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 applied to all phases of operation and maintenance.
Bird AT-400 Antenna Tester Shock Hazard Do not attempt to remove the RF transmission line while RF power is present. Radiated RF power is a potential health hazard. Safety Symbols Warning notes call attention to a procedure which, if not correctly performed, could result in personal Caution notes call attention to a procedure which, if not correctly performed, could result in damage to The caution symbol appears on the...
Warning Statements The following equipment warnings appear in the text whenever there is a danger to people. Live RF energy. Do not touch or ground the center conductor of a live RF connection. Failure to comply may result in equipment damage and serious burns or death to personnel.
Bird AT-400 Antenna Tester 250mW max. input Exceeding the maximum input will cause damage to internal components. Do not connect transmitter output to the AT-400. Damage can also be caused by testing antennas near other transmitting antennas. If testing base station antennas, first measure the power at the coax end to be sure it does not exceed 250mW.
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ANULAR LA PROTECCIÓN DE SEGURIDAD DEL INSTRUMENTO. BENUTZUNG WIRD DAS GERÄT AUF ANDERE WEISE VERWENDET ALS VOM HERSTELLER BESCHRIEBEN, KANN DIE GERÄTESICHERHEIT BEEINTRÄCHTIGT WERDEN. UTILISATION TOUTE UTILISATION DE CET INSTRUMENT QUI N’EST PAS EXPLICITEMENT PRÉVUE PAR LE FABRICANT PEUT ENDOMMAGER LE DISPOSITIF DE PROTECTION DE L’INSTRUMENT.
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Bird AT-400 Antenna Tester WARTUNG ANWEISUNGEN FÜR DIE WARTUNG DES GERÄTES GELTEN NUR FÜR GESCHULTES FACHPERSONAL. ZUR VERMEIDUNG GEFÄHRLICHE, ELEKTRISCHE SCHOCKS, SIND WARTUNGSARBEITEN AUSSCHLIEßLICH VON QUALIFIZIERTEM SERVICEPERSONAL DURCHZUFÜHREN. ENTRENTIEN L’EMPLOI DES INSTRUCTIONS D’ENTRETIEN DOIT ÊTRE RÉSERVÉ AU PERSONNEL FORMÉ AUX OPÉRATIONS D’ENTRETIEN. POUR PRÉVENIR UN CHOC ÉLECTRIQUE DANGEREUX, NE PAS EFFECTUER D’ENTRETIEN SI L’ON N’A PAS ÉTÉ...
About This Manual About this Manual Many people read the operators manual only as a last resort. If you are one of those people, you should at least read the next two pages so that you can find the information when you do need it. You will also learn where to find valuable time saving information.
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Bird AT-400 Antenna Tester Chapter Layout Introduction—Will help you become familiar with the parts of the Antenna Tester, Features Available, and Optional Equipment. Basic Operation—Everyone should read this section! This section will provide the information required to get the Antenna Tester powered up, and provides helpful information about how to operate the Antenna Tester, and some time saving hints for alternate operating methods.
Bird AT-400 Antenna Tester Component Description Figure 2 Component Description LCD Display External DC Connector Backlit liquid crystal display. Connect either the ac adapter or the cigarette lighter adapter. External supplies operate the unit and charge the internal battery.
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Cursor Keys Left Arrow Right Arrow Up Arrow Down Arrow Backlight Key On Key +/- Key Enter Key ESC Key Menu Key 10. Select Key 11. Numeric Keys 12. Menu Select Keys 13. Test Port 14. Serial Port Press in swept frequency mode to move the cursor to the left.
Bird AT-400 Antenna Tester Display Description VSWR 65.00 Band Meas Units Freq Units Figure 3 Display Description 1.35 260.00 MHz Busy 520.00 Sweep Trace Limit Type 1.35 260.00 Mhz VSWR Batt Auto Manual Audio Scale Scale...
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Sweep Rate Indicator Measurement Units Trace Menu Select Key Labels Frequency Band Scale Cursor Utility Label Frequency Measured Value 10. Scale 11. Pointer Blinks when sweeping. Indicates selected measurement units. Graphic display of measured results across selected frequency band. Defines function of menu select keys located below the display.
Bird AT-400 Antenna Tester Features ρ Swept Frequency Mode — Fast scan shows VSWR, match efficiency or return loss across an entire band. A movable cursor can be used to pinpoint a scan frequency and the corresponding measurement value is displayed. Single Frequency Mode —...
Introduction Optional Equipment Automobile Cigarette Lighter Adapter — (P/N 5A2238-1) Connects tester to standard 12V automotive cigarette lighter jack. Carrying Case — (P/N 5000-030) Convenient and protective, large enough to carry the tester, AC adapter, connectors, field strength antenna and instruction book. Verification Kit —...
