Bird Brain Bird 4391A User's Manual
Contents
1. C Ll N S N S N S Parts List This section contains an illustrated list of all authorized replacement parts for the 4391A RF power Analyst Parts are grouped into major assemblies and subassemblies E e e N AO a e gl H Daw 5 a e 68 rl E 2 IND E a 5 55 2 58 a Description Part No Connector QC F N 4240 062 LED display DS1 054 5 1337 Keyboard legend 4386 012 PC board Main assembly 4391B007 Velcro strap 5 1958 PC board assy includes rectifier circuit 4391A041 Fuse Slo Blo IEC 1 8 amp 5A2257 7 Battery rechargeable C cell 5A1230 Dust plug 3610 031 Cable power cord 115V 230V 4421 055 N S not shown in figure 30 Qty FN GO Hopi BP b Maintenance Figure 25 Line Section gt Assembly y S N 1723 FI 2 and below A All I 3 10 11 8 5 J Y 4 L 6 SN 7 Item No Description Part No Figure 25 1 Line Section Subassembly 4381 005 2 PC Board Data Acguisition Assy 43914006 3 Bead Keying 4391 026 4 Spacer 4391 027 5 Screw Machine filister head COML No 4 40 1 4 in lg sst 6 Support 4381 029 7 Screw Machine filister head COML No 8 322. CES DISPOSITIFS SONT QUIP S DE BATTERIES RECHARGEABLES SEUL LE PERSONNEL D ENTRETIEN AUTORIS EST HABILIT LES REMPLACER LE UNIT SONO DOTATE DI BATTERIE RICARICABILI CHE DEVONO DA COME SPECIFICATO DAL PRODUTTORE LA PROTEZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA USE CORRECT VOLTAGE SETTING AND FUSE SEE MANUAL UTILISER UNE TENSION ET UN FUSIBLE CORRECTS CONSULTER LE MODE D EMPLOI USE LA INSTALACION Y FUSIBLE DE VOLTAJE CORRECTO VEA EL MANUAL AUSSCHLIESSLICH VORSCHRIFTSM SSIGE WECHSELSPANNUNGS EINSTELLUNG UND SICHERUNG BENUTZEN SIEHE DAZU HANDBUCH UTILLIZZARE TENSIONE E FUSIBLE ADATTI FARE RIFERIMENTO AL MANUALE BE SURE THE 115 230V AC VOLTAGE SELECTOR IS SET TO THE PROPER LINE VOLTAGE AND THE CORRECT AC LINE FUSE IS INSTALLED BEFORE AC POWER IS APPLIED S ASSURER QUE LE S LECTEUR DE TENSION 115 230V C A EST BIEN R GL POUR LA TENSION DU R SEAU ET QUE LE FUSIBLE DE LIGNE CORRECT EST EN PLACE AVANT DE METTRE SOUS TENSION C A CERCIORESE QUE EL SELECTOR DE VOLTAJE DE 115 230V CA ESTE COLOCADO A LA LINEA DE VOLTAJE APROPIADA Y QUE EL FUSIBLE ESTE INSTALADO A LA LINEA CA ANTES DE APLICAR LA CORRIENTE ALTERNA VOR EINSCHALTEN DER WECHSELSTROMZUFUHR SICHERSTELLEN DASS DER 115 230V WECHSELSPANNUNGS SELEKTOR AUF DIE VORSCHRIFTSMASSIGE LEITUNGSSPANNUNG EINGESTELLT UND DIE RICHTIGE WECHSELSTROM HAUPTSICHERUNG EINGESETZT IST Bird Model 4391M Power Analyst PRIMA DI EROGARE CO
3. When not in use store the RF Power Analyst with the LINE OFF BATT switch is in the off position 3 Charge the batteries for 16 hours prior to extended use of the RF Power Analyst Refer to Battery Care on page 18 Perform a periodic inspection to ensure that the RF power analyst is always operational Any damage noticed during inspection should be listed and repaired before use 1 Visually inspect the equipment for loose or damaged parts 2 Wipe dust and dirt from the front panel and lower hous ing Remove stubborn dirt with mild detergent and a soft cloth WARNING Use dry cleaning solvents in a well ventilated area Avoid excessive inhalation of solvent fumes since they can be toxic in heavy concentrations Always wear eye protection and avoid skin contact with the solvent 3 Clean the inside of the line section bores using cotton swab stick dampened with alcohol 4 Visually inspect the RF connectors for any sign of wear or damage and replace if necessary Clean the connec tors with alcohol or any acceptable dry cleaning fluid Do not store the instrument for long periods of time without recharging the batteries When the instrument is stored for long periods of time without use the batteries will loose their charge and also loose the ability to reach full charge when put into service To restore the battery charge perform a full charge for 16 hours If the batteries are not fully charged after 16 hours comp
4. Aid Figure 14 Peaking Aid A Operating Instructions The peaking aid is useful for making adjustments to optimize any of the parameters which the Model 4391A measures After the mode is selected press the delta key momentarily This blanks the least significant digit of the display and replaces it with a right facing arrow head if the measured quantity is increasing or a left facing arrow head if it is decreasing If there is no change the digit is left blank To find a peak begin making the adjustment in whichever direction produces a right facing arrow and continue slowly in that direction until the arrow head turns around At this point the peak has been reached To check to make sure the peak has not been passed press the MAX key to read the highest value read and release it to read the current value The two should be the same Desired minimum levels e g of reflected power or of SWR are found in a similar manner 17 Bird Model 4391A Power Analyst Battery Care 18 With average use the nickel metal hydride batteries in the 4391A will power the unit for 12 hours before needing recharged The 4391A will maintain rated accuracy until all the decimal points light indicating that recharging is required To recharge connect AC power to the unit To fully charge the batteries requires approximately 16 hours To prolong the life of the batteries it is recommended that you periodically allow the batteries to disc
5. and those produced from waves of the opposite direction will accordingly subtract in phase The additive or arrow direction is assigned to the forward wave Theory of Operation The electrical values of the element circuits are carefully balanced and designed so that current from the reverse wave will cancel the other almost completely The result is directivity always higher than 25 dB which means that the element is highly insensitive nulled to the REVERSE direction wave Being highly directional the Thruline element is sensitive at one setting only to one of the travelling waves that produce standing waves by interference Thruline Wattmeter measurements are therefore independent of position along standing waves Figure 4 Readings with Various Envelopes Heating Power o S 2 lt PEV PEV V2 PEVrms arbitrary Frequency Spectrum C Carrier chosen at 100 volts in all examples PEV Peak Envelope Voltage Carrier or suppressed carrier PEV was arbitrarily Transmission Type and Scope Pattern 50 ohms Zo Bird Model 4391A Power Analyst Operating on AC Power Figure 5 Rear Panel Chapter 3 Installation Model 4391A RF Power Analyst is completely portable and very suitable for field or laboratory use Its power is derived from rechargeable nickel metal hydride batteries inside the unit or from an AC outlet via the power cord supplied with
