New-Tech Magazine Europe | Dec 2015 Digital edition

Making Quick and Easy Measurements of Cables in the Field with FieldFox Tom Hoppin, Keysight Technologies, Inc.

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location is determined, the next step is to understand what the error is and repair it. During troubleshooting and maintenance, engineers and technicians can identify a fault’s location with Return Loss (RL) and Distance-to-Fault (DTF) methods, but they are unable to determine the cause or type of fault, making it difficult to repair. In many cases, the failures (e.g., loose or damaged connectors, water ingress or broken solder joints) can’t be seen by just looking at the cable. Also problematic is that measuring cable performance has traditionally required engineers and technicians to transport a cable and antenna analyzer, network analyzer, signal generator, and power meter into the field. That process is all the more complicated when the cables are used in systems located in hard to reach or even potentially hazardous environments. Once in place, the instruments would need to be correctly set up for testing. While effective, the process is error prone and leaves the instruments subject to accidental damage. Further complicating matters,

traditional vector network analyzers (VNAs) have difficulty making precise and repeatable high-loss measurements for in-situ microwave cables where test ports are long distances apart. Easier Cable Measurements with FieldFox’s Enhanced Cable Test Suite FieldFox’s new Time Domain Reflectometry (TDR) cable measurement option (Option 215) complements the analyzer’s current RL and DTF measurements. The RL measurement capability exposes mismatch of cable connections, while the DTF capability indicates the location of any faults or poor connections along the cable. The new TDR option provides engineers with new insight to help measure the impedance changes along the cable and identify the cause (type) of specific faults, such as short, open or water ingress. To date, FieldFox is the only handheld analyzer than can perform RL, DTF and TDR measurements in the same instrument. FieldFox’s TDR or step measurement

technicians typically experience multiple cable testing challenges in the field. Keysight Technologies recently introduced two innovative measurement options that make its FieldFox handheld analyzers the industry’s most comprehensive and effective cable test solution to meet these challenges head on. Cables (e.g., waveguide, coaxial and twisted-pair) are by far the most widely used components in modern RF and microwave systems like wireless and data communication, satellite communications and RADAR. They are also the leading cause of failure in these types of systems. That’s why their proper maintenance and using the right tool for testing in the field is so critical. The typical cable test process starts by determining whether or not a cable is faulty or performing outside the desired specification. If it is, the failure’s physical location along the cable must then be located. Once the Common Cable Test Challenges

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