Chapter 2 Getting Started This section describes initial quick steps to get started. For detailed information regarding connecting the Antenna Tester refer to that section at the end of this chapter. Note: This unit is shipped with the batteries not charged.
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Bird AT-400 Antenna Tester Blinking Cursor (black square) The cursor will be blinking in the selected area, indicating that the parameter for that area can be changed. Enter Key ENTER All data entry, and mode changes accessed using select key, require the enter key to be pressed before they are initiated.
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Messages There are five utility messages that can be displayed to inform you of equipment, or procedural, conditions. “Lo Batt” is displayed when battery voltage is less than 6.6V, refer to maintenance section for charging batteries. “Busy” is displayed during mode changes indicating the measurement information is being updated.
Bird AT-400 Antenna Tester Return to Factory Presets When the Antenna Tester is turned on, the various software parameters will be set to the condition they were at when the tester was turned off. To return the parameters to the factory setting follow the steps below.
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Set Serial Baud Rate Measurement data can be transferred between the AT-400 and a personal computer using the serial port and optional interface software. The data can then be used for analysis, printed, or stored. The data transfer rate (baud rate) between the Antenna Tester and computer must be identical and set to 9600.
Chapter 3 The following paragraphs will explain how to connect the Bird Antenna Tester for various operations. Refer to the component description diagram on page 2 if needed. Power Supply The AT-400 can use an external power source. Using the ac adapter or the 12V cigarette lighter adapter will also charge the battery.
Bird AT-400 Antenna Tester Connecting the Antenna Live RF energy. Do not touch or ground the center conductor of a live RF connection. Failure to comply may result in equipment damage and serious burns or death to personnel. Use proper Electrostatic Discharge (ESD) precautions to avoid static discharge when making connections to the test port.
Chapter 4 Understanding the Operating Modes The Antenna Tester is connected and the operating frequency band is selected (see basic operation). User selections are customized, the power is on, and the top level menu is displayed (also in basic operation). Now what? Before we explain how to measure the antenna match, a brief discussion of your options is in order.
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Bird AT-400 Antenna Tester Figure 5 Single Frequency Measurement Units Rho (Reflection Coefficient), VSWR (Voltage Standing Wave Ratio), Match Efficiency (%), and Return Loss (dB), are different units of measurement that can be used to present the same information. (Similarly, Celsius and Fahrenheit are different units of measurement used to express the same temperature).
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Antenna manufacturers often use VSWR for specifications. Match Efficiency is popular for testing because it is easy to determine a good match versus a bad match. For example a system with a VSWR of 1.50 would show -13.98 dB Return Loss and 96% Match Efficiency.
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Bird AT-400 Antenna Tester In the single frequency mode Auto Scaling sets the measurement unit scale so the pointer is mid range of the previous reading. The maximum and minimum scale values are approximately 10% higher or lower than the measured value.
Swept Frequency Select Frequency Band There are two options for selecting the frequency band. The first is simply to enter the start and stop frequencies. The second is to enter a span frequency, which is the desired width of the band, and a center frequency, that will be used as the center of the band.
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Bird AT-400 Antenna Tester Select Measurement Units Antenna match information can be presented using four different measurement units. Depending on your application, follow the steps below to select Rho, VSWR, %Match or Return Loss. Press the MENU key. Press the SWEPT FREQ key. Press the MEAS UNITS key.
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NOTE: If an out of range value is entered, the minimum (if under-range) or maximum (if over-range) value will be substituted. If a maximum value that is lower than the minimum value is entered, the cursor will blink again on the minimum value waiting for a correct entry. The actual range depends on the units selected.
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Bird AT-400 Antenna Tester comparison. For example, if you save a trace displayed in VSWR, you can compare it to a trace displayed in %Match. You can also change the frequency band of the new trace to effectively zoom in on a particular section of the saved trace. This may be helpful in pinpointing a problem area in a failed limit test.
Press the MENU key. Press the SWEPT FREQ key. Press the TRACE key. Press the RECALL TRACE key. Press the REG-n key for the desired trace, press the MORE RECALL key to access 5-8 and again to access 9-12. If needed, use the ESC key to back up. The saved trace will be displayed and the corresponding register number will be shown at the bottom of the display.
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Bird AT-400 Antenna Tester or fail will be displayed at the top of the display and an audible tone can be enabled to indicate a fail situation. Limit testing is probably the most labor-efficient mode for operating the AT-400. Since all the software settings are retained when the tester is turned off, once the limit test is set up its simply a matter of connecting the next antenna system, turning on the power and reading pass or fail.
