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NARDA 8718B User Manual

Electromagnetic radiation survey meter
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P/N 42983600 RevB
USER'S GUIDE
Model 8718B
Electromagnetic
Radiation
Survey Meter
narda
Safety Test Solutions
L
an
3
communications company

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  • Page 1 P/N 42983600 RevB USER'S GUIDE Model 8718B Electromagnetic Radiation Survey Meter narda Safety Test Solutions communications company...
  • Page 2 About the Model 8718B Getting Started with the Model 8718B It is important to become familiar with the Model 8718B before you use it. Chapter 2 explains the basic meter hardware. Chapters 3 and 4 cover probe selection and basic operation.

  • Page 3: Equipment Supplied

    Using this Guide with a Model 8718 The Model 8718 can be upgraded to take advantage of most, but not all, of the improvements incorporated into the Model 8718B. The upgrade includes some minor hardware changes and the installation of the Version 3.0 firmware that is described in this guide.

  • Page 4: General Description

    Understanding Your Model 8718B General Description It is important to be familiar with the Model 8718B before you use it. This section includes descriptive data keyed to highlighted illustrations to help you locate the various features of the meter. The descriptions not only identify the features but tell you how they are used.

  • Page 5: Audio Alarm

    Your Model 8718B is equipped with an audible alarm that emits sound through a tiny hole on the bottom of the meter. The alarm sounds whenever the field strength exceeds the measurement range of the probe (over ranges).

  • Page 6: Operation With A Computer

    Chapter 2 Understanding Your Model 8718B A strap is provided on the underside of the Model 8718B. It has a hook and loop closure to permit easy adjustment, around your hand. Behind the strap is a threaded connector used to secure the meter to a tripod.

  • Page 7: Power Keys

    Keypad The Model 8718B has four groups of keys distinguished by their color. The keys on the 8718B must be firmly depressed to per- form their function and give a tactile feedback when prop- erly depressed. Power Keys Function Keys...

  • Page 8: Special Function Keys

    Numeric Keypad Use the numeric keypad to enter number data into the Model 8718B. You also use the numeric keypad to select a numbered option listed on the display screen. Special Function Keys Six special function keys enable you to perform specific functions.
  • Page 9 Operating the Meter...

  • Page 10: Key Factors In Selecting A Probe

    Probe Selection Introduction The 8700 series RF measurement system offers a very broad selection of probes. The factors that you should consider in selecting the probe, or probes, best suited for your task are described in this section. Key Factors in Selecting a Probe The probe frequency range should include the frequencies of all FREQUENCY the emitters to be surveyed at one time.
  • Page 11 Flat response probes are the most common. Narda’s patented FLAT shaped frequency response probes read out in Percent of RESPONSE Standard and are particularly useful in complex, multi-signal OR SHAPED environments where exposure limits are different for the various FREQUENCY emitter frequencies and in classified environments.

  • Page 12: Connecting A Probe

    The readout on the 8718B is shown in terms of Percent of Standard. The full scale of Narda’s shaped probes is typically either 300% or 600% of a standard. This permits measurements of exposure environments where the weighted field strengths...

  • Page 13: Correction Factors

    Probe Identification Narda 8700D series probes use the following labels and indicators: Field Type (E or H) Full Scale Measurement Range Model Number Standards (Shaped Probes Only) Frequency Range Serial Number Correction Factor Listed for Every Calibration Frequency Model Number and Serial Number •...

  • Page 14: Getting Started

    Making a Measurement Introduction This chapter will help you make measurements with your Model 8718B. Information is included for turning the meter on, selecting, zeroing, and testing a probe, plus an explanation of the main measurement screen of the meter. Some general...
  • Page 15 Narda's 8700 Series system is completely modular — all 8700 series meters work with all 8700 series probes. The single most important thing you must do is tell the 8718B meter which probe you are using. The single most im-...

  • Page 16: Table Of Contents

    To select from the PROBES IN MEMORY... Chapter 4 Making a Measurement 1. If you haven’t already, press F1 (MEASURE). 2. The model number and the serial number of the last probe used will be displayed on the second line of the display.

  • Page 17: S E L E C T P R O B E

    To use a PROBE that is NOT IN MEMORY... You must return to the Opening Menu Screen and repeat the probe selection and zeroing process if you want to change probes. Press 7 (Probe) from the First Menu Screen and then press F4 (RESTART).

