Agilent Technologies E7402A Tracking Generator Unleveled Condition, Measuring Device Bandwidth

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Making Complex Measurements

Making Stimulus Response Measurements

Tracking Generator Unleveled Condition

When using the tracking generator, the message TG unleveled may appear. The TG unleveled message indicates that the tracking generator source power (Source, Amplitude) could not be maintained at the selected level during some portion of the sweep. If the unleveled condition exists at the beginning of the sweep, the message will be displayed immediately. If the unleveled condition occurs after the sweep begins, the message will be displayed after the sweep is completed. A momentary unleveled condition may not be detected when the sweep time is short. The message will be cleared after a sweep is completed with no unleveled conditions.

The unleveled condition may be caused by any of the following:

•Start frequency is too low or the stop frequency is too high. The unleveled condition is likely to occur if the true frequency range exceeds the tracking generator frequency specification (especially the low frequency specification).

•Source attenuation may be set incorrectly (select Attenuation (Auto) for optimum setting).

•The source power may be set too high or too low, use Amplitude (Off) then Amplitude (On) to reset it.

•The source power sweep may be set too high, resulting in an unleveled condition at the end of the sweep. Use Power Sweep (Off) then Power Sweep (On) to decrease the amplitude.

•Reverse RF power from the device under test detected by the tracking generator ALC (automatic level control) system.

Measuring Device Bandwidth

It is often necessary to measure device bandwidth, such as when testing a bandpass filter. There is a key in the Peak Search menu that will perform this function. The device signal being measured must be displayed before activating the measurement. The span must include the full response.

Activate the measurement by toggling the N dB Points key to On. The analyzer places arrow markers at the − 3 dB points on either side of the response and reads the bandwidth. For other bandwidth responses enter the number of dB down desired, from − 1 dB to − 80 dB.

No other signal can appear on the display within N dB of the highest signal. The measured signal cannot have more than one peak that is greater than or equal to N dB. A signal must have a peak greater than the currently defined peak excursion to be identified. The default value for the peak excursion is 6 dB.

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Contents Signal Analysis Measurement Guide Safety Information Warranty Limitation of Warranty Contents Demodulating and Listening to an AM Signal Making Basic Measurements What is in This Chapter Test Equipment Specifications Recommended Model Test EquipmentComparing Signals Signal Comparison ExamplePlacing a Marker on the 10 MHz Signal Using the Marker Delta Function Frequency and Amplitude Difference Between Signals Resolving Signals of Equal Amplitude Resolving Signals Example Press SPAN, 2, MHz to bring the signal to center screenUnresolved Signals of Equal Amplitude Or linked to the center frequency Resolving Small Signals Hidden by Large Set one source to 300 MHz at − 10 dBm 10 Signal Resolution with a 10 kHz Resolution Bandwidth 12 Signal Resolution with a 30 kHz Resolution Bandwidth Making Better Frequency Measurements Better Frequency Measurement Example13 Using Marker Counter Decreasing the Frequency Span Around the Signal Decreasing the Frequency Span Example14 Detected Signal 16 After Zooming In on the Signal Tracking Drifting Signals Tracking Signal Drift Example17 Signal With Default Span 19 Signal With 500 kHz Span 21 Using Signal Tracking to Track a Drifting Signal 22 Signal With Default Span 24 Signal With 500 KHz Span 25 Viewing a Drifting Signal With Max Hold and Clear Write Measuring Low Level Signals Measuring Low Level Signals Example26 Low-Level Signal 28 Using 0 dB Attenuation 29 Decreasing Resolution Bandwidth 30 30 kHz Video Bandwidth 31 Decreasing Video Bandwidth 32 Without Video Averaging 33 Using the Video Averaging Function Distortion from the Analyzer Identifying Distortion ProductsIdentifying Analyzer Generated Distortion Example 34 Harmonic Distortion 36 RF Attenuation of 10 dB Third-Order Intermodulation Distortion Identifying TOI Distortion Example38 Third-Order Intermodulation Equipment Setup 39 Measuring the Distortion Product 40 Measuring the Distortion Product Measuring Signal-to-Noise Signal-to-Noise Measurement Example= 70 dB/Hz + 10 × log 30 kHz = -25.23 dB ⁄ 30 kHz Making Noise Measurements Noise Measurement Example42 Setting the Attenuation 43 Activating the Noise Marker 45 Increased Resolution Bandwidth 46 Noise Marker in Signal Skirt MHz 48 Viewing Power Between Markers 49 Measuring the Power in the Span Demodulating an AM Signal Example 50 Viewing an AM Signal 51 Measuring Modulation In Zero Span 52 Measuring Modulation In Zero Span 54 Measuring Time Parameters 55 Continuous Demodulation of an AM Signal Demodulating FM Signals Demodulating a FM Signal Example56 Establishing the Offset Point 57 Determining the Offset Demodulate the FM Signal 58 Demodulating a Broadcast Signal Making Complex Measurements What’s in This Chapter Required Test EquipmentUsing An Analyzer With a Tracking Generator Making Stimulus Response MeasurementsWhat Are Stimulus Response Measurements? Stepping Through a Transmission MeasurementTransmission Measurement Test Setup Tracking Generator Output Power Activated Decrease the Resolution Bandwidth to Improve Sensitivity Measure the Rejection Range Tracking Generator Unleveled Condition Measuring Device BandwidthExample DB Bandwidth Measurement at -3 dB Measuring Stop Band Attenuation Using Log Sweep N dB Bandwidth Measurement at -60 dBScale Type Log Tracking Generator Output Power Activated in Log Sweep 10 Normalized Trace After Reconnecting DUT 12 Minimum Stop Band Attenuation Making a Reflection Calibration Measurement ExampleReflection Calibration Measuring the Return Loss 14 Short Circuit NormalizedVswr Demodulating and Listening to an AM Signal Demodulating and Listening to an AM Signal ExampleNext Pk Right, or Next Pk Left Sweep Time, 5, s 17 Continuous Demodulation of an AM Signal Demodulating and Listening to an AM Signal