6. as follows voltages are corrected for error due to dc drift in the analog circuitry Each voltage is converted to square root of power using stored data tables These values are then combined mathematically to arrive at the final result in binary This 16 used to update the registers containing the last value the maximum value or the minimum value as required Finally the result is converted to a decimal number and placed into a register from which the display driving routine operates Figure 3 RF Coaxial Line Plug In Element Schematic Diagram XMIR losco Jj LOAD or Crystal LOAD Diode Directional Coupling Detector DC Element DC Contact The coupling circuit that samples the travelling waves is in the Plug in Element The circuitry of the element and its relationship to the other components of the Thruline Watt meter are illustrated in the schematic diagram Energy will be produced in the coupling circuit of the element by both mutual inductance and capacitance from the travelling RF waves of the line section The inductive currents will flow according to the direction of the travelling waves producing them The capacitive portion of these currents is independent of the direction of the travelling waves Therefore assuming that the Plug in Element remains stationary the coupling currents produced from the waves of one direction will add in phase
7. is placed in the socket marked REFLECTED and is normally pointed in the direction opposite to forward power flow The elements are clamped in place by the hold down catches on the face of the line section These catches must be used to avoid error due to the element not contacting the bottom or seating plate of the socket With the element s in place set the range switches to correspond Installation with the nominal power range of the elements For example if the forward element is a 5 watt element the switches are set at 5 and x1 For a 250 watt element they are set at 2 5 and x100 Sometimes it is necessary to use milliwatts or kilowatts as the unit of measure In other words 1 watt becomes 10 x 100 milliwatts and 2500 watts becomes 2 5 x 1 kilowatts Bird Model 4391A Power Analyst 10 Operating Modes Reading Forward CW Power Figure 6 Forward Power CW Chapter 4 Operating Instructions Model 4391A has nine modes of operation which are selected by pressing the mode keys momentarily In addition each mode has three output options selected by pressing the modifier keys Detailed descriptions of the modes and output options follow For this measurement only a forward element is needed Install the meter and element according to the preceding paragraphs and move the power switch to LINE or BAT depending on the power source desired When powered up the Model 4391A always goes into the forward CW power
8. the device The batteries are shipped in a low charge state It is therefore recommended that you charge the instrument for 16 hours before using it for continuous operation CAUTION Long term storage of this instrument can affect battery performance and reduce battery life Do not store the instrument for long periods of time without recharging the batteries refer to page 19 Failure to comply may result in reduced battery charge and shortened battery life For ac power operation the Model 4391A is simply connected to an AC receptacle using the line cord provided The correct AC voltage is selected via a rear panel switch Figure 5 The meter may be operated this manner with the batteries removed if desired CAUTION Always be certain the 115 230 voltage selector is set to the proper voltage before ac power is applied MODEL 4391A PATENT 4 263 653 DELAY FUSE SS 1 8 AMP 250 VAC S A 2 A 4 2 Description 1 AC input voltage selector switch 2 Fuse holder 3 AC power cable connector Bird Model 4391A Power Analyst Connections Table 1 Plug In Elements Required The Model 4391A contains a short section of rigid 50 ohm coaxial air dielectric transmission line To make measurements relating to the travelling waves in a coaxial line that line must be discon
9. the housing item 3 Figure 18 Removing Front Panel Main Printed Circuit PC Board Removal 5 6 Maintenance Lift the front panel from the housing Be careful to clear the line section blocks Remove pads from the three toggle switches da gt REFLECTED RANGE 25 x10 Dou B alla INE OFF 2648 Remove the front panel Refer to Front Panel Removal on page 24 Disconnect cable assembly at header P1 Figure 19 page 26 item 1 Remove the six screws and washers that secure the cir cuit board supports to the housing item 2 CAUTION Internal batteries are connected Remove one of the battery tubes before unsoldering wires connected to the Main PCB Failure to comply may result in permanent equipment damage and severe shock to individuals Lift the Main PC board and remove one battery tube Refer to figure on page 29 On the Main PC board unsolder and remove the red and orange wires that come from the power supply circuit board 25 Bird Model 4391A Power Analyst Figure 19 Removing Main PCB QC 1 Remove the eight screws four on each connector that Connectors secure the connectors t
10. watts milliwatts or kilowatts in 9 ranges from 2 5 to 1000 full scale forward power and 0 25 to 100 full scale reflected power depending on the Plug in Element In addition it reads SWR directly over the range of 1 00 to 99 99 percent modulation directly over the range of 0 0 to 99 9 and return loss over the range of 0 to 36 1 dB For convenience forward and reflected CW power can be displayed in dBm dB above 1 milliwatt from 6 dB above to 24 dB below nominal element range Power range and frequency band are determined by the Plug in Elements used Two switches on the front panel of the instrument are set by the user to correspond to the nominal power range of the forward element The reflected element is assumed to have a nominal range one tenth that of the forward element In any mode of operation the instrument can recall from memory the lowest or highest reading taken or tell the operator whether the newest reading 1s less than equal to or greater than the previous reading Bird Model 4391A Power Analyst Description Figure 1 Outline Drawing The instrument 16 housed in an aluminum case approximately 4 3 8 inches high by 9 5 8 inches deep by 6 1 4 inches wide 111 mm x 244 mm x 159 mm including connections see Figure 1 At each end of the line section are Bird Quick Change type RF connectors which may be easily interchanged with any other Bird QC connector See Bird Catalog for types available Operating power is de