  • Page 18: Y E S

    Zeroing the Probe The probe and meter must be “zeroed” together. It is important that the probe is not exposed to radiated fields during the zeroing process. The storage case is shielded and provides a convenient “zero density” environment. To zero the probe... Position the probe in the case with one test point pointed...
  • Page 19 See Chapter 12, Probe Zero, for additional infor- To reconfirm the zero while the instrument is in use... mation on the char- acteristics of the survey system including the causes of zero drift. Measurement Display Screens There are two display screen options: Main Measurement Display Screen The Main Measurement Display Screen shows a maximum value on the third line of the display.
  • Page 20 Main Measurement Display Screen (Shaped Probes) BAR GRAPH • Indicates approximate • 100 segment, three MAXIMUM VALUE • Indicates the 1 2 . 1 maximum value that 2 7 . 5 has occurred since you began making measurements or since resetting the maximum using F2 (MAXR) •...
  • Page 21 Percent of Standard, to an equivalent power density value at a particular frequency. Make sure that the 8718B is set to the correct exposure standard. See Chapter 11 Using the Standards Feature.
  • Page 22 Alternate Measurement Display Screen (Shaped Probes) BAR GRAPH • Indicates approximate • 100 segment, three 10:1 CALCULATED FIELD STRENGTH 1 2 . • Displays field strength 0 . 6 1 in mW/cm that has been calculated from the % STD reading using the referenced standard and the indicated frequency...
  • Page 23 Alternate values can- not be calculated at low frequencies for standards with very high magnetic field To return to the Main Measurements Display Screen... limits. A “greater than” symbol (>) is shown under these conditions. Change the units (if needed) by pressing either F1 (kHz), F2 (MHz), or F3 (GHz).

  • Page 24: Testing The Probe

    If you exceed the full scale measurement range of the probe, the word "OVERLOAD" will appear Testing the Probe Your Model 8718B is equipped with two RF sources for testing probes. Press Test Source and both sources will stay on for approximately 20 seconds.
  • Page 25 Multiplying the reading on the meter by a correction factor marked on the handle of a Narda 8700 Series probe compensates for the probe’s frequency sensitivity. The Model 8718B is unique because it can perform this task automatically. Correction factors can be used: •...
  • Page 26 Correction factors should NOT be used: Do not use correction factors in a broadband, To use a correction factor for a probe in memory... multi-emitter environ- ment. Chapter 4 Making a Measurement • When there are multiple emitters with frequencies that are close to each other and the nearest calibration frequencies have very similar correction factors.

  • Page 27: F1 F2 F3 F4

    To use a correction factor for a probe NOT in memory... Press F3 (MENU). The First Menu Screen will appear. D A T A L O G T I M E A V G S P A T I A L B A T / L I F E Press 8 (NEXT) to access the Second Menu Screen.

  • Page 28: The Probe

    Checking or Changing the Probe Model To check the probe model that the meter is currently set to... To change to another probe without turning the meter off... Measurement Uncertainty The uncertainty of any measurement includes several factors related to the probe and meter. Chapter 4 Making a Measurement Press F3 (MENU).

  • Page 29: Chapter 4 Making A Measurement

    The ellipse ratio is the ratio of readings that occur when one rotates the probe around the axis of its handle. Narda calibrates its probes by rotating the probe about its axis and using the mean value to determine the correction factor.

  • Page 30: Using The Menu System

    Using the Menu System General The menu system allows you to store data and to select various operating modes. It is accessed by pressing the appropriate function key that corresponds to MENU on the bottom line of the display screen. The menu is comprised of two menu screens and several sub-menus.
  • Page 31 Change the baud rate. Turn the RS232 port on or off. (Automatic RS232 on for Model 8718B. Menu is for Model 8718 only) Show the model and serial number of the probe in use. PROBE...

  • Page 32: Second Menu Screen

    Second Menu Screen Chapter 5 Using the Menu System C O R S E T T C A B L E / F O L O C K O U T Menu Enter a numeric probe correction factor. COR FACT Check or set the meter’s internal clock (time/date) Enter a value for temperature.