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Using a Trace as the Limit The trace you want to use for the limit must be saved. You can have the current antenna test running or start it after you set up the limit test. Figure 11 Dotted Outline of Limit Trace Press the MENU key.
Bird AT-400 Antenna Tester Clearing a Limit Follow the steps below to clear either an operator defined limit value or a trace limit. The trace will still be stored in memory, the limit value will be erased. Press the MENU key. Press the SWEPT FREQ key.
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Select Measurement Units Antenna match information can be presented using three different measurement units. Depending on your application, follow the steps below to select Rho, VSWR, %Match or Return Loss. Press the MENU key. Press the SINGLE FREQ key. Press the UNITS key. Press either the RHO, VSWR, %MATCH or RETURN LOSS key.
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Bird AT-400 Antenna Tester NOTE: If an out of range value is entered, the minimum (if under-range) or maximum (if over-range) value will be substituted. If a maximum value that is lower than the minimum value is entered the cursor will blink again on the minimum value, waiting for a correct entry.
Chapter 5 Field Strength Measurement With the field strength antenna installed, the Antenna Tester can be used to optimize the radiated signal of any transmitter from 65 to 520MHz. This is a relative measurement. The measurement sensitivity is such that a full scale deflection will occur for a field of 0.22 Volts/Meter at 400 MHz.
Chapter 6 Cleaning Harsh or abrasive detergents and some solvents can damage the display unit and information on labels. Clean the antenna tester and the display with a soft cloth dampened with mild detergent and water only. Calibration For best performance and accuracy, the Antenna Tester should be calibrated once every 12 months.
Bird AT-400 Antenna Tester Operational Tests Power-up There are several operational tests run at power up. The test is displayed only if any of the tests fail. The results are displayed to the right of the test as shown in Figure 12. If you would like the test screen displayed regardless of results, press any key while pressing the ON key at initial power up.
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Battery Test The battery test checks the output voltage of the batteries. The result is displayed in a simulated analog meter type graphic with the value shown at the top of the display. The scale is set from 6-8V. If the voltage measured is less than 7V you should charge the batteries.
Bird AT-400 Antenna Tester Figure 14 Display Test Press the MENU key. Press the TEST key. Press the DISP TEST key. The test is started. Press the ESC key to end the test. Self Test The self test is similar to the operational tests run at power up described on page 34, except for the keypad test.
To test the keypad, Press each key (except ESC and ON). The value next to Keypad is hexadecimal and corresponds to the key pressed. If the value does not change for each key, refer to Troubleshooting in this section. Press the ESC key to stop the test. Battery Replacement The NiCad batteries need to be replaced when fully charged batteries provide less than 2 hours operation.
Bird AT-400 Antenna Tester Replace the six screws. 10. Run the battery test on page 35 of this section. Fuse Replacement Replace with only the same type and rating fuse. 315mA Follow the steps outlined in Battery Replacement replacing the fuse where replacing the batteries is indicated.
Maintenance Troubleshooting Operator maintenance or service is limited to battery and fuse replacement. Any other required service must be performed at at an authorized Bird Service Center. Refer to the following paragraphs for help in isolating error conditions. The Antenna Tester will not power up. Power for the Antenna Tester can be provided in three ways—the internal batteries, an AC mains adapter or an optional automobile cigarette lighter adapter.
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Bird AT-400 Antenna Tester ROM, EEPROM, RAM, A/D, TEMPR, PLL Test Fails Ensure the results are valid by repeating the self test or turning the unit off then back on. If the problem persists return the unit for service. Stuck Keys Test Fails If any characters other than 0 are displayed next to stuck keys during power up test, perform the keypad test on page 36 of this section.
to a perfect match. Measurement results are not accurate under these circumstances. The remedy is to disable the interfering source, if possible, or postpone the measurement to a time when the interfering source is not operating. Customer Service Any maintenance or service procedure beyond the scope of those in this chapter should be referred to a qualified service center.
Bird AT-400 Antenna Tester Parts List Part Name AT-400 Complete Parts Supplied with AT-400 Complete, or installed when shipped. Battery (6 required) Fuse AC Mains Adapter, 115v AC Mains Adapter, 230v Female N Connector Field Strength Antenna Instruction Book Foam Shock Strips (2) Optional Adapters: BNC/m BNC/f...
Specifications Frequency Range Frequency Resolution Measurement Range VSWR Match Efficiency 0 to 100% Return Loss Measurement Speed Single Frequency 5 Readings/second Swept Frequency 1 Sweep/second Test Port Impedance Connector Field Strength Range Sensitivity Power Requirements Batteries External DC External AC Adapter Interface Operating Temperature Storage Temperature...
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;...
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