11. 1 2 in lg sst 8 Screw Machine filister head COML No 4 40 7 8 in lg sst 9 Spacer 4391 035 1 10 Cover PC Board 4391 034 11 Lock Washer No 4 internal sst COML N A Line Section Complete 4391 014 Qty NNN FR A N bh 31 Bird Model 4391A Power Analyst Figure 26 y Line Section N P Assembly S N 1724 1 7 and above Ey TU Pan i 3 w n 8 _ 8 y 5 6 es A Ta C Part No Description Part No Figure 26 1 Line Section Subassembly 4381 005 2 PC Board Data Acquisition Assy 4391A006 3 Bead Keying 4391 026 4 Spacer 4391 027 5 Screw Machine filister head COML No 4 40 1 4 in lg sst 6 Support 4381 029 7 Screw Machine filister head COML No 8 32 1 2 in lg sst 8 Hex Nut with nylon insert No 4 40 1131 1013 00 9 Spacer 4391 035 1 10 Cover PC Board 4391 034 11 Lock Washer No 4 internal sst COML 12 Standoff Threaded 4391 038 32 Qty N NNN FR b NN Maintenance Customer Service Any maintenance or service procedure beyond the scope of those in this chapter should be referred to a qualified service center If you need to return the unit for any reason contact the Bird Service Center for a return authorization instruments returned must be shipped prepaid and to the attention of Bird Service Center Bird Service Center 30303 Aurora Road Cleveland Solon Ohi
12. 5 1 30 1 35 1 40 Return Loss dB 46 1 40 1 36 6 34 2 32 3 30 7 29 4 28 3 27 3 26 4 281 20 8 191 17 7 16 5 15 6 Reflected Power 0 00 0 01 0 02 0 04 0 06 0 08 0 11 0 15 0 19 0 23 0 49 0 83 1 23 1 70 2 22 2 78 VSWR 1 45 1 50 1 75 2 00 2 25 2 50 2 75 3 00 3 25 3 50 3 75 4 00 4 25 4 50 4 75 5 00 Return Loss dB 14 7 14 0 11 3 9 50 8 30 7 40 6 60 6 00 5 50 5 10 4 70 4 40 4 20 8 90 8 70 8 50 Reflected Power 96 8 87 4 00 7 44 11 11 14 79 18 37 21 78 25 00 28 03 30 86 33 52 36 00 38 32 40 50 42 53 44 44 PEP power measurements are made in the same manner as CW power readings described above except that the FWD PEP and RFL PEP buttons are pressed and the readings are displayed directly as peak power IS NOTE The accuracy of measurements made with modulation having a frequency duty cycle pulse width or repetition rate outside the instrument range cannot be assured in any mode of operation 13 Bird Model 4391A Power Analyst Measuring Amplitude Modulation Table 3 Amplitude Modulation Figure 10 Amplitude Modulation 76 14 Only a forward element is required for this mode Point the element in the direction of forward power and press MOD Modulation is displayed directly in percent provided the average signal is above 10 and the PEP of the signal is below 40096 of the element s nominal full sca
13. INSTRUCTION BOOK OPERATING INSTRUCTIONS MULTI PURPOSE THRULINE WATTMETER RF POWER ANALYST MODEL 4391A DINO Electronic Corporation Cleveland Solon Ohio USA Copyright 2008 by Bird Electronic Corporation Instruction Book Part Number 920 4391A Rev H Thruline amp and Power Analyst are Registered Trademark of Bird Electronic Corporation 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 normal safety regulations Do not replace components or make adjustments inside the equipment with high voltage turned on To avoid casualties always remove power Shock Hazard Do not attempt to remove the RF transmission line while RF power 15 present Radiated RF power is a potential health hazard Observe general safety precautions for handling high voltage equipment Always disconnect power before attempting any repairs Do Not Service or Adjust Alone Under no circumstances should any person reach into an enclosure for the purpose of service or adjustment of equipment except in the presence of someone who 1s capable of rendering aid Chemical Hazard Dry cleaning solvents for cleaning parts may be potentiall
14. RRENTE ASSICURARSI CHE IL SELETTORE DI VOLTAGGIO 115 230 V C A SIA REGOLATO CORRETTAMENTE E CHE IL FUSIBLE ADATTO ALLA LINEA DI ALIMENTAZIONE C A SIA INSTALLATO RF VOLTAGE MAY BE PRESENT IN RF ELEMENT SOCKET KEEP ELEMENT IN SOCKET DURING OPERATION DE LA TENSION H F PEAT TRE PR SENTE DANS LA PRISE DE L L MENT H F CONSERVER L L MENT DANS LA PRISE LORS DE L EMPLOI HF SPANNUNG KANN IN DER HF ELEMENT BUCHSE ANSTEHEN ELEMENT WAHREND DES BETRIEBS EINGESTOPSELT LASSEN PUEDE HABER VOLTAJE RF EN EL ENCHUFE DEL ELEMENTO RF MANTENGA EL ELEMENTO EN EL ENCHUFE DURANTE LA OPERACION IL PORTAELEMENTO RF PU PRESENTARE VOLTAGGIO RF TENERE L ELEMENTO NELLA PRESA DURANTE IL FUNZIONAMENTO vi About This Manual This instruction book is arranged so that essential information on safety 15 contained in the front of the book Reading the Safety Precautions Section before operating the equipment is strongly advised The remainder of this manual 1s divided into Chapters and Sections Figures and tables are numbered sequentially within each chapter Chapter Layout Introduction Introduces the external features and and functions of the unit equipment provided and optons available Theory of Operation Describes the overall operation of the circuitry and the instrument functions Installation Provides information about connecting the instrument to your equipment Operation First time operators should
15. T ENDOMMAGER LE DISPOSITIF DE PROTECTION DE L INSTRUMENT IMPIEGO QUALORA QUESTO STRUMENTO VENISSE UTILIZZATO IN MODO DIVERSO DA COME SPECIFICATO DAL PRODUTTORE LA PROZIONE DI SICUREZZA POTREBBE VENIRNE COMPROMESSA SERVICE A 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 ELECTRICAS NO REALICE NINGUN SERVICIO A MENOS QUE ESTE CAPACITADO PARA HACERIO WARTUNG ANWEISUNGEN F R DIE WARTUNG DES GERATES GELTEN NUR F R GESCHULTES FACHPERSONAL ZUR VERMEIDUNG GEFAHRLICHE ELEKTRISCHE SCHOCKS SIND WARTUNGSARBEITEN AUSSCHLIEBLICH VON QUALIFIZIERTEM SERVICEPERSONAL DURCHZUFUHREN ENTRENTIEN L EMPLOI DES INSTRUCTIONS D ENTRETIEN DOIT TRE R SERV AU PERSONNEL FORME AUX OPERATIONS D ENTRETIEN POUR PR VENIR UN CHOC LECTRIQUE DANGEREUX NE PAS EFFECTUER D ENTRETIEN SI L ON N A PAS T QUALIFI POUR CE FAIRE UNITS ARE EQUIPPED WITH RECHAREABLE BATTERIES THESE ARE TO BE REPLACED BY AUTHORIZED SERVICE PERSONNEL ONLY LAS UNIDADES VIENEN EQUIPADAS CON BATERIAS RECARGABLES Y SOLAMENTE EL PERSONAL DE SERVICIO AUTORIZADO PUEDE REEMPLAZARLAS GERATE SIND MIT WIEDER AUFLADBAREN BATTERIEN BEST CKT BATTERIEN SIND NUR VON QUALIFIZIERTEM SERICE PERSONAL AUSZUWECHSELN