  • Page 33: Menu Commands

    Menu Commands The following is a list of menu commands that are shown on the fourth line of the display and selected by using the four function keys (F1-F4). AUTO ABORT BEGIN CABLE CANCEL CONT CLEAR DISCARD FREQ LEFT Auto – returns the meter to the normal, automatic temperature correction mode.
  • Page 34 MAIN MAXR MEASURE Measure – begin the measurement process by MENU PAUSE QUIT RESTART SAVE START STNDS STOP Chapter 5 Using the Menu System Main – switch to the Main Measurement Display Screen. Maximum Reset - reset the maximum value to the instantaneous value.
  • Page 35 Default Conditions Upon Turn-On The Model 8718B is designed to automatically return to a basic set of operating parameters every time it is turned on. Although in some cases this may require additional key strokes to set up the meter as desired, this feature is designed to minimize the chance of making measurements while unknowingly having the meter incorrectly configured.
  • Page 36 Time Averaging Unit of Measure Chapter 5 Using the Menu System Last Used unit of measure will be in use if previous and current probe both have flat or shaped frequency response. If current probe is shaped, unit will be % of STD.
  • Page 37 Operating the Meter...

  • Page 38: Available Units Of Measure

    Units of Measure Available Units of Measure The 8718B Meter allows you to quickly select any unit of measure that is appropriate for the probe in use. The available units of measure depend on whether the probe is designed to measure the electric field or the magnetic field.

  • Page 39: Changing The Unit Of Measure

    Changing the Unit of Measure To change the unit of measure that the meter is set for ... Access the menu system by pressing the function key that corresponds to the legend below MENU on the bottom line of the display. Press the number 5 on the keypad to select UNITS from the First Menu Screen.

  • Page 40: Understanding Spatial Averaging

    Spatially Averaged Measurements Understanding Spatial Averaging The major standards concerned with human exposure to radio frequency radiation specify maximum exposure levels averaged over the whole body. The co-linear dipole antenna arrays that are very common in modern wireless communications systems, for example, have multiple lobes close to the antenna.

  • Page 41: Spatial Averaging With The 8718B

    Spatial Averaging with the 8718B The Model 8718B uses time to quickly make precise, spatially averaged measurements. With the 8718B set for spatial averaging, press the F1 function key to start the timer. Pressing the same key again stops the timer. During this interval of time, the meter takes a large number of measurements.
  • Page 42 It is important to move the probe vertically at a con- stant rate to obtain an accurate spa- tially averaged measurement. The averaging time resolution is approxi- mately 1/4 second. Chapter 7 Spatially-Averaged Measurements Press F1 (START) while slowly moving the probe vertically at a constant rate of movement.
  • Page 43 10. To make another spatially averaged measurement, press F1 (START) again. 11. To temporarily suspend the spatial average mode and make real time measurements, press F2 (CLR). To make another spatially-averaged measurement, press F1 (START) again. 12. To end spatial averaging altogether, press F4 (QUIT). The meter will automatically return to the standard measurement screen.

  • Page 44: Data Logging

    The 8718B Meter features several methods of collecting data. The basic choices are: Logging Data The 8718B has three logging modes to collect field strength measurements, store the data in the meter’s memory, and later export the data to a personal computer via the RS232 port on the top of the meter.

  • Page 45: Format For Logged Data

    The header defines the serial number of the 8718B meter, its calibration date, the probe model used, and a number of other settings.
  • Page 46 To initiate one of the three logging modes described above... If you access the menu system from the Opening Menu Screen, you will re- turn to that screen. Once a probe has been selected and zeroed, the measure- ment screen will re- flect the logging mode that you have selected.

  • Page 47: Mode 1 Logging

    Mode 1 Logging To initiate Mode 1 logging (a series of data points with a reference number assigned to each data point)... Press the number 1 on the keypad to select LOG WITH REF # from the logging menu screen. A screen will appear requesting that you assign a two- digit survey number to this logging run of data points.
  • Page 48 Chapter 8 Data Logging A screen will appear that indicates the value of reading that has been temporarily stored in memory and the number of the data point. The first data point will be 001. D A T A P O I N T 1 2 .

