INSTRUCTION BOOK OPERATING INSTRUCTIONS THRULINE® WATTMETER MODEL 4308 Electronic Corporation Cleveland (Solon) Ohio USA Copyright 2007 by Bird Electronic Corporation Instruction Book Part Number 920-4308 Revision D Thruline is a Registered Trademark of Bird Electronic Corporation
Bird Model 4308 Thruline Wattmeter
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. Keep Away From Live Circuits Operating personnel must at all times observe general safety precautions. Do not replace components or make adjustments inside equipment with the high voltage supply turned on. To avoid casualties, always disconnect power.
Bird Model 4308 Thruline Wattmeter Safety Symbols WARNING Warning notes call attention to a procedure which, if not correctly performed, could result in personal injury. CAUTION Caution notes call attention to a procedure which, if not correctly performed, could result in damage to the instrument. This symbol appears on the equipment indicating there is important information in the instruction manual regarding that particular area. + Note: Calls attention to supplemental information.
4308 Safety Statements USAGE ANY USE OF THIS INSTRUMENT IN A MANNER NOT SPECIFIED BY THE MANUFACTURER MAY IMPAIR THE INSTRUMENT’S SAFETY PROTECTION. USO EL USO DE ESTE INSTRUMENTO DE MANERA NO ESPECIFICADA POR EL FABRICANTE, PUEDE ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO. BENUTZUNG WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN.
Bird Model 4308 Thruline Wattmeter SERVICE SERVICING INSTRUCTIONS ARE FOR USE BY SERVICE -TRAINED PERSONNEL ONLY. TO AVOID DANGEROUS ELECTRIC SHOCK, DO NOT PERFORM ANY SERVICING UNLESS QUALIFIED TO DO SO. SERVICIO LAS INSTRUCCIONES DE SERVICIO SON PARA USO EXCLUSIVO DEL PERSONAL DE SERVICIO CAPACITADO. PARA EVITAR EL PELIGRO DE DESCARGAS ELÉCTRICAS, NO REALICE NINGÚN SERVICIO A MENOS QUE ESTÉ CAPACITADO PARA HACERIO. WARTUNG ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR FÜR GESCHULTES FACHPERSONAL.
OPPORTUNAMENTE ADDESTRATO. PER EVITARE PERICOLOSE SCOSSE ELETTRICHE NON EFFETTUARRE ALCUNA RIPARAZIONE A MENO CHE QUALIFICATI A FARLA. RF VOLTAGE MAY BE PRESENT IN RF ELEMENT SOCKET - KEEP ELEMENT IN SOCKET DURING OPERATION. DE LA TENSION H.F. PEAT ÊTRE PRÉSENTE DANS LA PRISE DE L’ÉLÉMENT H.F. - CONSERVER L’ÉLÉMENT DANS LA PRISE LORS DE L’EMPLOI. HF-SPANNUNG KANN IN DER HF-ELEMENTBUCHSE ANSTEHEN - ELEMENT WÄHREND DES BETRIEBS EINGESTÖPSELT LASSEN.
Bird Model 4308 Thruline Wattmeter LE
About This Manual This instruction book covers the model 4308 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. At the beginning of each chapter a general overview will be given, describing the contents of that chapter.
Bird Model 4308 Thruline Wattmeter LEEE
Table Of Contents Safety Precautions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . i Warning Statement. . . . . . . . . . . . . . . . . . . . . . . ii Caution Statement. ii . . . . . . . . . . . . . . . . . . . . . . 4308 Safety Statements. . . . . . . . . . . . . . . . . . . . iii About This Manual. . . . . . . . . . . . . . . . . . . . . . . vii Introduction. . . . . . . . . . . . . . . . . . . . . . . . . . . 1 Purpose and Function. . . . . . . . . . . . . . . . . . . . .
Bird Model 4308 Thruline Wattmeter Operating Instructions. . . . . . . . . . . . . . . . . . . . . 9 Zero Adjust. . . . . . . . . . . . . . . . . . . . . . . . . . . 9 Range Switch and Power Measurement. . . . . . . . . . . . 9 VSWR Calculations. . . . . . . . . . . . . . . . . . . . . . . 10 Maintenance. . . . . . . . . . . . . . . . . . . . . . . . . . 13 Troubleshooting. . . . . . . . . . . . . . . . . . . . . . . . . 13 Cleaning. . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Chapter 1 Introduction This chapter contains introductory information including product specifications, items supplied, and accessory items. Purpose and Function The Model 4308 Thruline Wattmeter is a portable multi-range RF wattmeter. It is a device which requires no external power source or batteries for operation. It is used to measure RF power when inserted into a transmission line of 50 ohms impedance.