16. Watts Batteries 6 1 2 V NiMH C size Rechargeable Battery Life 12 hours approx Weight 5 3 4 lb 2 6 kg Frequency band and power range is determined by the Plug in Elements select ed See Bird Catalog for availability Some modes require two elements in a 10 1 power ratio VSWR and return loss functions settle in less than 1 second t For CW power levels greater than one third of full scale accuracy of the percent modulation mode is 5 from 0 to 90 and 10 from 90 to 100 Modulation fre quency is 25 to 100 000 Hz except for and B elements 25 to 20 000 Hz and H elements 25 10 000 Hz For and elements the minimum pulse width is 1 5 microseconds For H elements the minimum pulse width is 15 microseconds 34 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 Seller s sole obligation under these warranties shall be to issue credit repair or replace any item or part thereof which is proved to be other than as warranted no allowance shall be made for any labor charges of Buyer for replacement of parts adjustment or repairs or any other work unless such charges are authorized in advance by Seller If Seller s products are claimed to
17. adings when it 18 in milliwatts error message is displayed if power is more than 24 dB below or peak power is more than 6 dB above the nominal element range Refer to Table 4 Power dBm Power dBm 1 milliwatt 0 4 watts 36 10 milliwatts 10 10 watts 40 100 milliwatts 20 20 watts 43 1 watt 30 40 watts 46 2 watts 33 100 watts 50 The measurement of return loss is the same as that of SWR except that the result is displayed in dB In other words a reading of 21 65 indicates that reflected power is 21 6 dB down from forward power 15 Bird Model 4391A Power Analyst Insertion Loss or Attenuation Table 5 Correction Factors Monitoring Maximum and 16 Minimum Readings Attenuation or insertion loss can be measured directly using an external single port line section P N 4230 006 1 a dc feed in adapter P N 4381 050 and a dc cable P N 3170 058 6 The Model 43914 is inserted at the source end of the device being measured The second line section is inserted at the load end and its dc output 18 routed by the dc cable to the adapter inserted in the REFLECTED socket of the Model 4391A Both elements are in this case pointed in the direction of forward power flow If the two elements do not have a ten to one ratio a correction factor must be added to or subtracted from the return loss reading see Table 6 depending on the ratio of the elements Table 6 Correction Factors Ratio
18. are not Nickel Metal Hydride Do not install NiMH batteries that have less than 4600 mAh capacity Failure to comply may result in damage to the batteries damage to the instrument and injury to personnel from battery chemicals WARNING Use dry cleaning solvents in a well ventilated area Avoid excessive inhalation of solvent fumes since they can be toxic in heavy concentrations Always wear eye protection and avoid skin contact with the solvent WARNING Be sure that the power cable is unplugged before opening the wattmeter case The power supply capacitor C1 can retain a dangerous charge that must be removed before touching Always have another person standing by who is trained in electric shock first aid Caution Statements The following equipment cautions appear in the text whenever the equipment is in danger of damage and are repeated here for emphasis CAUTION Long term storage of this instrument can affect battery performance and reduce battery life Do not store the instrument for long periods of time without recharging the batteries refer to page 19 Failure to comply may result in reduced battery charge and shortened battery life CAUTION If the element cannot be fully inserted into the socket do not force it You might damage the element CAUTION Internal batteries are connected Remove one of the battery tubes before unsoldering wires connected to the Main PCB Failure to comply may result in
19. assembly from the output of calibrator source to the DC feed in adapter Set the RF Power Analyst range switches to the 10 and x100 positions Connect AC power and place the LINE OFF BATT switch to the LINE setting Figure 15 Calibration Potentiometer Maintenance 5 Switch on the Calibrator Source and let it warm up for at least one hour 6 Set the Calibrator Source to output 80 0 05 microamps 7 Adjust potentiometer R25 Figure 15 page 21 until the RF Power Analyst Displays 1000 5 FWD RFL PEP FWD RFL RTN dBm dBm LSS Element Wiper Contact Adjustment CAUTION If the element cannot be fully inserted into the socket do not force it You might damage the element Continuous insertion or rotation of the element might cause a slight change in the position of the contact spring in the element socket If the contact spring changes position you might experience erratic power readings You can use a small screwdriver to adjust the position of the contact spring Be careful not to bend the spring out so far that it interferes with insertion of the elements 21 Bird Model 4391A Power Analyst Perform the following steps to adjust the contact spring 1 Using a small flat head screwdriver place the flat side
20. ave Ratio SWR signal coming from the element whereas the Model 4391A uses peak and negative peak detector circuits to measure peak and minimum square root of power and combines them using the equation Peak Power Minimum Power CW POWER 2 With this technique operation of CW mode is predictable regardless of envelope shape see Figure 4 Operation of the reflected CW power mode is identical to that for forward CW power described above with two exceptions the readings are taken from the element in the socket marked REFLECTED and the range of the element 1s assumed to be 1 10 the range indicated by the range switches Two elements with a 10 to 1 power range ratio are required for this mode Press the SWR key momentarily If average forward power is between 10 and 12096 of the scale and the average reflected power is less than 120 of the reflected element range SWR will be displayed If any of the above conditions are not met an error message will be displayed Two arrows pointing to the right or greater than symbols indicate over range while two left pointing arrows or less than symbols indicate under range or too little power Refer to Table 2 Table 2 Voltage Standing Wave Ratio VSWR Measuring Peak Envelope Power Figure 9 Peak Envelope Power PEP Operating Instructions VSWR 1 01 1 02 1 03 1 04 1 05 1 06 1 07 1 08 1 09 1 10 1 15 1 20 1 2
