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EMC Directive and Low Voltage Directive EN61010-1 (1993) Electrical Safety EN61326-1 (1997) EMC – Emissions and Immunity Manufacturer’s Name: Manufacturer’s Address Giga-tronics, Incorporated 4650 Norris Canyon Road San Ramon, California 94583 U.S.A. Type of Equipment: Model Series Number USB Power Sensor...
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Giga‐tronics GT‐8550A Series USB Power Sensors Record of Changes to This Manual Use the table below to maintain a permanent record of changes to this document. Corrected replacement pages are issued as Technical Publication Change Instructions (TCPI). When you are issued a TCPI, do the following: 1. Insert the TCPI at the front of the manual binder. 2. Remove the pages from the manual binder that are noted in the TCPI. 3. Replace the page(s) removed in the previous step with the corrected page(s). 4. Record the changes in the table below. TPCI Number TPCI Issue Date Date Entered Comments ...
Giga‐tronics GT‐8550A Series USB Power Sensors Safety and Manual Conventions 1 Safety and Manual Conventions This manual contains conventions regarding safety and equipment usage as described below. 1.1 Product Reference Throughout this manual, the term “GT‐8550A” refers to all models of power sensors within the GT‐8550A series, unless a specific model power sensor is referenced. 1.2 Personal Safety Alert WARNING: Indicates a hazardous situation which, if not avoided, could result in WARNING death or serious injury. 1.3 Equipment Safety Alert CAUTION: Indicates a situation which can damage or adversely affect the GT‐8550A or CAUTION associated equipment. 1.4 Notes Notes are denoted and used as follows: NOTE: Highlights or amplifies an essential operating or maintenance procedure, practice, condition or statement. Operation Manual, Part Number 34780, March 4, 2010 ...
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Safety and Manual Conventions Giga‐tronics GT‐8550A Series USB Power Sensors This page is intentionally blank. Page 2 Operation Manual, Part Number 34780, March 4, 2010 ...
Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2 Introduction 2.1 Overview NOTE: In this manual, the GT‐8550 Series USB Power Sensor is referred to generically as the “GT‐8550A” for simplicity. The specific model of power sensor is used where necessary. This manual provides information about the installation and operation of the GT‐8550A Series USB Power Sensors. Product description, specifications, and support are included. Changes to this manual are recorded in Record of Changes to This Manual in the front section. The GT‐8550A features a rugged body that connects directly to a desktop or laptop computer using a standard USB port and USB cable. A separate power meter is not required. The GT‐8550A Series USB Power Sensors allow for immediate conversion of RF and microwave power into digital data right at the point of power sensing. The companion application software, Measurement Xpress, provides a Graphical User Interface (GUI) to make power and other measurements. The benefits of using Measurement Xpress are: • Familiar Microsoft® Windows Interface • Easy to read numbers and bar graphs • Fast update rate allows real time circuit tuning • Internal zero and cal – the sensor powers up ready to make measurements If you wish to program the GT‐8550A for automated testing, a Dynamic Link Library (DLL) is included in the USB flash drive that ships with the GT‐8550A. Information for programming the GT‐8550A is found in the GT‐8550A Series USB Power Sensors Remote Operation and Programming Manual. Sensor zeroing and meter reference calibration are not required. This reduces setup time and simplifies programming. The GT‐8551A and GT‐8552A models feature triggering capabilities. (Refer to the Specifications chapter on page 51). ...
GT‐8550A Measurement Setup GT‐8550A Series USB Power Sensor USB cable RF input Computer with Measurement Xpress software installed 2.2 Sensors in the GT-8550A Series Table 1 below lists the basic parameters of the four models of power sensor in the GT‐8550A Series. Table 1 GT‐8550A Series Sensors: Basic Specifications and Applications Sensor Model Parameter GT‐8551A GT‐8552A GT‐8553A GT‐8888A Frequency 100 MHz to 8 GHz 100 MHz to 8 GHz 10 MHz to 18 GHz 10 MHz to 8 GHz ...
Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.3 Receiving and Inspection Upon arrival, inspect the contents of the GT‐8550A shipping container. The GT‐8550A consists of: • Sensor: there are four models of sensors to choose from. These are described in Table 1 on the previous page. • USB cable to connect the sensor to a computer (supplied with sensor) • USB flash drive containing: • Measurement Xpress software (this may also be downloaded from the website www.gigatronics.com) • Files to enable programming the GT‐8550A USB Series Power Sensor. 2.4 Computer Requirements for Measurement Xpress Software Table 2 below shows the requirements of the computer used with the GT‐8550A Series USB Power Sensors. Table 2 Computer Requirements for Measurement Xpress Software Parameter Specification Type of computer IBM‐compatible Operating system Microsoft® Windows XP or Windows Vista Processor speed > 500 MHz ...