Bird Model 4308 Thruline Wattmeter Specifications Impedance: Full Scale Power Range: Insertion VSWR: Female “TNC” Connector 50 ohms nominal 1.5, 5, 15, 50 Watts 1.05 max. from 440-512 MHz 1.07 max. from 512 to 960 MHz Female “UHF” Connector 1.08 max. from 440-512 MHz 1.12 max. from 512 to 960 MHz 0.1 dB max. 440 to 512 MHz 0.13 dB 512 to 960 MHz Insertion Loss: With Female “UHF” Connectors Accuracy: Weight, Nominal: Dimensions, Nominal: Without Connectors: 0.1 dB 440-512 MHz 0.
Chapter 2 Theory Of Operation Travelling Wave Viewpoint The operation of the Model 4308 wattmeter is based on the travelling wave concept of RF transmission. As RF power is applied to a transmission line, there is a forward wave travelling from the transmitter to the load and a reflected wave travelling from the load back to the transmitter. The closer the line termination, or load, is matched to the line impedance, the smaller the reflected wave will be.
Bird Model 4308 Thruline Wattmeter Figure 1 Model 4308 Outline Drawing RUBBER FEET (4) Q.C. CONNECTOR 6-7/8 1.
Theory Of Operation Power Since there is a definite relationship between the standing wave ratio and the forwardreflected power ratio, the forward and reflected powers may be read from the Thruline Wattmeter and converted to VSWR. The charts are furnished in this Instruction Book. Coupling Circuit The coupling circuit which samples the travelling waves is in the Plug-In Element.
Bird Model 4308 Thruline Wattmeter currents will flow according to the direction of the travelling waves producing them, whereas the capacitive portion of these currents is independent of the direction. Therefore, in either position of the Plug-In Element, the coupling currents produced from the waves of one direction will add in phase, and those produced from waves of the opposite direction will accordingly subtract in phase. The additive direction is indicated by the arrow.
Chapter 3 Installation Portability 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. The Model 4308 is a portable instrument, and the housing is not designed for fixed mounting. A strap is provided for carrying purposes. To protect the meter movement during periods of transit, put the range switch in the “TRANSIT” position.
Bird Model 4308 Thruline Wattmeter 2. Rotate the element so that the arrow points in the direction of power flow. If coaxial cables other than 50 ohm impedance are used, a mismatch will occur which may cause serious inaccuracies in the readings.
Operating Instructions Chapter 4 Operating Instructions A description of the features of the Thruline Wattmeter have been discussed in the previous sections. Read and become familiar with the following instructions before operating the Model 4308. As mentioned, no batteries or external power sources are required to operate the meter. A small but sufficient amount of power is obtained from the transmission line into which the unit is connected.
Bird Model 4308 Thruline Wattmeter The Model 4308 is supplied with a special broadband 50 W element with a frequency range of 440-960 MHz. This element is capable of operating at lower power levels and up to 50 watts equally as well. At lower power levels, the range switch should be turned to a lower setting for better resolution. Do not select a range lower than necessary or damage to the meter may result. Forward power (i.e.
Figure 5 VSWR Conversion Nomograph 20 18 16 14 VSWR= 12 Reflected Power 1+ Forward Power 1 10 Reflected Power Forward Power 6 VS WR 10 4 2. 5 3. 0 4. 0 2. 0 2.0 1.8 1.6 1.4 1. 5 1. 6 1. 8 1.2 1. 4 1. 3 1.0 1. 25 .6 1. 05 1. 06 .4 1. 1 1. 0 0 1. 9 08 1. 07 1. 20 .8 1. 16 1. 14 1. 12 REFLECTED POWER - WATTS 8 .2 0.5 1.0 1.5 2.0 2.5 3.0 4.0 5.