21. be defective in material or workmanship or not to conform to specifications drawings blueprints and or samples Seller shall upon prompt notice thereof either examine the products where they are located or issue shipping instructions for return to Seller transportation charges prepaid by Buyer In the event any of our products are proved to be other than as warranted transportation costs cheapest way to and from Seller s plant will be borne by Seller and reimbursement or credit will be made for amounts so expended by Buyer Every such claim for breach of these warranties shall be deemed to be waived by Buyer unless made in writing within ten 10 days from the date of discovery of the defect The above warranties shall not extend to any products or parts thereof which have been subjected to any misuse or neglect damaged by accident rendered defective by reason of improper installation or by the performance of repairs or alterations outside of our plant and shall not apply to any goods or parts thereof furnished by Buyer or acquired from others at Buyer s request and or to Buyer s specifications Routine regularly required calibration is not covered under this limited warranty In addition Seller s warranties do not extend to the failure of tubes transistors fuses and batteries or to other equipment and parts manufactured by others except to the extent of the original manufacturer s warranty to Seller The obligations under the for
22. e Switches and Display Group 3 Elements Analog Circuitry and A D Converter 3 Installation sammal a 7 Operating on AC 7 8 Operating Instructions 11 Operating Modes 11 Reading Forward CW Power 11 Reading Reflected CW Power 12 Reading 12 Measuring Peak Envelope Power 13 Measuring Amplitude Modulation 14 Measuring Power 15 Measuring Return Loss 15 Insertion Loss or Attenuation 16 Monitoring Maximum and Minimum Readings 16 Using the Peaking Aid 17 Battery 18 19 Preventive Maintenance 19 Cleaning and 19 Long term Storage 19 Calibration oll vere dd va 20 Required Eguipment 20 Initial 20 Element Wiper Contact Adjustment 21 Troubleshooting 23 General EX LE en Cy e tee 23 Disassembly 2 2c ssepe 24 Front Panel Removal 24 Main Printed Circuit PC Board Removal 25 QC Connectors Removal 26 Line Section 27 Batte
23. e element wiper Loose hold down catch Worn line section Defect on Data Acquisition PC board assembly Replace defective elements Adjust the element wiper contact Refer to page 21 Readjust catch to hold element securely in place Replace line section Refer to page 27 Replace the PC board assembly attached to line section Refer to page 27 and either page 31 or page 32 High standing waves Dirty Connectors Worn or damaged connectors Foreign objects in line section Clean the connectors Replace the connectors Refer to page 27 Remove object from the line section Short battery life 115 230V switch in wrong position Damaged worn batteries Set 115 230V switch to correct position Replace the batteries Will not operate from AC line 115 230V switch in wrong position Blown fuse Defective line cord Set 115 230V switch to correct position Replace blown fuse Figure 5 page 7 and Figure 24 page 30 Repair or replace 23 Bird Model 4391A Power Analyst PROBLEM POSSIBLE CAUSE REMEDY Display Element wiper not Readjust the element wiper to indicates 0 contacting the element make good contact page 21 Power Defective Plug in Replace Plug In Element Element Defect on Data Replace the PC board Acquisition PC board assembly attached to line assembly section Refer to page 27 and either page 31 or page 32 One s
24. egment of a display doesn t light Defective Display Replace the display decimal points stay lit Low charge on the Recharge the batteries batteries Replace the Main circuit board assembly Refer to page 25 Defective circuit component Same segment on all displays doesn t light Replace the Main circuit board assembly Refer to page 25 Defective circuit component One or more keys do not function Defect on Main PC board Replace the Main circuit board assembly Disassembly WARNING Be sure that the power cable is unplugged before opening the wattmeter case The power supply capacitor C1 can retain a dangerous charge that must be removed before touching Always have another person standing by who is trained in electric shock first aid Front Panel Removal 24 CAUTION This instrument contains static sensitive electronic components Before opening or servicing the unit make sure that you understand and practice electrostatic discharge component handling Failure to comply may result in permanent damage to sensitive components Disconnect AC power from the instrument Remove the six screws that secure the front panel to the Main PCB supports Figure 18 page 25 item 1 Remove the two screws and lock washers that secure the front panel at the bottom of the housing item 2 Remove the two screws and lock washers that secure the front panel at the back of
25. egoing warranties are limited to the precise terms thereof These warranties provide exclusive remedies expressly in lieu of all other remedies including claims for special or consequential damages SELLER NEITHER MAKES NOR ASSUMES ANY OTHER WARRANTY WHATSOEVER WHETHER EXPRESS STATUTORY OR IMPLIED INCLUDING WARRANTIES OF MERCHANTABILITY AND FITNESS AND NO PERSON IS AUTHORIZED TO ASSUME FOR SELLER ANY OBLIGATION OR LIABILITY NOT STRICTLY IN ACCORDANCE WITH THE FOREGOING
26. harge until the decimal points light before recharging If the batteries lose the ability to hold a charge they should be replaced See Chapter 5 Maintenance for important precautions regarding static electricity when opening the housing WARNING Use only NIckel Metal Hydride NiMH batteries that have a minimum capacity of 4600 milliamper hours mAh Do not install batteries that are not Nickel Metal Hydride Do not install batteries that have less than 4600 mAh capacity Failure to comply may result in damage to the batteries damage to the instrument and injury to personnel from battery chemicals CAUTION Long term storage of this instrument can affect battery performance and reduce battery life Do not store the instrument for long periods of time without recharging the batteries refer to page 19 Failure to comply may result in reduced battery charge and shortened battery life Cleaning and Inspection Long term Storage Chapter 5 Maintenance The 4391A RF Power Analyst was designed and built to provide many years of trouble free service This section provides the information needed to prevent and correct equipment failure Preventive Maintenance To avoid unnecessary damage always observe the following cautions 1 TheRF Power Analyst is a rugged and portable instru ment intended for field use However it should not be unnecessarily exposed to extreme environmental condi tions 2