  • Page 49: Mode 2 Logging

    Mode 2 Logging To initiate Mode 2 logging (a series of spatially-averaged data points with a reference number assigned to each data point)... 13. Use the numeric keypad to enter a new two-digit survey number and then press F1 (OK) or ENTER. Again, make note of this number so that you can later associate this survey number with the data points collected.
  • Page 50 It is important to move the probe vertically at a con- stant rate to obtain an accurate spa- tially averaged measurement. Chapter 8 Data Logging N E W L O G G I N G N E W E N T E C L R Press F4 (QUIT) or F3 (MENU) if you change your mind.
  • Page 51 1 2 . 2 7 . 5 M A X S T O P A screen will appear that indicates the average and maximum values of the reading that has been temporarily stored in memory and the number of the data point.

  • Page 52: Mode 3 Logging

    Mode 3 Logging To initiate Mode 3 logging (a series of data points automatically logged at specific intervals)... Chapter 8 Data Logging 15. To end this logging run and begin a new run, press F3 (END). The screen will appear that allows you to enter another two-digit survey number.
  • Page 53 A screen will appear requesting that you assign a two- digit survey number to this logging run of data points. Use the numeric keypad to enter the two-digit number and then press F1 (OK) or ENTER. Make note of this number so that you can later associate this survey number with the data points collected.
  • Page 54 Chapter 8 Data Logging To log for a specific interval of time, enter a two-digit number on the keypad. If you make a mistake entering a number, simply continue entering numbers until the correct value is displayed. Then press either F1 (SEC), F2 (MIN), or F3 (HRS) and the meter will automatically return to the measurement screen with new options available for the function keys.

  • Page 55: Memory Capacity

    To end logging altogether and return to the standard measurement screen... Memory Capacity To determine the remaining memory of the 8718B meter... 10. A screen will appear requesting that you assign another two digit survey number to the new logging run.
  • Page 56 Press F4 (QUIT) To download the current memory contents, you must connect the 8718B to a computer. See Chapter 18, User's Software. O R Y S E D...

  • Page 57: Analog Output

    Analog Output The 8718B Meter allows the user to output a DC voltage that is proportional to the instantaneous measured value. connected to a typical chart recorder, it will provide a continuous analog record of the measured field strength. See Chapter 17, Operation with a Data Recorder.

  • Page 58: Time-Averaged Measurements

    Time-Averaged Measurements Measurement Options The 8718B meter features two averaging modes: Mode 1 Mode 2 Making Time-Averaged Measurements To make time averaged measurements ... Chapter 9 Time-Averaged Measurements • Perform fixed-time averaging over any one of several specific time intervals.

  • Page 59: Mode 1 Averaging

    Mode 1 Averaging To initiate Mode 1 averaging (fixed time averaging over any one of several specific time intervals)... Press number 1 on the keypad to select FIXED TIME from the averaging menu screen. Selecting Mode 1 averaging will automatically shut off Mode 2 averaging if it is on.
  • Page 60 Chapter 9 Time-Averaged Measurements The meter will continue to make real-time measurements until you initiate making the time- averaged measurement. Determine where you want to make the averaged measurement and place or hold the probe in the desired position. For short intervals, it may be practical to hold the meter in one hand and the probe in the other.
  • Page 61 If you access the menu system from To temporarily pause during a time-averaged the Opening Menu measurement... Screen, you will re- turn to that screen. Once a probe has been selected and zeroed, the mea- surement screen will reflect the averaging mode that you have selected.
  • Page 62 The PAUSE feature can be useful when measuring the aver- To change the averaging interval... age value from cer- tain rotating radars. The effective mea- surement technique requires you to pause during the pe- riod of time when you are not in the beam of the radar.
  • Page 63 To set the meter for a specific frequency... Press F4 (FREQ) from the measurement screen. A new screen will appear to allow you to enter a frequency. F R E Q U E N C Y : C O R R E C T . F A C T O R : 1 .
  • Page 64 To initiate Mode 2 averaging (averaging to meet the requirements of a specific standard)... Chapter 9 Time-Averaged Measurements Make sure that the meter is set for the correct standard or change it if needed. See Chapter 11, Using the Standards Feature. Make sure the meter is set to the correct frequency for the measurement you are making.
  • Page 65 If you access the menu system from the Opening Menu Screen, you will re- turn to that screen. Once a probe has been selected and zeroed, the mea- surement screen will reflect the averaging mode that you have selected. The meter will continue to make real time measurements until you initiate making the time- averaged measurement.
  • Page 66 The PAUSE feature can be useful when measuring the aver- age value from cer- tain rotating radars. The effective mea- surement technique requires you to pause during the pe- riod of time when you are not in the beam of the radar. To temporarily pause during a time averaged Continue this tech- measurement...
  • Page 67 To change the frequency... To change the frequency (once the current measurement interval has been completed or stopped), press F2 (CLR) if the averaged value is displayed. Once the meter is displaying real time values, the frequency menu is accessed by pressing F3 (FREQ). Proceed as previously described to set the meter to a new frequency.