Introduction Giga‐tronics GT‐8550A Series USB Power Sensors Measurement Modes This section explains the measurement modes listed in Table 1 on page 4. 2.4.2 Continuous Wave (CW) Use CW for measuring un‐modulated CW RF signals. 2.4.3 Burst Average Power (BAP) The Burst Average Power (BAP) mode measures the average power during an RF burst (See Figure 2). This mode is very useful for measurement of pulse modulated signals which are not flat or have amplitude modulation during the pulse ON period, as in the case of TDMA (Time Division Multiple Access) communications signals. In this mode, the GT‐8550A recognizes the beginning and end of a burst of RF power and takes an average of the power during that burst. The RF level can vary over a wide range during the burst as long as it remains above a noise threshold, which is automatically calculated by Measurement Xpress. As soon as the RF power drops below the noise threshold, the RF burst is complete and all further readings are discarded until the next burst starts. Figure 2. Burst Measurement In BAP mode, the GT‐8550A automatically determines which portions of the signal are in the pulse and which are not. In computing the average power, the GT‐8550A uses only those portions that are within the pulse. The result is that, independent of the signal’s pulse duty cycle, the meter always reads the average power in the pulse or burst. As with the PAP mode, when measuring a pulse modulated signal with 50% duty cycle, the reading in the BAP mode would be 3 dB higher than in the MAP mode. ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.4.4 Modulated Average Power (MAP) The Modulated Average Power (MAP) mode measures RF signals which are amplitude modulated, pulse modulated, or both. In the MAP mode the GT‐8550A calculates the average RF power received by the sensor over a period of time controlled by the time constant of the internal digital filter. The result is comparable to measurement by a thermal power sensor. In this mode, the 8550A measures the average power of CW and modulated signals, such as: • AM • Two‐tone • Multi‐carrier • Pulse modulation • Digital modulation (QPSK, QAM, etc...) For example, if an RF signal is pulse modulated at 50 Hz with a 10% duty cycle is measured with the averaging factor set to 128, the measured power reading will be 10% of the peak power during pulse ON periods. If the signal is modulated at a low pulse rate (below about 1 kHz), the GT‐8550A will synchronize the readings precisely with the start of a pulse so that each displayed reading is averaged over a whole number of pulses (there are no fractional pulses included in the measurement). This eliminates a significant amount of noise from the readings. However, even though the filter settling time has been set to a long time constant of 2.56 seconds, the update rate of the reading will be much faster; even the first reading will be very close to the fully settled value. 2.4.5 Pulse Average Power (PAP) The Pulse Average Power (PAP) mode is similar to the MAP mode, but it measures pulse‐modulated signals having a known duty cycle. Specify this duty cycle and the GT‐8550A will automatically correct the measurements so that the displayed readings indicate the peak RF power during pulse ON periods. For example, when measuring a pulse modulated signal with 50% duty cycle, MAP mode would give a reading 3 dB lower than the reading that would be given by PAP mode with the duty cycle factor set to 50%. NOTE: The duty cycle correction presumes a perfectly rectangular profile for the RF pulse shape. Any abnormality such as overshoot, undershoot, slow rise time or fall time, inaccuracy of the duty cycle, or deviation from a flat pulse response will cause errors in the indicated reading. ...
Introduction Giga‐tronics GT‐8550A Series USB Power Sensors 2.5 USB Considerations Under normal circumstances, the Universal Serial Bus (USB) provides adequate power for the sensor. However, when the application requires a longer cable (greater than 3 to 5 meters), an active or self‐ powered hub may be required. The sensor electronics are powered by the USB and typically draws 450 mA at a nominal 5 VDC. An active hub will compensate for the DC voltage drop beyond approximately 3 to 5 meters. An active hub is recommended when using a portable computer to conserve battery life, or when powering multiple sensors. The GT‐8550A Series USB Power Sensors are compliant with USB standard 2.0 and above. The following information is provided for reference when selecting a hub: USB Hub Considerations: • Bus‐powered hub: Draws a maximum of 100 mA at power up and 500 mA during normal operation. • Self‐powered hub: Draws a maximum of 100 mA and must supply 600 mA to each port. • Low power, bus‐powered functions: Draws a maximum of 100 mA (often applies to portable computers • High power, bus‐powered functions: Self‐powered hubs: draws a maximum of 100 mA and must supply 500 mA to each port • Suspended device: Draws a maximum of 0.5 mA. Page 8 Operation Manual, Part Number 34780, March 4, 2010 ...
Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.6 Install Measurement Xpress This section describes how to install the Measurement Xpress software on a computer. NOTE: Refer to Table 2 on page 5 for the requirements for the computer in which Measurement Xpress will be installed. Table 3 Install Measurement Xpress Step Action Connect the GT-8550A Flash Drive to a USB port on the computer. Locate and run MXsetup.exe on the GT-8550A Flash Drive. The first setup window is displayed (see Figure 3).
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Introduction Giga‐tronics GT‐8550A Series USB Power Sensors 2.7 Install Measurement Xpress, Continued Table 4 Install Measurement Xpress, Continued Step Action In the License Agreement window, read the license agreement, then click on “I accept the license agreement,” then click Next. Figure 4. Measurement Xpress Installation: License Agreement In the User Information window, fill in the user information fields, then click Next. Figure 5. Measurement Xpress Installation: User Information ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.7 Install Measurement Xpress, Continued Table 5 Install Measurement Xpress, Continued Step Action In the Destination Folder window, you can leave the destination folder set for the default, or use Browse to select another folder. When you have made your choice, click Next. Figure 6. Measurement Express Installation; Destination Folder In the Ready to Install window, click Next to proceed with the installation. Figure 7. Measurement Express Installation; Ready to Install ...
