Saelig Company recently announced the availability of the TBPS01-TBWA2 EMC Probe Kit (Singapore-based Tekbox Digital Solutions), which includes investigative near-field probes and a wideband amplifier to increase the versatility of economical spectrum analyzers to identify EMC issues. The TBPS01-TBWA2 EMC Probe Kit comprises four rubber-handled near-field probes (three H-field and one E-field), a 20- or a 40-dB wideband amplifier, and associated cables. The shielded probes have built-in ferrites and insulated rubber handles to insure that measurements are insensitive to the human hand.
The H- or E-field probes are useful for detecting radiated emissions when placed near potential sources of electromagnetic radiation, and can help locate and identify interference issues in electronic assemblies and PCBs. Scanning the probe over the surface of a PCB assembly or housing quickly identifies locations which emit electromagnetic radiation. The probes act as wide bandwidth antennas, picking up radiated emissions from components, PCB traces, housing openings, or gaps—and from any other parts that could be emitting unwanted RF signals. The probes are usually connected to a spectrum analyzer but may also be used (less effectively) with the FFT capability of a digital oscilloscope. By changing to a probe with smaller size, the origination of the emissions can be further narrowed down.
Engineers usually have to rely on experience and best-practice methods in order to design an EMC-compliant product. But when it comes time for compliance testing at an authorized test house many products fail first time through. Failing is expensive, and retesting costs are high too. The project schedule gets delayed and market introduction targets are missed. Therefore, it is essential for an engineer to do pre-compliance testing in-house to increase the chances of success when it comes time to book space in an anechoic chamber. One of the key components of an in-house pre-compliance test set-up is a spectrum analyzer. Entry-level models are now very affordable but the near-field antennas often are not. The TBPS01-TBWA2 EMC Probe Kit is an affordable antenna kit and amplifier that will enable any spectrum analyzer to be used to localize the origin of emissions or immunity compromises. Scanning the board with these hand-held probes will help identify problem areas, as well as the subsequent effectiveness of experimental solutions. An additional use of the probe kit with a signal generator is to identify PCB areas that are susceptible to RF interference by locally transmitting signals from the probes.
The included USB-5V-powered TBWA2 Wideband Amplifier, housed in a compact metal box (1.9″ × 2.6″ × 1″) provides either 20- or 40-dB amplification (depending on model) with a flat response from 10 MHz to 3 GHz, increasing the sensitivity of near-field probe measurements when attached to a spectrum analyzer.
Applications include radiated EMC measurements, contactless (load free) relative measurement of RF signal chains, contactless (load free) relative measurement of oscillators, modulators, RF immunity testing (by feeding a RF signal into the probe and radiating it into potentially susceptible circuit sections), noninvasive measurement of RF building blocks such as modulators or oscillators, and more.
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