  • Page 68: Alarm Description

    Alarm Settings Alarm Description The Model 8718B Meter is equipped with an audible alarm that emits sound through a tiny hole on the bottom of the meter. The alarm sounds automatically whenever the field strength exceeds the measurement range of the probe or over ranges.

  • Page 69: Fixed Alarm

    Fixed Alarm If you change to an- other probe with a different full scale measurement range, the alarm threshold will also change. A setting that is often used with shaped fre- quency response probes is 50% of Standard. To set the alarm for one of the 8722 series probes, which have...

  • Page 70: Variable Tone Alarm

    Variable Tone Alarm The fixed and vari- able tone alarms op- erate independently of each other. The meter can be set to have both alarms off, either one of the alarms on, or both alarms on. If both alarms are turned on, the variable tone rate will vary with the field strength un-...
  • Page 71 Operating the Meter...

  • Page 72: Standards Feature

    Using The RF Exposure Standards Feature Application The Model 8718B Meter is always set to reference a particular safety standard, regulation, or guidance. The 8718B uses the referenced standard in two ways: Checking or Changing the Standard To determine which standard the 8718B is currently set to reference ...
  • Page 73 Controlled Environments and for Uncontrolled Envi- To change the standard or tier that the 8718B references... ronments. For standards with only a single tier... I E E E C 9 5 . 1 - 1 9 9 9...
  • Page 74 For standards with two or three tiers... Changing the level referenced on a multi-tier standard does NOT change the characteristics of a probe ie. a probe rated at 600% of oc- cupational limits al- ways yields an output in Percent of the Oc- cupational limits.
  • Page 75 Operating the Meter...

  • Page 76: Controlling The Back Light

    Back Light and Battery Status Application for Back Light The liquid crystal display (LCD) on the Model 8718B Meter provides high contrast in bright outdoor lite. However, LCD’s do not generate any light and can be difficult to read in low light conditions.

  • Page 77: Checking Battery Status

    The Model 8718B Meter uses a custom rechargeable battery. Under normal conditions, the battery provides about 20 hours of use before it must be recharged. The two features on the 8718B that significantly increase the current draw and therefore reduce the operating time are the back light and the RS232 serial port.
  • Page 78 This is because there is very little voltage difference over a broad range of charge levels. The battery status indicator on the 8718B is reasonably accurate when indicating charge levels of more than 80% or less than 20%. Unfortunately, indicated charge levels greater than 20% but less than 80% are only very rough estimates.
  • Page 79 Operating the Meter...

  • Page 80: Display Blanking

    Keypad Lockout and Description The Lockout feature disables the keypad to prevent inadvertent changes in operation. This feature can be useful while climbing and/or if the meter is left unattended during a long data logging session. The Blank feature both disables the keypad and blanks the display.
  • Page 81 Display Blanking and Keypad Lockout To both blank the display and lock the keypad... To both activate the display and unlock the keypad... Access the menu system by pressing the function key that corresponds to the legend below MENU on the bottom line of the display.

  • Page 82: Understanding The Zero Function

    RMS (Root Mean Squared) indications of field strength. Diode detectors, which are used in many of Narda’s electric field probes, are always operated in the square law region. Since the diodes are not operated in a saturated mode to insure accuracy in multi-signal conditions, the survey system must be “zeroed”.

  • Page 83: Checking For Zero Drift

    Many competitive diode sensor probes exhibit drift for another reason - reaction to infrared light on the diodes. Narda probes do not have this problem. Narda uses special diodes with an integral light shield, photographic paper inside the probe cover, and a combination anti-static shield and blackout coating on the inside of the probe cover.

  • Page 84: Establishing A Zero Field

    Temperature Concerns It is important to allow the meter and probe to become conditioned to the ambient temperature before attempting to zero the system. This is especially important when the meter and probe have been transported or stored at a different temperature such as in a vehicle, for example.