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Introduction Giga‐tronics GT‐8550A Series USB Power Sensors 2.7 Install Measurement Xpress, Continued Table 6 Install Measurement Xpress, Continued Step Action Measurement Xpress installs on your computer. Figure 8. Measurement Xpress Installation: Installation Begins The Successful Installation window appears when Measurement Xpress has completed its installation. Figure 9. Measurement Xpress: Installation Successful ...
Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.8 Install the GT-8550A USB Series Power Sensors ESD‐SENSITIVE DEVICE CAUTION Observe Electro‐Static Discharge precautions when handling the GT‐8550A Series USB Power Sensor: • Work at an ESD‐safe workstation • Keep the power sensor in an anti‐static bag when not using it. • Handle the power sensor with appropriate anti‐static clothing and wrist strap, or other discharge path. NOTE: Measurement Xpress software MUST be installed on the computer BEFORE the GT‐8550A Series USB Power Sensors are connected to the computer. After Measurement Xpress has been installed, there are two methods for configuring the computer for using the power sensors: • Automatic installation: Simply connect the USB power sensor to a USB port on the computer, and follow the prompts in the Hardware Wizard. To use this method, go to Table 7 below. • Manual installation: Installing the device manually is recommended only if your computer is unable to properly identify the correct driver. To use this method, go to Table 9 on page 14. Multiple Sensors: To install multiple sensors (up to 12), perform the installation procedure completely for each sensor. ...
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Select “Install from a list or specific location (Advanced)” and click Next to continue. In the following window, select “Don’t search, I will choose the driver to install,” then click Next. Select the Giga-tronics device as shown then click “Have Disk”. Select GTPM_855X.inf and click Open to continue. Select “Next” to continue the installation process as shown. When the installation completes, select “Finish” to close the Hardware Update Wizard.
Giga‐tronics GT‐8550 Series USB Power Sensors Introduction 2.9 Start Measurement Xpress Table 10 Start Measurement Xpress Step Action Connect a GT‐8550A sensor to a USB port on your computer. A green LED illuminates on the sensor, indicating that it is properly connected to the computer. Start Measurement Xpress. Figure 11 shows the initial Measurement Xpress window. The Connection Selection window opens every time you start Measurement Xpress. This window shows which (if any) USB power sensors are connected to the computer. In the Connection Selection window, click on OK to continue. Please be patient: This operation may require a few minutes depending on variables such as the PC configuration and number of sensors. Figure 11. Measurement Xpress Initial Display Continued next page Operation Manual, Part Number 34780, March 4, 2010 ...
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Introduction Giga‐tronics GT‐8550A Series USB Power Sensors 2.9 Start Measurement Xpress, Continued Table 11 Start Measurement Xpress, Continued Step Action The Connection Selection window disappears, and a Sensor window appears (see Figure 12). Figure 12. Measurement Xpress With Sensor Window If there are multiple sensors connected to the computer, you can open a window for each of them at any time. In the Navigation window, click on the sensor that you want to open (in this case, Sensor B). See Figure 13. NOTE: Figure 12 and Figure 13 shows Measurement Xpress with two sensors connected. In practice, there can but up to 12 sensors connected for Measurement Xpress. Figure 13. Open a Sensor Window ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3 Using Measurement Xpress 3.1 Overview This chapter describes in detail the Measurement Xpress Graphical User Interface (GUI). 3.2 Main Areas of the Measurement Xpress GUI Figure 14 below shows Measurement Xpress with two sensors connected to the computer. The main areas of the GUI are bordered in red. The next sections describe each of the main areas shown in Figure 14. Figure 14. Measurement Xpress GUI Menu Bar Measurement Display Sensor Windows ...
Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar This section describes in detail the menus in the Menu Bar. NOTE: Where a mouse click on a menu item leads to a selection, the symbol > is used. For example, clicking on File in the Menu Bar reveals the selection Exit. This is shown by: File > Exit. Table 12 Measurement Xpress Menu Bar Parameter Name Description File > Exit Closes Measurement Xpress View > Navigation Window Opens the Navigation Window (opens by default upon launch of Measurement Xpress). Or View > Message Window Opens the Message Window (opens by default upon launch of Measurement Xpress). Sensor > Sensor A Clicking on the Sensor menu item shows the sensors that are connected to the computer. Clicking on a selection opens that sensor window. Or Figure 15 show two sensor windows opened. Sensor > Sensor B Figure 15. Sensor Windows ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.3 Menu Bar, Continued Table 13 Measurement Xpress Menu Bar, Continued Parameter Name Description Sensor Operation > Sensor Setup/General tab: Setup Figure 16 shows the Sensor Setup window that opens when you select Setup. Figure 16. Sensor Setup Window, General Tab Tabs • Mode: selects the measurement mode. The model of GT‐8550A sensor determines the type of measurements you can make. The measurement mode choices are: • CW ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar, Continued Table 14 Measurement Xpress Menu Bar, Continued Parameter Name Description Sensor Operation > General tab (continued): refer to Figure 16 on page 19. • Setup Power Unit: selects the measurement unit that best suits your application. • Averages: use when measuring a CW signal that varies in power over time. Minimal averaging is 1, which averages the power measurement over approximately 0.5 ms. If the signal’s power variation is slower, a greater average number must be used. Generally, the correct Averaging setting can be found by starting with a small number, and increasing it until CW readings stabilize. • Duty Cycle: available only in PAP measurement mode (see section 2.4.5 on page 7). Enter the duty cycle of the signal to ensure accurate readings. • Alarm Power Limits (Upper and Lower): allows you to select power levels for activating the alarm. • Enable limits: activates the alarm according to the limits set in the previous item. • Frequency: sets the frequency of the measured signal. • Relative (Reset): Power Unit must be set to dB Relative to enable this function. Whenever you click on Relative (Reset), the power indication in the Sensor window updates to show the RF power at the moment the Reset button was clicked. This is useful if the power level of the signal is drifting. •...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.3 Menu Bar, Continued Table 15 Measurement Xpress Menu Bar, Continued Parameter Name Description Sensor Operation > Sensor Setup/Display Tab Setup The settings in this window determine the information displayed in the Sensor Windows. Figure 17 shows all of the settings in the Display tab selected, and Figure 18 shows the result of selecting all display options. Figure 17. Sensor Setup Window/Display Tab Figure 18. Sensor Window With All Display Options Selected Display options selected ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar, Continued Table 16 Measurement Xpress Menu Bar, Continued Parameter Name Description Sensor Operation > Sensor Setup/Display Tab, Continued Setup When CW mode is selected on the General tab, only Offset, Min Power, and Max Power is available as a selection. When any other measurement mode is selected, all of the following selections are available: • Offset: • Peak Power: • Avg Power: • Duty Cycle: • Crest Factor: • Min Power: • Max Power: Sensor Setup/Trigger Tab The settings in this window configure the external and internal triggers, and the recorder output. See Figure 19 below. Figure 19. Sensor Setup Window/Display Tab ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.3 Menu Bar, Continued Table 17 Measurement Xpress Menu Bar, Continued Parameter Name Description Sensor Operation > Sensor Setup/Trigger tab, Continued Setup External Trigger In: • Enable External Trigger: • Enable Falling Edge: • Timeout: Trigger Out: • Enable Trigger Output: • Enable Falling Edge: Internal Trigger: • Pulse Criteria Recorder Out Setup: • Enable recorder output • Power Unit • 0 V • 1 V Sensor Operation > Selecting Pulse Profiling opens the Pulse Profiling window (see Figure 20 below). ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar, Continued Table 18 Measurement Xpress Menu Bar, Continued Parameter Name Description System > Interface Selecting System/Interface (see Figure 21) opens the Connection Interface window (see Figure 22 below). Figure 21. Selecting System/Interface Figure 22. Connection Interface Window 3 1 Identifies the available sensors by model number. 2 ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.3 Menu Bar, Continued Table 19 Measurement Xpress Menu Bar, Continued Parameter Name Description System > General Info Selecting General Info from the System menu opens the General Information window (see Figure 23). Figure 23. General Information Window Information in this window includes: • Sensor letter assignments (A, B) • The model number of the GT‐8550A Power Sensor connected to the computer. • The serial number(s) of the GT‐8550A Power Sensors connected to the computer. • The address of the USB ports the GT‐8550A Power Sensors are connected to. • The version of the Giga‐tronics Dynamic Link Library (DLL) installed in ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar, Continued Table 20 Measurement Xpress Menu Bar, Continued Parameter Name Description Math > Math Setup Selecting Math > Math Setup (see Figure 24) from the Menu Bar opens the Math Setup window (see Figure 25). Figure 24. Selecting Math/Math Setup from the Menu Bar Figure 25. Math Setup Window This window allows you to apply basic math operations between two GT‐8550A Power Sensors, or between a sensor and a constant. The operations are: • Addition (+) • Subtraction (‐) ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.3 Menu Bar, Continued Table 21 Measurement Xpress Menu Bar, Continued Parameter Name Description Strip Chart > Selecting Strip Chart > Strip Chart Setup (see Figure 26) opens the Strip Chart Setup window (see Figure 27). Strip Chart Setup Figure 26. Selecting Strip Chart/Strip Chart Setup Figure 27. Strip Chart Setup Window The settings for this window are: • Sensors: Select which sensors to use for the strip chart. ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.3 Menu Bar, Continued Table 22 Measurement Xpress Menu Bar, Continued Parameter Name Description Strip Chart > Selecting Strip Chart > Strip Chart opens the Strip Chart window as shown in Figure 28. Notice the following: Strip Chart • Two sensors are shown, A and B, and they are color‐coded. • Sensor A is detecting a constant power source • Sensor B is detecting a source that is ramping in power approximately every 14 seconds. Figure 28. Strip Chart Window Windows Allows you to configure the layout of the Measurement Xpress GUI Help/About Displays information about the version of Measurement Xpress you are using. ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.4 Configure the GT-8550A USB Series Power Sensors Before any measurements are made in Measurement Xpress, the GT‐8550A Power Sensors must be configured. This section describes how to configure the power sensors. Table 23 Configure the GT‐8550A USB Series Power Sensors Step Action Install the GT‐8550A Power Sensors as described in section 2.8 on page 13. Start Measurement Xpress as described in section 2.9 on page 15. Open a sensor window for each sensor connected to the computer: On the Menu Bar, select Sensor > Sensor X (where X is any sensor that doesn’t have a sensor window opened). Figure 29. Opening Sensor Windows Repeat the previous step until all sensors connected to the computer have an open sensor window in the display area. Figure 30 shows sensor windows open for two sensors. NOTE: When you open Sensor Windows, you can drag and dock them to a convenient location, as shown in Figure 30. Figure 30. Two GT‐8550A Power Sensors Connected to the Computer ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.4 Configure the GT-8550A USB Series Power Sensors, Continued Table 24 Configure the GT‐8550A USB Series Power Sensors, Continued Step Action Click on a Sensor Window to select that sensor for configuration. On the Menu Bar, select Sensor Operation > Setup (see Figure 31). Figure 31. Select Sensor Operation/Setup The Sensor Setup window appears (see Figure 32). Figure 32. Sensor Setup Window Tabs ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.4 Configure the GT-8550A USB Series Power Sensors, Continued Table 25 Configure the GT‐8550A USB Series Power Sensors, Continued Step Action Configure the Sensor Setup window according to your testing needs. Complete information on configuring the Sensor Setup Window is available starting on page 19. When you have finished configuring the sensor, click on Apply&Close to apply the settings to the sensor. If you want to configure other sensors, repeat these instructions, starting at Step 5. End of Procedure Operation Manual, Part Number 34780, March 4, 2010 Page 31 ...
Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.5 Measure CW Power This section describes how to use Measurement Xpress to make CW power measurements. Table 26 Measure CW Power Step Action If necessary, do the following: • Connect the GT‐8550A USB Power Sensors to the computer (see section 2.8 on page 13). • Configure the sensors (see section 3.4 on page 29). DO NOT APPLY EXCESSIVE POWER TO THE GT‐8550A USB POWER SENSORS. • Read the specifications for the power sensor (see Table 1 on page 4) CAUTION • Know the approximate power level of the signal of interest before applying it to the GT‐8550A. Before connecting the RF signal to the GT‐8550A Power Sensor, de‐energize (turn OFF) the RF signal. Connect the GT‐8550A Power Sensor to the RF source. There are different ways to measure CW power. Choose among the following: • To determine RF power: use the Sensor window (see Figure 15 on page 18) • If you want to view a CW source that is changing over time: use the Strip Chart (see page 27). End of Procedure Page 32 Operation Manual, Part Number 34780, March 4, 2010 ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.6 Measure Pulse Power Measurement Xpress makes it possible to measure and view different aspects of pulse power. We recommend that you review the different pulse‐power measuring methods offered by Measurement Xpress in section 0 starting on page 6. Table 27 Measure Pulse Power Step Action If necessary, do the following: • Connect the GT‐8550A USB Power Sensors to the computer (see section 2.8 on page 13). • Configure the sensors for making pulse measurements according to your test needs (see section 3.4 on page 29). DO NOT APPLY EXCESSIVE POWER TO THE GT‐8550A USB POWER SENSORS. • Read the specifications for the power sensor (see Table 1 on page 4) CAUTION • Know the approximate power level of the signal of interest before applying it to the GT‐8550A. Before connecting the RF signal to the GT‐8550A Power Sensor, de‐energize (turn OFF) the RF signal. Connect the GT‐8550A Power Sensor to the RF source. Energize the RF signal. Figure 33 shows the Sensor A window under the following conditions: • Sensor type: GT‐8551A USB Power Sensor • RF input: square wave; pulse period, 80 us; pulse width, 40 us; power, 1 dBm •...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.6 Measure Pulse Power, Continued Table 28 Measure Pulse Power Step Action Figure 34 uses Pulse Profiling to display the same signal shown in Figure 33 on the previous page. Note the use of markers and a gate. Figure 34 includes blow‐ups of the Marker Status and Gate Status panes. 1 Figure 34. Pulse Profiling 2 2 ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.7 Use the Math Functions This procedure describes how to use the math functions of Measurement Xpress. The math functions enable you to add, subtract, or divide the outputs of two sensors, or of one sensor to a settable constant. To demonstrate the Math functions, we will connect a 1 dBm, 1 GHz CW signal to a GT‐8551A Power Sensor. Table 29 Use the Math Functions Step Action If necessary, do the following: • Connect the GT‐8550A Power Sensor to the computer (see section 2.8 on page 13). • Configure the sensors for making CW measurements (see section 3.4 on page 29). DO NOT APPLY EXCESSIVE POWER TO THE GT‐8550A USB POWER SENSORS. • Read the specifications for the power sensor (see Table 1 on page 4) CAUTION • Know the approximate power level of the signal of interest before applying it to the GT‐8550A. Setup Measurement Xpress to display sensor windows for both USB power sensors. See Figure 35. Figure 35. Measurement Xpress With Two Power Sensors ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.7 Use the Math Functions, Continued Table 30 Use the Math Functions, Continued Step Action On the Menu bar, click on Math > Math Setup (see Figure 36). Figure 36. Select Math Setup Math Setup The Math Setup window opens (see Figure 37). In this window: • Select the relationship between the sensors. • In the middle field in the window, click the down arrow ( V ) to select the math function you require ( /, +, or – ). • Click on Apply&Close. Figure 37. Math Setup Window Math functions ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.7 Use the Math Functions Table 31 Use the Math Functions, Continued Step Action The Math Setup window closes, and the Math Status window opens (see Figure 38). Notice that the Math Status window constantly updates the resultant value as the individual sensor outputs change. Figure 38. Math Status Window Math Status You can close the Math Status window anytime by clicking on the in the upper right‐hand corner of the window. End of Procedure ...
Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.8 Use the Strip Chart Function This section describes how to use the Strip Chart function of Measurement Xpress. Table 32 Use the Strip Chart Function Step Action Configure the power sensors according to your application. Figure 39 below shows Measurement Xpress configured to display two sensors. Figure 39. Measurement Xpress Configured to Display Two Power Sensors On the Menu bar, click on Strip Chart > Strip Chart Setup (see Figure 40). Figure 40. Strip Chart Setup ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.8 Use the Strip Chart Function, Continued Table 33 Use the Strip Chart Function, Continued Step Action The Strip Chart Setup dialog box opens. Configure the strip chart (see Figure 41): • Select which sensor(s) the strip chart will record. • Select the Sample Rate • Select the Duration • Name and save the file for the strip chart file. There are no name or location restrictions on naming and saving these files. • NOTE: The Strip Chart saves the information as a Comma Separated Values (CSV) file, which can be opened in Microsoft Excel. Figure 41. Strip Chart Setup ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.8 Use the Strip Chart Function, Continued Table 34 Use the Strip Chart Function, Continued Step Action The strip chart window opens. Click on Start to begin recording on the strip chart (see Figure 42). Note the following about Figure 42: • Both power sensors are shown, and each is color‐coded: Sensor A is blue, and Sensor B is pink. Figure 42. The Strip Chart Window Press Start When you clicked on Start in the Strip Chart window, Start changed to Stop. Press Stop anytime to stop the strip chart. End of Procedure ...
Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.9 The Pulse Profiling Window This section describes the parameters you can set and view in the Pulse Profiling window (see Figure 43 below). To open the Pulse Profiling window, you must use a GT‐8552A USB Power Sensor. When the GT‐8552A is connected to the computer, and its sensor window is open and selected, the Pulse Profiling function is enabled both in the Menu Bar, and in the Navigation Window (Sensor Operation/Pulse Profiling). Click on either of these to open the Pulse Profiling window. The settings and features available for the Pulse Profiling are described on the following pages. Figure 43. Pulse Profiling Window Marker status Gate status Sweep display Settings ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.9 The Pulse Profiling Window, Continued Table 35 The Pulse Profiling Window Parameter Description Settings: Sweep time Allows you to enter the duration of a sweep. Start/Stop Starts and stops the sweep. This is a toggled selection; clicking on it changes it to the opposite state. Single Starts a single sweep. Reset Removes all markers and gates from the display. Marker Clicking on this button allows you to place up to ten markers on the display. When you click on the Marker button, its color changes to red. You can then place markers anywhere on the display. Note that the markers are color‐coded. NOTE: to delete markers (see Figure 44): • To delete all markers, click on Reset in Settings. • To delete individual markers, select a marker in the Marker Status area, then right‐click on the selection to display more options, and left‐click on Delete MarkerX. Figure 44. Deleting Markers ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.9 The Pulse Profiling Window, Continued Table 36 The Pulse Profiling Window, Continued Parameter Description Settings: Marker Marker information: For each marker placed on the sweep display, a line of information appears in the Marker status pane. The information for each marker (continued) is updated regularly (see Figure 45). Figure 45. Marker Status Pane Marker 1 information Enable delta between markers: To view the difference (delta) between markers (see Figure 46): 1. Click on one of the markers in the Marker Status pane. 2. Right‐click on the selected marker to open the options pane. 3. Select one of the delta options. Figure 46. Turning On Delta Between Markers ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.9 The Pulse Profiling Window, Continued Table 37 The Pulse Profiling Window, Continued Parameter Description Settings: Marker All peak settings: To apply a peak setting to a marker, first select the marker you want to apply the peak setting to as shown in Figure 47. (continued) Figure 47. Selecting a Marker for Peak Setting 1) Click on the arrow to display the drop‐down list of markers; 2) Then select a marker. ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.9 The Pulse Profiling Window, Continued Table 38 The Pulse Profiling Window, Continued Parameter Description Settings: Gate Clicking on Gate enables you to place up to six gates anywhere on the sweep display. Figure 48 shows two gates on the sweep display. To place gates: 1. Click on the Gate button in the Navigation Window (the Gate button turns red). 2. Mouse‐click at those points on the sweep display where you want to place a gate. To adjust the width of a gate NOTE: In order to view information within a gate, you must adjust its width after placing it, as follows: 1. Click and hold on one of the vertical lines of the gate, and drag it to the desired point on the sweep display. Do the same action on the other vertical line of the gate. 2. Perform Step 1 on the other gates if desired. Figure 48. Gates Gate 2 ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.9 The Pulse Profiling Window, Continued Table 39 The Pulse Profiling Window, Continued Parameter Description Settings: Gate Gate information: After adjusting the width of a gate, you can view the gate’s information in the Gate Status pane (see Figure 49). Figure 49. Gate Status Pane Gate Status Pane Gates Continued next page ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.9 The Pulse Profiling Window, Continued Table 40 The Pulse Profiling Window, Continued Parameter Description Settings: Zoom In/Out gives you the ability to magnify areas of interest of the sweep in Pulse Profiling. Zoom In/Out To zoom in on a point: + 1 Click on under Zoom In/Out (see Figure 50). Note that the turns red. 2 Place the mouse cursor on the sweep display where you want the magnification to be centered (the red circle was added to the figure to show the cursor placement; it doesn’t appear in the application). 3 Click on the chosen point on the sweep display until you achieve the — desired level of magnification (see Figure 51). Use Zoom Out ( ) to fine‐ tune the display. Figure 50. Clicking on ...
Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.10 Use Pulse Profiling The Pulse Profiling function is a powerful feature of Measurement Xpress. Pulse Profiling allows you to see and measure many aspects of pulse waveforms. The following procedure describes how to use the Pulse Profiling function. NOTE: To enable Pulse Profiling, you must use a GT‐8552A USB sensor. Table 41 Measurement Xpress: Use Pulse Profiling Step Action You must use a GT‐8552A USB Power Sensor to enable Pulse Profiling. Connect a GT‐8552A to a USB port on the computer. Start Measurement Xpress. DO NOT APPLY EXCESSIVE POWER TO THE GT‐8552A USB POWER SENSOR. • CAUTION Read the specifications for the power sensor (see Table 1 on page 4) • Know the approximate power level of the signal of interest before applying it to the GT‐8552A. Connect the signal of interest to the RF connector on the end of the GT‐8552A power sensor. If there is more than one GT‐8550A Power Sensor connected to the computer, select the GT‐8552A in order to enable Pulse Profiling. Configure the measurement settings by opening the Sensor Setup Window: 1. In the Navigation pane, click on Setup (under Sensor Operation). 2. Configure the settings in the Sensor Setup window as desired. 3. Close the Sensor Setup window. In the Navigation Window, click on Pulse Profiling to open the Pulse Profiling window (see Figure 52). Figure 52.
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Giga‐tronics GT‐8550 Series USB Power Sensors Using Measurement Xpress 3.10 Use Pulse Profiling, Continued Table 42 Measurement Xpress: Use Pulse Profiling, Continued Step Action The Pulse Profiling window opens (see Figure 53). To view pulses, click on Start in the Pulse Profiling window. Figure 53. Pulse Profiling Window (before Start is clicked) Start button When you click on the Start button, you can view pulses (see Figure 54.) Notice that the Start button changes to the Stop button. This button toggles states whenever it is clicked. Figure 54. ...
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Using Measurement Xpress Giga‐tronics GT‐8550A Series USB Power Sensors 3.10 Use Pulse Profiling, Continued Table 43 Measurement Xpress: Use Pulse Profiling, Continued Step Action If necessary, adjust the Sweep Time to get a better view of the pulses of interest. Sweep Time adjustment You can now place markers and gates to obtain the information you desire from the sweep display. Refer to section 3.9 starting on page 41 for details on placing and using markers and gates. Figure 55 shows a sweep with two markers and two gates, and their data shown in the Marker Status and Gate Status panes. Figure 55. Markers and Gates on the Pulse Profiling Window ...
Giga‐tronics GT‐8550 Series USB Power Sensors Specifications 4 Specifications 4.1 General Specifications for all Sensors Table 44 General Sensor Specifications Parameter Specification USB voltage +4.5 V to +5.5 V USB power 450 mA typical, 500 mA maximum Operating temperature 0 °C to 50 °C Storage temperature ‐20 °C to +75 °C USB cable length 15 ft. (5 m) maximum Dimensions (10 GHz) 2” H x 2.5” W x 3” D (50 mm H x 65 mm W x 75 mm D) Dimensions (18, 26.5 GHz) 2” H x 2.5” W x 3.5” D (50 mm H x 65 mm W x 90 mm D) Weight < 1 lbs (< 0.5 kg) Environmental MIL‐PRF‐28800F, Class 3 WEEE compliant, RoHS compliant Safety EN 61010 and CE compliant Emissions EN 61326 and FCC compliant Video bandwidth GT‐8551A: ...
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Specifications Giga‐tronics GT‐8550A Series USB Power Sensors Table 45 General Sensor Specifications, Continued Parameter Specification Dynamic range GT‐8551A 100 MHz to 6 GHz: 6 GHz to 8 GHz: ‐60 dBm to +20 dBm ‐50 dBm to +20 dBm GT‐8552A 100 MHz to 6 GHz: 6 GHz to 8 GHz: ‐60 dBm to +20 dBm ‐50 dBm to +20 dBm GT‐8553A ‐50 dBm to +20 dBm GT‐8888A 10 MHz to 6 GHz: 6 GHz to 8 GHz: ‐60 dBm to +20 dBm ‐50 dBm to +20 dBm Maximum peak power +23 dBm (200 mW) (damage level) VSWR GT‐8551A 100 MHz to 250 MHz: 250 MHz to 8 GHz: 8 GHz to 10 GHz: 1.18:1 typical 1.18:1 1.15:1 GT‐8552A 100 MHz to 250 MHz: 250 MHz to 8 GHz: 8 GHz to 10 GHz: ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Specifications Table 46 General Sensor Measurement Capabilities Parameter Measurement Capability Strip Chart Mode Multiple Sensor, Adjustable Rate and Duration, and Data Logging Output File (CSV) Statistical Chart Mode Adjustable Rate, Duration, Range and Resolution, Histogram, CDF and CCDF Math Functions Ratio, Sum and Difference between sensors or between sensors and a constant Other Capabilities Selectable Power Units, Relative Function, Offset Function, Adjustable Averaging, Upper and Lower Alarm Limits, and Min and Max Hold Operation Manual, Part Number 34780, March 4, 2010 Page 53 ...
