INSTRUCTION BOOK OPERATING INSTRUCTIONS WITH PARTS LIST MODEL 4450 THRULINE® WATTMETER
LIMITED WARRANTY All products manufactured by Seller are warranted to be free from defects in material and workmanship for a period of one (1) year, unless otherwise specified, from date of shipment and to conform to applicable specifications, drawings, blueprints and/or samples.
INSTRUCTION BOOK OPERATING INSTRUCTIONS WITH PARTS LIST MODEL 4450 THRULINE® WATTMETER © Copyright 1994 by Bird Electronic Corporation Instruction Book Part Number 920-4450-1 Rev.
Safety Precautions Safety Precautions The following are general safety precautions that are not necessarily related to any specific part or procedure and do not necessarily appear elsewhere in this publication. These precautions must be thoroughly understood and apply to all phases of operation and maintenance. KEEP AWAY FROM LIVE CIRCUITS Operating personnel must at all times observe general safety precautions.
MODEL 4450 THRULINE WATTMETER CAUTION STATEMENTS The following equipment cautions appear in the text and are repeated here for emphasis. CAUTION Do not drop the Thruline Wattmeter equipment or submit it to hard blows. The voltmeter circuitry or microammeter, even though it is shock mounted, may be damaged by severe impact.
About This Manual About This Manual This instruction book covers the model 4450 Thruline Wattmeter This instruction book is arranged so that essential information on safety is contained in the front of the book. Reading the Safety Precautions Section before operating the equipment is strongly advised. The remainder of this Instruction Book is divided into Chapters and Sections. Figures and tables are numbered sequentially within each chapter.
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Table of Contents Safety Precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Model 4450 Thruline Wattmeter Warning Statements . . . . . . . . . . . . . i Model 4450 Thruline Wattmeter Caution Statements . . . . . . . . . . . . . . ii About This Manual . . . . . . . . . . . . . . . . . . . . . . . . . . . iii Introduction Chapter 1 Purpose and function . . . . . . . . . . . . . . . . . . . . . . . . . . 1-1 Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
List of Figures Outline Drawing . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-2 Schematic Diagram . . . . . . . . . . . . . . . . . . . . . . . . . . . 1-3 Zero Adjustment Screw . . . . . . . . . . . . . . . . . . . . . . . . . . 4-1 VSWR Conversion Monograph. . . . . . . . . . . . . . . . . . . . . . .
Chapter 1 Introduction Purpose and function The Model 4450 Thruline Wattmeter is an insertion-type RF wattmeter designed to measure RF power flow and load match in 50 ohm RF coaxial transmission lines. Its primary intended use is for the test and evaluation of power line carrier equipment, although it is well suited low frequency low power RF application. When used in a 50 ohm application, with N type connectors, it has an insertion VSWR of less than 1.
Bird Model 4450 Thruline Wattmeter Specifications Impedance 50 ohms nominal Power range 5/25/100 Watts Insertion VSWR 1.10 maximum Connectors Bird QC type, Female N normally Supplied Temperature Range Operating Storage +5°C to +45°C (41°F to 113°F) -10°C to +45°C (14°F to 113°F) Accuracy* (From 5°C to 45°C) 30 to 535 kHz 20 kHz to 1 MH (Into a 50 ohm load) 5% of full scale 10% of full scale Dimensions 3"D x 353 64“W x 67 8”H (76 x 97.2 x 175mm) Insertion Loss 0.
- Schematic Diagram 1-3
Bird Model 4450 Thruline Wattmeter 1-4
Chapter 2 Theory Of Operation Traveling Wave Concept The operation of the Model 4450 Wattmeter is based on the traveling wave concept of RF transmission. As RF power is applied to a transmission line, there is a forward wave traveling from the transmitter to the load, and a reflected wave traveling from the load to the transmitter. The closer the load is matched to the line, the smaller the reflected wave will be.
Bird Model 4450 Thruline Wattmeter will be indicated on the microammeter as the power opposite to the forward power, or reflected power.
Chapter 3 Installation Portability The Model 4450 THRULINE Wattmeter is a portable unit and the housing is not designed for fixed mounting. A leather strap handle is provided on the unit for carrying purposes. When transporting the Model 4450 turn the range switch to the OFF position. This will shunt the meter movement and effectively dampen the pointer action to protect it during handling or shipping. CAUTION Do not drop the THRULINE Wattmeter equipment or submit it to hard blows.
Bird Model 4450 Thruline Wattmeter 3-2
Chapter 4 Operating Instructions The apparent features of the Thruline equipment have been discussed in the preceding sections. As previously mentioned, no batteries or external power source is required to operate the wattmeter. A sufficient amount of power is taken from the RF transmission line to operate the unit. This power is negligible and does not affect the power output to a noticeable degree.
Bird Model 4450 Thruline Wattmeter VSWR Calculations Figure 4-2 VSWR Conversion Monograph Power Values vs. VSWR 4-2 After obtaining the forward and reflected power readings described above, the VSWR may be found by calculation as described on page 2-1 Traveling wave vs. Standing wave. Conversion nomographs to simplify determining VSWR are provided below.
C h a p t e r 5 Maintenance General This chapter contains operator maintenance instructions, troubleshooting and parts information. With the relatively simple circuitry, construction, and self-contained nature of the Model 4450 Thruline equipment, only a moderate amount of maintenance is required. The major precaution for the safekeeping and maintenance of the wattmeter is handling; use reasonable care and do not drop the unit.
Bird Model 4450 Thruline Wattmeter Preventive Maintenance WARNING Provide adequate ventilation and observe normal precautions when using dry cleaning solvents. Many dry cleaning agents emit toxic fumes that may be harmful to your health if inhaled.
- Repair Although the Model 4450 is designed to be rugged and provide years of trouble-free service, occasional repair or replacement may become necessary. This section contains repair and replacement procedures. Repairs should not be attempted by the user for the first year warranty period as this may void the warranty. If a problem should occur in the line section or coupling circuits, the unit should be returned to the factory for repair and recalibration.
Bird Model 4450 Thruline Wattmeter Range and Mode Switch Replacement 5-4 5. Reinstall the meter and calibration board by reversing the disassembly procedure. Do not tighten the meter mounting screws excessively. 1. Remove back cover. 2. Peel off the rubber feet located in the back half of the bottom section to gain access to flat head screws securing the line section mounting bracket. 3. Remove the two screws. 4.
- Replacement Parts List Q T Y . D E S C R I P T I O N P A R T N U M B E R 1 Line section assembly 4450-003 1 Mounting bracket 450-020 2 PC board mounting brackets 4450-019 1 30 uA meter 2080-063 2 Switch knobs 4110-016 1 Meter housing 4450-009 1 Carrying strap 8580-003 8 Bumper feet 5-875 1 Back cover assembly 4450-005 2 “QC” connectors *See Below 1 PC board assembly (line section) 4450-015 1 PC board assembly (meter) 4450-014 2 RF choke (2.
QUALITY INSTRUMENTS FOR RF POWER MEASUEMENT From 2 to 2300 MHz and from 25 milliwatts to 250 kilowatts in 50 ohm coaxial line systems TERMALINE® ABSORPTION WATTMETERS LOAD RESISTORS CALORIMETERS THRULINE® DIRECTIONAL MONITORING WATTMETERS TENULINE® ATTENUATORS COAXWITCH® SELECTOR SWITCHES COAXIAL RF FILTERS SENTRILINE® FILTER-COUPLERS E L E C T R O N I C C O R P O R A T I O N 30303 Aurora Road, Cleveland, (Solon) Ohio 44139-2794