  • Page 85: Shielding The Probe

    The elastic band can easily be moved to use the 8718B’s built-in low frequency RF test source. Alternately, use an aluminum can.
  • Page 86 Zeroing the Probe While In Use The meter and probe are initially zeroed before the meter is allowed to go into the measurement mode. If you determine that significant drift may have occurred, it is simple to fine tune the zero.
  • Page 87 Operating the Meter...

  • Page 88: Advanced Settings

    Advanced Settings Description The Settings menu is used to control several features of the Model 8718B that need to be accessed infrequently. options available under the Settings menu are: Accessing the Settings Menu To access the Settings menu... Chapter 15 Advanced Settings •...

  • Page 89: Setting The Clock

    Setting the Clock To check and/or change the time and date... To set the time... Access the settings menu by following the procedure described in Accessing the Settings Menu. Press 1 to select CLOCK. A new screen will appear that displays the time on the left side of the screen and the date on the right.

  • Page 90: Temperature Correction

    If the two components are operating in different ambient temperature environments, the 8718B can be set to Chapter 15 Advanced Settings Proceed to setting the date, if required.
  • Page 91 correct for the temperature differential. The amount of error that can occur when the meter and probe are operating at different temperatures depends on the particular probe design as well as the temperature differential. The maximum error that can occur is about 1% per degree Centigrade for diode probes and about 0.1% per degree Centigrade for thermocouple probes.

  • Page 92: Clearing The Memory

    All data will be lost when the memory is cleared. To download the current memory contents prior to clearing the memory you must connect the 8718B to your computer. See All data will be lost Chapter 18, User's Software.
  • Page 93 This situation occurs during spatial averaging, data logging, and time averaging. The four function keys on the Model 8718B allow for easy operation with your thumb and the raised area around each key makes it easy to be certain that your thumb is in the correct location.

  • Page 94: Adjusting The Display Contrast

    Adjusting the Display Contrast The LCD display is set at the factory for the best contrast under typical conditions. The user can adjust the contrast to optimize visibility under specific lighting conditions. To adjust the display contrast... Chapter 15 Advanced Settings Press F1 (OK) to continue with the same setting without change.
  • Page 95 Press F4 (SET) to change the display contrast setting. The screen will change to show both the current setting and display an underscore where the new setting is entered. D I S P L A Y O L D S E T T N E W S E T T I N G : Use the numeric keypad to enter a single digit from 0-9...
  • Page 96 Description Narda fiber optic link transmitters are compatible with all 8700 series probes and the Model 8718B meter. The meter has a built-in fiber optic receiver compatible with the HP Versatile Link type plastic cables and connectors. The fiber optic transmitter connects directly or via a short cable to the probe.

  • Page 97: Controls And Indicators

    The fiber optic link system also allows the meter and probe to be separated by up to 50 meters. One application is surveying towers. A skilled climber carries the probe while the person actually making the measurements remains on the ground. Controls and Indicators The fiber optic transmitter has the following controls and indicators:...
  • Page 98 To set the meter to use the fiber optic receiver input... To set the meter to use the cable input... Chapter 16 Operation with a Fiber Optic Link Access the menu system by pressing the function key that corresponds to the legend below MENU on the bottom line of the display.

  • Page 99: System Checks

    Press F4 (CABLE) to change to the cable input. The meter will return to the First Menu Screen. Press Esc to return to the measurements screen. Set the 8718B to use the fiber optic receiver input as previously described. Connect the probe to the fiber optic transmitter.

  • Page 100: Output Level

    Operation with a Data Recorder Description The Model 8718B provides an output signal that can be connected to a data recorder to provide a continuous record of measurement over an extended period of time. The recorder output is available via the smaller of the two jacks located on the left side of the meter.
  • Page 101 The recorder output can be set to one of three fixed ranges by changing the bar graph range setting. See Bar Graph Ranges on page 23. The recorder output has an approximate 1/4 second RC time constant. Field Strength Recorder Voltage 0.01 mW/cm 0.03 volts 0.50 mW/cm...