27. le For specified accuracy the average CW power levels must be greater than one third of full scale Modulation is calculated as follows MODULATION Power Minimum Bower x 100 Peak Power Minumum Power and is therefore limited to the range of 0 to 99 9 percent Over modulation will be indicated as 99 9 percent Refer to Table 3 Peak Modulation Peak Modulation CW Power CW Power 1 00 0 2 40 55 1 10 5 2 56 60 1 21 10 2 72 65 1 32 15 2 89 70 1 44 20 3 06 75 1 56 25 3 24 80 1 69 30 3 42 85 1 82 35 3 61 90 1 96 40 3 80 95 2 10 45 4 00 100 2 25 50 Because of the threshold of the RF diode a modulated signal which has a minimum power level below 0 3 percent of full scale will result in high modulation reading with uncertain accuracy Measuring Power in dBm Figure 11 CW Power in dBm Table 4 Watts dBm Equivalents Measuring Return Loss Figure 12 Return Loss Insertion Loss or Attenuation Operating Instructions Operation of the forward and reflected dBm modes is identical to the forward and reflected CW power modes except that the resulting reading is converted to dB above 1 milliwatt before it is displayed It should be noted that in doing this conversion the range set on the slide switches is assumed to be watts rather than kilowatts or milliwatts If it 1s not 30 0 must be added to all dBm readings when the range is in kilowatts or subtracted from all re
28. letely discharge the batteries 19 Bird Model 4391A Power Analyst Required Equipment Table 7 Required Calibration Equipment Initial Setup 20 then perform a full charge again If necessary repeat this discharge and charge cycle up to three times If the batteries do not remain charged after three discharge charge cycles replace the batteries WARNING Use only NIckel Metal Hydride NiMH batteries that have a minimum capacity of 4600 milliamper hours mAh Do not install batteries that are not Nickel Metal Hydride Do not install batteries that have less than 4600 mAh capacity Failure to comply may result in damage to the batteries damage to the instrument and injury to personnel from battery chemicals Calibration The RF Power Analyst should be calibrated once each year or after any repair Refer to Table 7 for test equipment needed to calibrate the RF Power Analyst Equipment Recommended Model Calibrator Source Keithly Model 263 or equivalent Cable Assembly 1 Required BNC to BNC 1 meter long DC Feed in Element 1 required Bird Electronic 4381 050 On a clean flat workspace perform the following setup procedure 1 2 Remove the front panel Refer to Front Panel Removal on page 24 Insert a DC feed in adapter into the FWD element of the socket Insert a metal dust plug supplied with the instrument into the RFL element socket Connect a BNC to BNC cable
29. mode If the unit is already operating the forward CW power mode is selected by pressing the FWD CW key momentarily If the applied power exceeds 120 percent of the range two right facing arrow heads i e greater than symbols will be displayed The operation of this error message does not depend on the correct setting of the range switches by the operator nor will the meter or its elements be damaged if the switches are incorrectly set CAUTION Never apply RF power to the Model 4891A Wattmeter unless both line section sockets are filled with either an element or a dust plug If an element is used it is advisable to place the element with the arrow at a 90 angle to the coaxial line CAUTION Always disconnect ac power before opening the Model 4391A enclosure Removal of at least one battery cell is also recommended when servicing the instrument The Model 4391A arrives at values of CW power by a method quite different from analog meters such as the Model 43 also manufactured by Bird Electronic While the two instruments will agree when the measured wave is of constant amplitude AM or SSB waves will result in different indications in the CW mode This is because the analog instrument uses the inertia of the microammeter to time average the varying 11 Bird Model 4391A Power Analyst Reading Reflected CW Power Figure 7 Reflected Power CW Reading SWR 12 Figure 8 Standing W
30. nected at some convenient point to permit the Model 43914 air line to be inserted Although the Model 4391A is normally supplied with two Female N type connectors a variety of easily interchangeable connectors are available to facilitate connecting to the user s system Once the Model 43914 is installed in the coaxial line a Plug in Element or a pair of Plug in Elements must be selected which correspond to the frequency and power levels to be measured I NOTE The instrument is shipped with dust plugs installed in the element sockets Remove the dust plugs to insert elements In order to take full advantage of the Model 4391A s capabilities two elements in a 10 1 ratio of power range should be used If only one element is used the other socket should be filled with a dust plug or a higher power element Also for greatest accuracy the element s should be chosen having the lowest possible power range that will not result in over ranging Table 1 lists elements required for each mode of operation Mode Forward Reflected FWD CW RFL CW Y SWR Y v FWD PEP RFL PEP MOD FWD dBm RFL dBm Loss JE The reflected element must have a nominal power range one tenth that of the forward element The higher power element is placed in the socket marked FORWARD and its arrow pointed in the direction of forward power flow toward antenna or load The lower power element
31. o 44139 2794 Phone 440 519 2298 Fax 440 519 2326 E mail bsc bird technologies com For the location of the Sales Office nearest you give us a call or visit our Web site at http www bird electronic com 33 Bird Model 4391A Power Analyst Specifications Measuring Medium RF Transmission in 50 ohm lines RF Power Range 100 mW to 10 kW full scale using Bird Plug in Elements Accuracy not guaranteed with components not supplied by Bird Usable Over Range To 120 of scale on CW PEP SWR and Return loss functions To 400 of scale PEP on dBm and 0 modulation Freguency Range 450 kHz to 2 7 GHz Sampling Range 2 3 readings per second Settling Time 10 seconds worst case Accuracy Power Readings PEP SWR Modulation Return Loss Impedance 5 of full scale 8 of full scale 10 of reading 5 0 3 dB to corresponding SWR value 50 ohms Insertion SWR 1 05 max to 1000 MHz Pulse Parameters square pulses Pulse Width Repetition Rate Duty Cycle 0 8 psec min 25 pps min 0 01 min RF Line Connections Standard Bird Quick Change QC Female N Optional Any Standard AN QC type Temperature Range Operating 10 C to 45 C 50 F to 113 F Storage 20 C to 45 C 4 F to 113 F Input Power Requirements Voltage 100 130 or 200 230 VAC Switch Selectable or 7 2 Vdc internal battery Frequency 50 60 Hz Power 6