Specifications Giga‐tronics GT‐8550A Series USB Power Sensors 4.2 Sensor Measurement Uncertainty Factors 4.2.1 Accuracy Measurement uncertainty is computed from the individual cal factor, mismatch, linearity, noise and temperature error factors, and can be computed as either worst case (sum of the applicable error terms) or RSS, representing the most probable error, where RSS is the square root of the sum of the squares of the error terms. Accuracy is typically < 2 % (RSS) mid‐band with source VSWR 1.2:1 (or better) at 25 °C +/‐ 5 °C. This section presents correction factors for various aspects of sensor measurements. Table 47 GT‐8551A Measurement Uncertainty Factors Parameter Specification Calibration Factor 100 MHz to 0.5 GHz 0.5 GHz to 8 GHz ‐60 to +20 dBm 4 % 1.7 % Linearity 100 MHz to 2 GHz 2 GHz to 8 GHz +15 to +20 dBm 7 % 5 % +10 to +15 dBm 5 % 3 % ‐60 to +10 dBm 3 % ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Specifications 4.2 Sensor Measurement Uncertainty Factors, Continued Table 48 GT‐8552A Measurement Uncertainty Factors Parameter Specification Calibration Factor 100 MHz to 0.5 GHz 0.5 GHz to 8 GHz ‐60 to +20 dBm 4 % 1.7 % Linearity 100 MHz to 2 GHz 2 GHz to 8 GHz +15 to +20 dBm 7 % 5 % +10 to +15 dBm 5 % 3 % ‐60 to +10 dBm 3 % 2 % Noise 100 MHz to 6 GHz 6 GHz to 8 GHz ‐30 to +20 dBm 0.02 % 0.04 % ‐50 to ‐30 dBm 0.04 % 0.15 % ...
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Specifications Giga‐tronics GT‐8550A Series USB Power Sensors 4.2 Sensor Measurement Uncertainty Factors, Continued Table 49 GT‐8553A Measurement Uncertainty Factors Parameter Specification Calibration Factor 10 MHz to 1.0 GHz 1 GHz to 10 GHz 10 GHz to 18 GHz ‐50 to +20 dBm 1.8 % 1.7 % 1.9 % Linearity 10 MHz to 18 GHz +15 to +20 dBm 3 % ‐15 to +15 dBm 2.5 % ‐50 to +‐15 dBm 2 % Noise 10 MHz to 18 GHz ‐30 to +20 dBm 0.1 % ‐40 to ‐30 dBm 0.25 % ‐50 to ‐40 dBm 0.5 % Temperature 0 °C to 10 °C ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Specifications 4.2 Sensor Measurement Uncertainty Factors, Continued Table 50 GT‐8888A Measurement Uncertainty Factors Parameter Specification Calibration Factor 10 MHz to 0.1 GHz 0.1 GHz to 0.5 GHz 0.5 GHz to 8 GHz ‐60 to +20 dBm 7 % 4 % 1.7 % Linearity 10 MHz to 2 GHz 2 GHz to 8 GHz +15 to +20 dBm 7 % 5 % +10 to +15 dBm 5 % 3 % ‐60 to +10 dBm 3 % 2 % Noise 10 MHz to 0.1 GHz 0.1 GHz to 6 GHz 6 GHz to 8 GHz ‐30 to +20 dBm 0.22 % 0.02 % ...
Specifications Giga‐tronics GT‐8550A Series USB Power Sensors 4.3 Additional Technical Specifications Table 51 GT‐8551A Additional Measurement Capabilities Parameter Measurement Capability BAP Mode Pulse Power, Peak Power, Average Power, Duty Cycle and Crest Factor MAP Mode Peak Power, Average Power, Duty Cycle and Crest Factor PAP Mode Duty Cycle Corrected Power, Peak Power, Average Power and Crest Factor Table 52 GT‐8552A Additional Technical Specifications Parameter Specification Sample Rate 48 MS/s Rise/Fall Time < 55 ns (10% to 90%) at 4 GHz Minimum Pulse Width 100 nS typical Minimum Duty Cycle 0.01% Note 1: The minimum pulse width is the recommended minimum pulse width viewable on the power meter, where power measurements are meaningful and accurate, but not warranted. Note 2: The minimum duty cycle is the recommended minimum duty cycle viewable on the power meter, where power measurements are meaningful and accurate, but not warranted. ...
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Giga‐tronics GT‐8550 Series USB Power Sensors Specifications Operation Manual, Part Number 34780, March 4, 2010 Page 59 ...
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Specifications Giga‐tronics GT‐8550A Series USB Power Sensors End of Document Page 60 Operation Manual, Part Number 34780, March 4, 2010 ...
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