  • Page 102: System Requirements

    User’s Software Description The 8718B User’s Software is a Windows™ - based program that performs three basic functions: The User’s Software for the Model 8718B is supplied on a compact disk. It should be permanently installed on the hard drive of a personal computer.
  • Page 103 Follow the instructions that appear on your screen. The setup program places all of the program files in a directory on your hard drive called 8718B. A new program group called RF Safety will be created. Click on Programs from the Start menu in Microsoft Windows.
  • Page 104 Main Menu Screen Chapter 18 User's Software...
  • Page 105 Viewing or Changing Probe Calibration Data The 8718B knows the basic parameters of all 8700 series probes i.e. frequency range, type of probe (electric or magnetic field), measurement range, and standard calibration frequencies. The term “installed”...
  • Page 106 The table in the top left hand corner lists the probes by model and serial number that have been installed in your Model 8718B. A small box just below the table lists the total number of installed probes.

  • Page 107: Installing A Probe

    Installing a Probe You may have a maximum of six probes installed in the 8718B at any time. If you have six probes installed and want to install another probe, you must first remove a probe. See Removing Installed Probes.
  • Page 108 Probe Installation Screen Chapter 18 User's Software...
  • Page 109 Removing Installed Probes To remove a specific probe from the meter’s memory... Enter any special calibration frequencies on the extra lines provided and enter the appropriate calibration factors. Delete any standard calibration frequencies that were not used. Click on the Install Probe button. A dialog box will appear asking you if you are sure you want to install the probe.

  • Page 110: File Format For Survey Data

    Establishing Communications... Select Download New Survey from the Survey Data menu. A dialog box will appear that reminds you to make sure that the 8718B is in a menu and not in a measurement mode.. Click OK.

  • Page 111: Selecting A File To View

    Three sample files were loaded on your hard drive when installed the User’s Software. There is a sample for each of the three modes of data logging. Selecting a File to View To view stored surveys on your computer... Logged Survey Data Window The Logged Survey Data window is comprised of two parts: 1) The header section at the top of the window defines the equipment that was used to make the survey.
  • Page 112 Logged Survey Data Screen Chapter 18 User's Software...
  • Page 113 2. The lower section of the window shows the measured data in both tabular and graphical form. If you used the PAUSE feature dur- ing continuous log- ging, the time shown for each data point will be incorrect for all data points after the pause feature was used.

  • Page 114: Printing A Logged Data Record

    To view another survey file... To return to the Main Menu Window... Printing a Logged Data Record To print a copy of the Logged Survey Data window that you are viewing... Chapter 18 User's Software The up and down keys to the right of Increment or Decrement By are used to determine how many records you advance or go back every time you click on the Prev.

  • Page 115: Exporting Data

    The default directory for exported survey files is Ssdata, which is a subdirectory under 8718B. You can select any drive and directory to export your file from this dialog box.
  • Page 116 Narda if you believe the meter is not functioning properly. Update Meter Firmware A powerful feature of the Model 8718B is the ability to update its operating software, or firmware, in the field. The password- protected Update Meter Firmware menu of the User’s Software is used to update the firmware.
  • Page 117 Enter the password obtained from Narda and click OK. Read the description of the three meter models. Click Yes to update a Model 8718B meter. Click No if your meter is a previously updated Model 8718 unit that currently has firmware version 3.0 or higher. Click Cancel if the meter is a Model 8718 that has a firmware version lower than 3.0.
  • Page 118 Communications with a Computer Application The Model 8718B can be connected to a computer for real time transmission of data via the meter’s RS232 connector. A limited number of the meter’s functions can also be controlled remotely via the RS232 bus.
  • Page 119 Command Characters >A000CSCR >C000CSCR >Dr00CSCR >E003XXXCSCR >F0r4XXXXCSCR >H000CSCR >P000CSCR >L000CSCR >V000CSCR >X000CSCR Command Characters Communications Protocol A) Ground Rules 1) CS= two digit checksum (2 ASCII (Hex) characters) NOTE: The ">" is NOT included in the checksum calculation 2) CR= one digit camage return (13 or $0D) 3) x= data 4) r= range 5) >=ASCII “>”...
  • Page 120 Command Characters II To Change or initiate the following: Auto Zero Read Clock Correction Factor Frequency Survey Data Read Field Response format 12 data bytes (6 data, 6 units) + CSCR. [Last displayed value (6 characters) + units of last displayed value (6 characters) exactly as displayed, except squared and cubed symbols.] Note: Superscript 2 or 3 are Hex 80 or Hex 81, respectively.
  • Page 121 Command Characters Display Averaging Read Calibrated Read Log Data Read Header SEND Read Max >X000CSCR ASCII >X000E8CR 3E 58 30 30 30 45 38 0D Reset Max >Y000CSCR ASCII >Y000E9CR 3E 59 30 30 30 45 39 0D >Dr00CSCR r=l for minimum to 4 for maximum display averaging Example: to set minimum display averaging (4:1) ASCII >D100D5CR...