32. o the housing Figure 20 item 1 Removal 2 Remove the two QC connectors item 2 by pulling them away from the line section assembly 26 Line Section Removal Figure 20 Removing QC Connectors and Line Section 1 2 Maintenance Remove the QC connectors page 26 Remove the four screws and lock washers that secure line section assembly to the housing item 3 Using minimum pressure spread apart the sides of the lower housing assembly just far enough to allow the line section assembly to be removed 1 Tm ra ON y sl SS 10 tem o E 4 IE mod To remove the line section PCB continue with the next steps CAUTION This instrument contains static sensitive electronic components Before opening or servicing the unit make sure that you understand and practice electrostatic discharge component handling Failure to comply may result in permanent damage to sensitive components Remove the two screws units with serial numbers 1723 and below or the two hex nuts units with serial numbers 1724 and above Figure 21 item 5 that secure the PCB cover then remove the cover item 6 and spacers item 7 Disconnect the ribbon cable assembly from the PC board header J1 27 Bird Model 4391A Power Analyst Figure 21 Removing Line Section PCB Battery Replacement 28 ow Remove the
33. of Added dB Ratio of Added dB Elements Elements 1 1 10 100 1 10 2 1 7 200 1 13 2 5 1 6 250 1 14 4 1 4 400 1 16 5 1 3 500 1 17 10 1 0 1000 1 20 20 1 3 2000 1 23 25 1 4 2500 1 24 40 1 6 4000 1 26 50 1 7 5000 1 27 While operating in any of the modes described the Model 4391A will continuously keep track of the highest and lowest reading obtained This action begins after ten reading cycles to allow time for the peak detectors to settle from the previous mode To recall the maximum or minimum reading depress and hold the MAX or MIN key When these keys are released the meter goes back to displaying the current value of the parameter being measured Recalling max or min does not stop the meter from continuing to monitor the current value and updating the minimum and maximum registers To clear the minimum and maximum register the mode key must be pressed again or a new mode selected For example if CW power deviations are monitored the Model 4391A is installed as described at the beginning of this section and turned on then the power source is turned on and allowed to stabilize Once the system has stabilized press FWD CW to clear the MAX and MIN registers At any time during test the MAX and MIN keys can be used to recall the maximum and minimum values without affecting the test However pressing the FWD CW key or changing modes will clear the registers Figure 13 Maximum or Minimum Readings Using the Peaking
34. of the screwdriver behind the contact bar as 1ndicated and bend the contact bar so that the contact rests in the center of the slot adjacent to the element socket Figure 16 Figure 16 Adjust Element Contact Up and Down 2 After centering the contact bend it slightly toward the center of the element socket bore so that the profile of the element contact is visible when viewing the element socket from the top of the socket bore Figure 17 Figure 17 Adjust Element Contact In and Out 3 If the contact is accidently moved too far into the element bore the element will not slide into the socket Move the contact back into the recessed area and repeat the process 22 Maintenance Troubleshooting General The troubleshooting instructions are intended to aid in fault isolation This is accomplished through the use of a troubleshooting table First locate the symptom s in the problem column of Table 8 In some cases the same fault can have more than one symptom and more than one possible remedy Compare the possible causes until you arrive at a suspected fault Once a fault has been isolated repair or replace the defective components I NOTE Always recalibrate the RF Power Analyst after repairing the fault Table 8 Trouble shooting PROBLEM POSSIBLE CAUSE REMEDY Inaccurate RF Power Analyst Recalibrate power readings uncalibrated Defective Plug in Elements Intermittent connection at th
35. permanent equipment damage and severe shock to individuals CAUTION Never apply RF power to the Model 4391A Wattmeter unless both line section sockets are filled with either an element or a dust plug If an element is used it 1s advisable to place the element with the arrow at a 90 angle to the coaxial line CAUTION Always be certain the 115 230 voltage selector is set to the proper voltage before ac power is applied CAUTION Always disconnect AC power before opening the Model 4391 enclosure Removal of at least one battery cell is also recommended when servicing the instrument CAUTION This instrument contains static sensitive electronic components Before opening or servicing the unit make sure that you understand and practice electrostatic discharge component handling Failure to comply may result in permanent damage to sensitive components Bird Model 4391M Power Analyst Safety Statements USAGE N 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 PROTECCION DE SEGURIDAD DEL INSTRUMENTO BENUTZUNG WIRD DAS GERAT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN KANN DIE GERATESICHERHEIT BEEINTRACHTIGT WERDEN UTILISATION TOUTE UTILISATION DE CET INSTRUMENT QUI N EST PAS EXPLICITEMENT PREVUE PAR LE FABRICANT PEU
36. read Chapter 1 Introduction Chapter 2 Theory of Operation and Chapter 3 Installation to get an overview of equipment capabilities and how to install 1t Experienced operators can refer to Chapter 4 Operating Instructions All instructions necessary to operate the equipment are contained in this section Maintenance personnel should be familiar with calibration and repair information found in Chapter 5 Maintenance If a failure should occur the troubleshooting section will aid in isolating and repairing the failure Parts For location of major assemblies or parts refer to the part lists and associated drawings Changes to this Manual We have made every effort to ensure this manual is accurate at the time of publication If you should discover any errors or if you have suggestions for improving this manual please send your comments to our factory This manual may be periodically updated when inquiring about updates to this manual refer to the part number and revision level on the title page vii Bird Model 4391M Power Analyst viii Table of Contents Safety Precautions i About This Manual vii 1 Purpose and Function 1 Description 2 Theory of Operation 3 Description 3 Keyboard Rang
