free, under normal use and service, from defects in material and workmanship for a period of twelve (12) months from the date of delivery to the Buyer (the Warranty Period), and shall conform to GE's specifications.
1.1 1.2 1. Introduction 1. Introduction About This Manual This manual provides an overview of the GMT PCS Transmitter. The transmitter is the propagation test configuration partner for the Spectrum Tracker ™ wireless measurement instrument. Also included in this manual are procedures for unpacking, inspecting, and setting up the product for operation. About the Measurement System Product 1.2.
2. Preparation for Use 2. Preparation For Use 2.1 Introduction This section outlines precautions and preparations necessary before use of the measurement system. Also covered is unpacking and inspecting of the individual pieces and the requirements placed on the external power supply. 2.2 Precautions 2.2.1 Shock Hazard When replacing the AC fuse on the side panel, be sure to unplug the line cord and replace with a fuse of the correct rating and type.
2. Preparation for Use 2.3.
3. Interface Description 3. Interface Description 3.1 Introduction This section covers the front panel features and external interface ports. the first section gives a pictorial view of the front panel and a detailed description of the keypad and resultant indicators. The second part gives a detailed description of the side panel connectors and fuse holder. 3.
3. Interface Description 3.3 Side Panel Features 3.3 Figure-1 Side Panel 3.4 Keypad Operation 3.41 Mode Keys = Frequency Mode Modulation Mode Amplitude Mode Transmit Mode pz uo 3.4.2 Numeric Keypad 0-9 Numeric CE/C = Clear Entry ENT = Enter Key 3.4.
3. Interface Description 3.5 Status LESS Transmit LED ON when unit is transmitting Synthesizer LED ON when synthesizer is locked ALC lock LED ON when ALC loop is locked 3.6 Display LESS Frequency Indicates transmit frequency in MHz Modulation Indicates toggle function “OFF” or “EXTERNAL” Amplitude Indicates output power in 1 db increments Diagnostic Alternately displays internal DC voltage and internal operating temperature in degrees C. ’ 3.
4. Installation and Operation 4. Installation and Operation 4.1 Introduction This section covers the installation, set up and operational features of the GMT transmitter, 4.2 Installation Procedure Remove transmitter from shipping container and install in a location with an ambient temperature range between -20 and 55°C.
4, Installation and Operation 4.33 434 Frequency Control The keypad sequence is as follows: Push “F” button Enter desired frequency in 20 KHz steps EX 1850.020 Note that the initial “1” is reloaded. The “ENT” key is not required at the end of the frequency entry. Some 30 KHz frequency increments are available. The desired frequency must be dividable by 30:KHz exactly to be valid. Example: 1830.03 = 61,667.6 is not a valid channel .03 1920.
4. Installation and Operation 4.3.5 Modulation Control The keypad sequence is as follows: — Push “M” button — Modulation display will toggle between “EXT” and “OFF” with each “M” key closure. — “OFF” indicates a CW carrier — “EXT” indicates that the external I-Q Modulation input on the front panel DB-15 connector is now active. The “EXT” configuration should not be selected unless an external [-Q input is connected or the amplitude display will not be accurate.
4. Installation and Operation 4.3.7 Error Codes Error 10 Synthesizer has lost phase lock. Error 11 Power amplifier is not under leveling loop control. Error 14 PROMOTE data is invalid Error 15 Last state configuration data is invalid PA Temp Internal temperature above limit Low Bart Internal DC supply voltage below limit. — NOTE: Consult factory if error codes appear.
Performance Specifications 5. Performance Specifications Frequency Range 1850-1990 MHz, 20 or 30 KHz steps. Output Power 43 DBMS 3 dBm in 1 dB steps. Output Power Level Accuracy -20t00°C -125dB+0dB 010 +40° C dB +40 to +55° C -0dB +1.5dB Frequency Stability +-0.
5. Performance Specifications 5.7 Lead SWERVE Safe operation into Shortstop at all phase angles. 5.8 Output SWERVE 1.5:1 (14 dB Return Loss) 5.9 Modulation CW or externally supplied 1/Q source. Bandwidth 5 MHz 5.10 Power Consumption AC 115 volts (85 min, 264 max) 60 Hz (47 min, 63 max) 2.0 A nominal (2.25 A max) DC 12.0 volts (11 min, 13.8 max) 18 A nominal (20 A max) 5.11 Dimensions and Weight Height 11.0 inches Width 19.0 inches Depth 14.0 inches Weight 40 1b.
6. Brief Technical Description 6. Brief Technical Description 6.1 Introduction This section includes information on how the transmitter hardware functions. This information is presented so that the user may have a better understanding of how the unit works. NOTE: There are no field repairable assemblies in the transmitter, 6.2 Overview The GMT is a self contained 20 wart linear transmitter for Personal Communications Services (PCS) frequencies.
6. Brief Technical Description The synthesizer derives its frequency reference from an on board OTC. It can tune KHz steps as shown in the examples in section 4.3.3. Following the signal source modulator. It has a modulation bandwidth MHz. External 1/Q and DC Reference signals can be supplied to the modulator to produce any modulation format. Also the synthesizer/modulators output level is adjusted by the leveling control loop which is located in the filter-couplet.