PHASE MODULATION

CALIBRATION

(￿M) CALIBRATION

￿M

Calibration

Procedure

CENTER FREQUENCY

 

BESSEL

 

NULL

Figure 4-16.

Typical Spectrum Analyzer Display

of Bessel Null on FM Waveform

NOTE

You may need to adjust the RBW setting on the Spectrum Analyzer in order to see the >–40 dBc null.

4.Connect the 682XXB/683XXB RF OUTPUT to the Spectrum Analyzer RF Input.

NOTE

Before beginning this calibration proce- dure, always let the 682XXB/683XXB warm up for a minimum of one hour.

The following steps in the procedure lets you cali- brate the FM Variable Gain Control DAC and the ￿M Flatness DAC in both Wide and Narrow ￿M modes and store the results in non-volatile memory (EEPROM) on the A17 CPU PCB.

NOTE

To ensure accurate calibration, each step of this procedure must be performed in se- quence.

1.External Wide FM Mode Sensitivity calibration is accomplished by adjusting the FM Variable Gain Control DAC to reduce the carrier level as low as possible at frequencies of 5 GHz and 20 GHz. The modulating signal input is from the external Function Generator.

Perform the calibration as follows:

a.At the $ prompt, type: calterm 149 and press <ENTER>.

b.Set up the Function Generator for a 99.8 kHz sine wave with an output level of 0.707 volts RMS (2 volts peak to peak). Use a frequency counter to verify the output frequency of your function generator is set to ￿1%.

c.On the Spectrum Analyzer, set the Span/Div to 50 kHz per division.

d.On the computer keyboard, use the ‘, 1, 2, and 3 keys to increment and the 7, 8, 9, and 0 keys to decrement the value of the DAC’s setting.

Start calibration by pressing an increment key.

e.While observing the first Bessel null (Figure

4-16) on the Spectrum Analyzer display, adjust the value of the DAC’s setting to reduce the carrier level as low as possible.

f.When finished setting the DAC, press Q on the keyboard to go to the next calibration step.

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682XXB/683XXB MM

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Anritsu 682XXB, 683XXB manual Calibration Procedure
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682XXB, 683XXB specifications

The Anritsu 683XXB and 682XXB series are advanced vector network analyzers (VNAs) renowned for their precision and versatility in characterizing RF and microwave components. Designed for engineers and technicians involved in the development, manufacturing, and testing of high-frequency devices, these analyzers offer state-of-the-art technology that ensures optimal performance in various applications.

One of the hallmark features of the Anritsu 683XXB and 682XXB is their high dynamic range, which allows for accurate measurements of small reflection and transmission coefficients, essential for assessing the performance of complex RF structures. With frequency coverage extending from DC to 70 GHz, these analyzers cater to a broad spectrum of applications, making them suitable for industries such as telecommunications, aerospace, and automotive.

The user-friendly interface of the Anritsu VNAs is complemented by a high-resolution display, which facilitates easy navigation through measurement setups and results. The analyzers feature multiple measurement modes, including S-parameter measurements, time-domain analysis, and noise figure measurements, providing engineers with comprehensive tools for device characterization.

Both the 683XXB and 682XXB implement advanced calibration techniques, including automated calibration and error correction methods, to enhance measurement accuracy. These methods significantly reduce the uncertainties associated with test setups, enabling reliable performance evaluations of components like filters, amplifiers, and antennas.

Anritsu’s proprietary technologies, such as the VectorStar and ShockLine series integration, further empower the 683XXB and 682XXB models. These technologies enable high-throughput testing and improved measurement stability, addressing the needs of modern production environments that demand rapid turnaround times without sacrificing precision.

Additionally, the analyzers come equipped with various connectivity options, including USB, LAN, and GPIB, ensuring seamless integration into automated test systems. This adaptability enhances the analyzers' utility in both laboratory settings and field operations.

In conclusion, the Anritsu 683XXB and 682XXB series vector network analyzers represent the pinnacle of RF and microwave testing technology. With their unmatched precision, comprehensive measurement capabilities, and advanced calibration techniques, these instruments are indispensable tools for professionals striving to push the boundaries of high-frequency device performance and reliability.
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