  • Page 122: Theory Of Operation

    Preamplifiers U1 and U2 amplify the signals from the detectors and route them to the meter via connector P1. Model 8718B Meter Functional Description The meter receives the signal(s) from the probe, processes the signal(s) and provides a visual display of the levels detected.
  • Page 123 When in an operating mode and the probe is in a zero field, the operator presses the Auto Zero key to begin the auto zeroing routine. The 8718B meter uses a unique digital method to set the zero reference.
  • Page 124 Appendix B Theory of Operation...
  • Page 125 Calibration is performed using the RS-232 port, a voltage source and a computer. PCB A1 is the primary circuit board within the meter. The PCB A1 majority of the components are surface mount. It is located in a heavily shielded area beneath the keypad. Operating power from battery B1 is routed through Q3 and Q4 that form a momentary switch for the micro controller U5.

  • Page 126: Probe Designs

    7.2 Ah. The battery pack contains an over current protection device. It connects directly to PCB A1. Probe Designs The probes used with the Model 8718B meter measure either the electric field or the magnetic field. frequency response, others have a shaped frequency response (see Chapter 3, Probe Selection).
  • Page 127 The output from each set of detectors is processed Probes separately by separate amplifier circuits in the probe handle. The two signals are summed within the 8718B meter. Models include the Model 8741D that has a flat frequency response and the x8722D series that have shaped frequency response characteristics.
  • Page 128 This provides for the independence of probe orientation relative to the polarization of the field. distribution on adjacent cold junction elements produces a potential difference across the thin-film resistive thermocouples and a resultant dissipation of energy in these films. As the frequency increases, the phase difference between the potentials developed in adjacent junctions also increases the open circuit voltage.
  • Page 129 Appendices...

  • Page 130: Replacement Parts

    Do not use any type of detergent or solvent. Calibration The Model 8718B is calibrated before it is shipped. Narda recommends that the Model 8718B be calibrated every two years. Narda will perform this calibration for a nominal charge.
  • Page 131 Battery Charger, 230 volt Battery Charger and Line Cord Options The Model 8718B contains a rechargeable battery. The meter is supplied with either a 115-volt 50/60 Hz or a 230-volt 50/60 Hz charger. The 115-volt charger plugs directly into the style of wall outlets common to North America.
  • Page 132 This service is available to our customers at no charge. At the end of this product’s effective life cycle, it may be returned to Narda for proper disposal. Appendix C Maintenance...
  • Page 133 Appendices...
  • Page 134 Audio Alarm Alarm Description Controlling Alarm Function Fixed Alarm Variable Tone Alarm Back Light Bar Graph Battery Accuracy of Battery Status Indicator Battery Capacity Charger, description Charger, line cord options Checking Battery Status Rechargeable Management Program Clock Communications with Computer Correction Factors Data Logging Format for Logged Data...
  • Page 135 Establishing a Zero Field Shielding the Probe Temperature Concerns Understanding the Zero Function 81 Zeroing the Probe, in use Zeroing the Probe, initial Spatially-Averaged Measurements Spatial Averaging with the 8718B Understanding Spatial Averaging Standards Feature Time-Averaged Measurements Making Time-Averaged Measurements Measurement Options...
  • Page 136 Narda STS shall not be liable for any direct or consequential injury, loss or damage incurred through the use, or the inability to use, any Narda STS product.
  • Page 137 USA: 435 Moreland Road Hauppauge, NY 11788 Tel 1-631 231-1700 Fax 1-631 231-1711 E-Mail NardaSTS@L-3COM.com www.narda-sts.com GERMANY: Sandwiesenstrasse 7 D-72793 Pfullingen Tel +49-7121-9732-777 Fax +49-7121-9732-790 E-Mail support@narda-sts.de www.narda-sts.de...

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