Near Field Probe Set: Basics, Applications, and Vendors

This page describes the basics of a Near Field Probe Set, its applications, and lists some of the vendors or manufacturers. A near field probe is used for both magnetic field (H-field) and electric field (E-field) measurements. Consequently, there are two main types: H-probes and E-probes. These probes are usually coated with an insulation layer, making them suitable for safe measurements near main power lines and oscillator devices.

The figure below shows a complete set of near field probes manufactured by Aaronia AG, Germany.

The RF near field probe set can be easily interfaced with a spectrum analyzer or oscilloscope, using a suitable adapter if needed.

Near Field Probe Applications

Here are some common applications of near field probe devices:

• Used to locate sources of interference
• Used to estimate the strength of interference fields
• Used to verify the effectiveness of shielding
• Used to verify the effectiveness of filters in a design
• Used to identify faulty or leaky components
• Used to detect circuits that are particularly sensitive to radio interference

Near Field Probe Manufacturers or Vendors

The following are some of the manufacturers or vendors of Near Field Probes:

• Tektronix (manufactures a near field probe kit)
• ETS-Lindgren (E & H near field probe set)
• Beehive Electronics
• Keysight Technologies
• Rohde & Schwarz
• Aaronia

Benefits of Near Field Test Probe

Following are advantages of near field probe used in test and measurement of EM signals for various applications.

1. Accurate EMI/EMC Diagnostics : Helps detect and locate electromagnetic interference (EMI) sources in electronic circuits and PCB designs.
2. Non Intrusive Testing : Measures electromagnetic fields without direct electrical contact, ensuring circuit integrity remains unaffected.
3. High Sensitivity : Captures weak signals for precise identification of noise sources and radiation hotspots.
4. Supports PCB and IC Debugging : Useful for analyzing electromagnetic emissions from components, traces, and connectors in circuit boards.
5. Compatible with Spectrum Analyzers & Oscilloscopes : Works with test equipment to visualize and analyze EMI characteristics effectively.
6. Aids in EMI Shielding Effectiveness Testing : Evaluates the efficiency of shielding materials in suppressing unwanted emissions.
7. Portable & Easy to Use : Compact, lightweight design allows quick field and lab measurements for troubleshooting and compliance testing.
8. Cost Effective EMI Analysis : Provides an affordable alternative to full anechoic chamber testing for pre-compliance evaluations.

Conclusion

A Near Field Test Probe is an essential tool for EMI/EMC testing, circuit debugging, and pre-compliance evaluations in electronic designs. By offering high sensitivity, non intrusive measurements, and compatibility with test equipment, it enables engineers to detect, analyze and mitigate EMI issues efficiently. Its portability and cost effectiveness make it a valuable asset for R&D, manufacturing and compliance testing, ensuring better electromagnetic compatibility and signal integrity in modern electronic devices.