How to reduce the failure of spectrum analyzer? What is the secret?

Are you still worried about the maintenance of your company's test instruments? I believe that many users have this worry. For device testing, accuracy, repeatability and reliability are crucial. Xi'an Antai Test and Maintenance Center provides maintenance services for oscilloscopes, spectrum analyzers, signal sources, network analyzers, digital multimeters and other electrical testing instruments. Based on years of maintenance experience, the main fault phenomena of spectrum analyzers are:

1. Power failure: cannot start up normally; 2. Input failure: abnormal impedance; no signal; abnormal signal amplitude; 3. Test and analysis failure: abnormal frequency and phase test; 4. Display failure: flowery screen; black screen; 5. Key failure: no response to keys; no response to adjustment knobs; 6. Interface failure: storage medium is not recognized; cannot connect to the control system; 7. Other usage problems, etc.

So how to avoid the above faults? Xi'an Antai Testing shares tips on how to prevent spectrum analyzer damage:

1. Read warning labels and technical specifications

Before using the instrument, please read the technical specification manual:

1. Do not exceed the parameter values ​​given in the Specifications Guide or the values ​​indicated by the yellow warning label on the analyzer. 2. Refer to the Specifications Guide for conditions required to achieve the listed specifications. Note the information regarding stabilization times, instrument setup, and calibration requirements.

This article takes E4440A as an example: The yellow warning label on the front panel of E4440APSA indicates that the maximum applicable RF input power is 30dBm (1W) and 0Vdc DC coupling voltage or 100Vdc AC coupling voltage. Therefore, the measurement range must not exceed the indicated range during use, otherwise the instrument will be damaged.

2. Do not input too much power to the analyzer

Take the E4440A spectrum analyzer as an example:

1. Limit the signal level to be measured with the spectrum analyzer to avoid front-end damage. Applying too much power to the front end may cause damage to front-end components. Typical maximum RF input signal level is 30dBm1W). 2. Turn off the DUT/signal source or reduce the power of the DUT/signal source before turning on or off the connected equipment or DUT. This helps prevent unexpected voltage increases or decreases that affect the input or output of the analyzer. 3. Use DC blocks, limiters, or external attenuators as needed.

3. Ensure proper grounding

Ensure proper grounding when using the instrument

1. Always use the three-phase AC power cord that comes with the analyzer. 2. Ground the instrument properly to prevent the accumulation of static charge. The accumulation of large amounts of static charge may cause damage to the instrument and personal injury to the operator. 3. Do not use extension cables, power cords or autotransformers without protective grounding conductors to avoid damaging the grounding protection. 4. Check the quality and polarity of the AC power supply; the AC voltage usually required is 100V, 120V, 220V±10% or 240V+5%/-10%. The expected ground wire resistance is usually <1Ω, and the voltage between the neutral wire and the ground wire is <1V. Install an uninterruptible power supply [UPS] if necessary.

4. Pay attention to electrostatic protection, especially the electrostatic protection of all exposed interfaces.

1. Electrostatic discharge (ESD) may damage or destroy electronic components. Therefore, testing should be performed at an anti-static workstation as much as possible. Keep all components at least 1 meter away from materials that may generate static electricity. Before connecting the coaxial cable to the analyzer, short-circuit the center and outer conductors of the cable together to ground. 2. Install ESD protective covers on all RF connectors before transporting and moving equipment.

5. Be careful to avoid hot plugging of interfaces: connect the interface first, then add the signal; disconnect the signal first, then disconnect the interface;

1. Avoid bending cables repeatedly. Bending at too sharp an angle can damage the cable immediately. 2. Limit the number of connections and disconnections to reduce wear and tear. 3. Inspect connectors before using them; check for dirt, cracks, and other signs of damage or wear. A faulty connector can quickly cause a good connector to fail. 4. Always use a torque wrench and gauge tool to connect RF connectors. 5. Clean dirty connectors to avoid affecting the electrical performance of the connection or damaging the connection.

6. Ensure that the instrument works in a suitable environment:

1. Maintain proper ventilation and humidity conditions

Generally, instruments and equipment should work in a suitable environment: temperature: 5℃-40℃?, relative humidity: 20%-80%, and avoid strong electric/magnetic fields, dusty environments and direct sunlight, and stay away from earthquake sources, water sources and corrosive gases, etc. For some special instruments used in special environments (such as aviation/mining/deep water, etc.), there are special requirements such as waterproof/high temperature resistance, etc.

2. When installing the product in the chassis, the air convection channel in and out of the instrument must not be blocked. For every 100W of power consumed by the chassis, the ambient temperature must be 4°C lower than the maximum operating temperature of the product. If the total power consumption of the chassis is greater than 800W, then forced ventilation must be used.

Of course, the above points are to help you take precautions and reduce the chance of your spectrum analyzer getting "sick". If your instrument has already failed, it is recommended that you find a regular maintenance center to "diagnose" it and "treat" it as soon as possible.