37. rived from rechargeable nickel metal hydride batteries inside the unit or from a 115 230 VAC power source connected to the unit through the power cord supplied with the unit L 62 32 4 158 0mm Di _ 4 21 64 109 9mm 4 3 4 l 120 7mm ELEMENT _ RANGE 25 0 10 x 5 x100 TE 243 3mm Description of Operation Figure 2 Circuit Block Diagram Keyboard Range Switches and Display Group Elements Analog Circuitry and AID Converter Chapter 2 Theory of Operation Figure 2 is a block diagram of the major functional parts of the Model 4391A RF Wattmeter The Microcomputer integrated circuit shown controls all the other portions of the instrument which fall into two major groups Forward Directional Element Peak Detector Neg Peak Detector Reflected Directional gt Element Analog to Digital Converter Switches Switches Switches Digit Display 17 Keyboard Single Chip Computer Range Switches The keyboard and range switches serve only to pass information to the computer The display of course returns information from the computer to the operator The display which is comprised of four seven segment LED digits is strobed digit by digit left to right at a rate of approximately one digit per millisecond This serve
38. ry Replacement 28 Parts List eis VE at is 30 Customer 33 Specifications 34 Purpose and Function Chapter 1 Introduction The Model 4391A is a multi purpose Radio Frequency wattmeter designed around a microcomputer program stored in permanent memory controls the operation of the instrument at all times permitting the detection and correction of various error sources and the refinement of the raw data produced by the directional detectors The instrument can compute VSWR amplitude modulation and various decibel variables reducing the odds of error and making such measurements consistent or repeatable regardless of who makes the measurement Other benefits include extended range using standard elements in some modes of operation continuous monitoring of maximum and minimum readings a peaking aid and error messages Because of its complexity the proper use of the 43914A is not always obvious For this reason it is strongly advised that this manual be read in its entirety before using the device The 4391A RF Power Analyst is an insertion type digital RF Directional Thruline amp Wattmeter designed to measure peak or average power flow load match and amplitude modulation in 50 ohm coaxial transmission lines It 1s intended for use with CW AM FM SSB TV and Pulse modulation envelopes The instrument directly reads PEP or CW power in
39. s to conserve battery power and drive circuitry while providing scanning for the columns of the keyboard Each time a digit is strobed the corresponding column of the keyboard is read and if a key is pressed the computer puts the code for that key into a memory cell The nine mode keys select which parameter is to be measured The three modifier keys simply modify the way in which the result is displayed The range selector switches identify to the computer the nominal full scale values of the elements used They have no effect on input sensitivity which is determined by the elements These components are controlled by the computer The Plug in Elements in the line section provide low level positive voltages related to the instantaneous value of power see Figure 3 The first group of solid state switches selects the forward element the reflected element or ground as the input to the preamplifier which boosts these signals to 0 1 to 2 0 volt range The remaining switches shown as two groups direct the output of the preamp to the analog to digital converter either directly or through a peak or negative peak detector The analog to digital converter converts the voltage to a 15 digit binary number Bird Model 4391A Power Analyst Each reading output by the display is derived from up to three voltage readings using the circuitry described above Once these voltages are measured all remaining operations are performed within the computer chip
40. two screws item 4 that secure the PCB to the line section then pull the PC board assembly item 3 away from the line section subassembly Remove the item 2 Remove keying beads item 1 from the element wiper contacts on the PC board assembly toe iii M Remove the front panel refer to Front Panel Removal on page 24 Remove the four screws and lock washers Figure 22 item 1 that secure the Main PCB Loosen but do not remove the remaining two screws that secure the Main PCB item 2 Tilt the Main PC board assembly up to expose the bat teries then tighten the two screws to secure the PCB Unfasten the velcro strap and remove it from the D ring Figure 23 Note the polarity orientation of the batteries Remove the three battery tubes from the battery clips then remove two batteries from each tube Install new batteries into the tubes then secure the tubes in the battery clips Be sure to observe proper polarity Figure 22 Tilt Main PCB to Expose Batteries Figure 23 Battery Replacement 10 Maintenance Lower and secure the Main PC board assembly Replace and secure the front cover Charge the batteries for 16 hours before using the instrument Velcro Straps Battery Tubes 29 Bird Model 4391A Power Analyst Figure 24 Parts Drawing Item No Figure 24 1
41. y dangerous Avoid inhalation of fumes or prolonged contact with skin Safety Earth Ground An uninterruptible earth safety ground must be supplied from the main power source to test instruments Grounding one conductor of a two conductor power cable is not sufficient protection Serious injury or death can occur if this grounding 15 not properly supplied Resuscitation Personnel working with or near high voltages should be familiar with modern methods of resuscitation Safety Symbols WARNING Warning notes call attention to a procedure which if not correctly performed could result in personal injury Bird Model 4391M Power Analyst CAUTION Caution notes call attention to a procedure which if not correctly performed could result in damage to the instrument The caution symbol appears on the equipment indicating there is important information in the instruction manual regarding that particular area I NOTE Calls attention to supplemental information Fuse Replacement Always use the same type and rating of fuse when replacing the fuse Fuse information can be found in the parts list on page 30 Warning Statements The following safety warnings appear in the text where there is danger to operating and maintenance personnel and are repeated here for emphasis WARNING Use only NIckel Metal Hydride NiMH batteries that have a minimum capacity of 4600 milliamper hours mAh Do not install batteries that
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