E7402A, E7405A, E7404A, E7401A, E7403A specifications

Agilent Technologies, a leader in test and measurement solutions, offers a range of spectrum analyzers designed to meet the evolving demands of the electronics industry. The E7403A, E7401A, E7404A, E7405A, and E7402A are prominent models that embody advanced features and technologies, enhancing performance, accuracy, and user experience.

The E7403A is recognized for its high-quality performance and wide frequency range. This model offers frequency coverage from 9 kHz to 3 GHz, making it suitable for both commercial and academic research applications. With a phase noise of -100 dBc/Hz at 10 kHz offset, it delivers exceptional sensitivity. The E7403A also features a built-in tracking generator, facilitating effective signal generation for testing.

Next in line, the E7401A provides similar frequency coverage but is optimized for portable functionality. Weighing significantly less than its counterparts, it is easy to transport, making it ideal for field applications. Users benefit from its fast sweep speed of up to 3 GHz, which is crucial in quickly identifying and analyzing signals.

The E7404A excels in its comprehensive analysis capabilities. With a frequency range extending up to 6 GHz, it supports more demanding applications, including wireless communications and satellite technology. Its advanced digital signal processing capabilities enable the analysis of complex modulated signals, providing engineers with the data needed to troubleshoot and optimize system performance.

The E7405A is a highly versatile model that offers frequency coverage from 9 kHz to 20 GHz. This wide frequency range, combined with high dynamic range, supports the testing of various electronic devices and systems. It features advanced measurement options including occupied bandwidth, adjacent channel power, and sensitivity measurements, which are critical for compliance testing in communication systems.

Lastly, the E7402A is designed for users who require a spectrum analyzer with enhanced functionality at a competitive price. It reaches frequencies of up to 1.5 GHz, making it suitable for various applications including RF design, development, and manufacturing. Its user-friendly interface ensures that both novice and experienced users can navigate its features with ease.

In conclusion, Agilent Technologies' E7403A, E7401A, E7404A, E7405A, and E7402A spectrum analyzers provide a robust set of features tailored to meet diverse industry needs. Utilizing sophisticated technologies, these models ensure precise and efficient signal analysis, making them indispensable tools for engineers and researchers in the fast-paced world of electronics.
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