Bird Model 4308 Thruline Wattmeter 10 1.0 .9 .8 .7 VS WR Figure 6 VSWR Conversion Nomograph .6 3. 0 4. 0 .5 2. 5 2. 0 1. 8 .3 1. 5 1. 6 .2 1. 20 1. 25 1. 3 1. 4 .1 .09 .08 .07 1. 1 1. 0 09 1. 08 1. 07 1. 12 1. 16 1. 14 .06 1. 06 .05 .04 1. 04 1. 05 REFLECTED POWER - WATTS .4 1. 03 .03 .02 .01 0.5 1.0 1.5 2.0 2.5 3.0 4.0 5.
Chapter 5 Maintenance This chapter includes cleaning, inspection, troubleshooting, and performance information. Troubleshooting Use the following table to aid in isolating problems, their possible cause, and corrections. Cleaning Problem Possible Cause Correction No meter indication No RF power applied to unit. Check RF source and check cables. Reposition element “Arrow” on Plug-In Element pointed in the wrong direction. No pick-up from dc contact finger Open or short circuit in dc circuit.
Bird Model 4308 Thruline Wattmeter Problem Intermittent or Inconsistent Meter Readings High VSWR or Reflected power Possible Cause Faulty transmission line or antenna Sticky or defective meter Dirty dc contact on element Bad load or poor connectors Shorted or open transmission line Correction Inspect line Replace or return wattmeter to the factory for meter replacement and calibration Clean contact Replace load, antenna or connectors.
Maintenance Line Section or Element Coupling Circuit If a problem should occur in the line section or element coupling circuit, it is advised that the unit be returned to Bird Electronic Corporation for repair and recalibration. Meter Housing For access to the inside of the meter housing, the back cover must be taken off. To do this: 1. Remove the four screws located near the back at the top and bottom of the sides. 2. Pull the cover straight off. Line Section and Circuit Board 1.
Bird Model 4308 Thruline Wattmeter These parts are not subject to further disassembly and must be replaced in their entirety if defective. The circuit board is only replaceable at the factory. 6. Reassemble the unit by reversing the above procedures. Connector Replacement The Model 4308 is normally supplied with two Female TNC Bird Quick-Change Connectors. Other “QC” connectors are available. These connectors may be obtained from Bird Electronic Corporation. Refer to the Available Connector List.
Maintenance Meter Replacement To replace the meter in the unit follow these steps: 1. Disconnect the meter leads from the terminals on the back of the meter. 2. Remove the screws securing the meter in place. The screws are located on each side of the housing. 3. Pull the meter, with the shock mount assembly, straight out of the unit. 4. Reinstall the meter, be sure the bumper feet, shock mount strip, and shock mount ring are in place on the meter. 5.
Bird Model 4308 Thruline Wattmeter I Make all connections as short as possible to avoid mismatches and additional insertion losses. I Make all calibration checks on each range at the upper one-third of the scales. I If the unit is found to be outside the stated accuracy, the unit must be returned to the factory for recalibration. Customer Service Any maintenance or service procedure beyond scope of those provided in this section should be referred to a qualified service center.
Sales / Repair Facilities U.S.A. Sales and Manufacturing Bird Electronic Corporation 30303 Aurora Road Cleveland (Solon), Ohio 44139-2794 Phone: (440) 248-1200 Fax: (440) 248-5426 Sales Facilities European Sales Office Bird Electronic Corporation Berkhamsted House 121 High Street Berhamsted Hertfordshire HP4 2DJ England Phone: 44 1 442 870097 Fax: 44 1 442 870148 Pan Asian Sales Office Bird Electronic Ltd.
Bird Model 4308 Thruline Wattmeter Replacement Parts List Item Qty.
Maintenance Connector *Available “QC” Type Connectors Part Number Connector Part Number N-Female N-Male HN-Female HN-Male LC-Female LC-Male BNC-Female BNC-Male SMA-Female SMA-Male 7/8" EIA 4240-062 4240-063 4240-268 4240-278 4240-031 4240-025 4240-125 4240-132 4240-336 4240-334 4240-002 1-5/8" EIA Fixed 7/16" IEC (Jack) Type 169-4 4240-096 4240-344 LT-Female LT-Male C-Female C-Male UHF-Female UHF-Male TNC-Female TNC-Male SC-Female Mini UHF-Female 7/16" IEC (Plug) Type 169-4 1-5/8" EIA Swivel Open Ter
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.
QUALITY INSTRUMENTS FOR RF POWER MEASUREMENTS From 2 to 4000 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 ELECTRONIC CORPORATION 30303 Aurora Road Cleveland, (Solon) Ohio 44139-2794
