The first 10 years of EMC work for the JAS 39 Gripen Fighter Aircraft

The new version . of the JAS39 Gripen fighter is now a strong competitor in the fighter aircraft world market and the aircraft operates in several countries. A historical review of the early EMC work for the Gripen project may be of interest. The JAS 39 Gripen fighter aircraft project was outlined and presented in 1979-1981 by SAAB Military Aircraft & The Industry Group JAS also including the Ericsson Microwave Co. and Volvo Flygmotor. The development of the Gripen system and a production of 30 aircraft for the Swedish Air Force was decided by the Government in 1982. The decision was made after an intense debate in the media whether Sweden had the competence and capability to continue the independent fighter aircraft development although such projects had become extremely complex and costly.

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Ögat På: EMC från bricka till bricka, del 11

Vi fortsätter . att betrakta vår figur: ”EMC från bricka till bricka” och går vidare till filtrering av ledare och kablar. (F) EMC måste tas om hand i alla delar, såväl på elektrisk som på mekanisk systemnivå, och på alla nivåer i en utrustning på ett systematisk och planerat sätt.

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Tactical Consequences of Radio Spectrum Out-of-Band Properties

Tactical communications . for ground-based operations requires many co-located communication systems on combat vehicles. Typical frequency bands for such communications are the 30–88 MHz band for army combat radio and the harmonized NATO band 225–400 MHz. As a result of increasing demands of different communication services and larger bandwidth, the amount of co-located communication systems in these bands is continuously increasing. A consequence of this is that the used frequencies will be less separated, meaning that out-of-band properties will be of severe importance for the performance of the individual systems.

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Vem har tätpositionen inom EMC idag?

En redaktörs reflektioner . EMC-området har utvecklats i olika riktningar sedan det uppstod för runt 100 år sedan. Då utgjordes den drivande kraften av att man ville försäkra sig om att oavsiktlig elektromagnetisk emission från hushållselektronik inte skulle störa de nya rundradiotjänsterna.

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The Ten Commandments for EMC, part 3

EYE ON . Shielding is one of the concepts associated with EMC. Often, for example, mechanical engineers are tasked to build a shielding box, without further specification of ie operating frequencies or desired attenuation.
How much attenuation is reasonable to expect?

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Background and Comments on the EMC Performance of Cable Trays

The study . “On the EMC Performance of Cable Trays” started with a contact between EMC Services and the Defem company. Their problem was that their design had been given a lot of criticism in the standard EN 50174-2:2000 (on page 25). The standard was found to contain a lot of formulations on EMC, but there was no rationale for the text – nor were they complete.

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On the EMC Performance of Cable Trays

How to . improve EMC performances of cable installations. The major conclusion from the study is that cable trays are an integral part of the ground structure (actually, it forms the ground if correctly done; nothing else is needed), which can perform as a shielding structure for the enclosed electronic systems. The major quality parameter […]

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WHAT IS EMI/EMC?

Michel Mardiguian . Electro Magnetic Interference (EMI) is the generic term describing a situation whereas an electrical disturbance generated by a certain electronic/electrical equipment is causing an undesirable response to another equipment. This undesirable effect may range from a mere nuisance to a catastrophic failure, with associated financial losses or eventually human casualties. The origin of the disturbance could also be a natural phenomena like lightning strokes or ElectroStatic Discharges (ESD). ElectroMagnetic Compatibility (EMC) is just the opposite: EMI being the disease, EMC is the cure, that is the discipline analyzing and preventing or fixing interference problems.

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The Ten Commandments for EMC, part 2

EYE ON . One fundamental concept in EMC design is zoning. Zoning is easy to understand. It is used in the most varied contexts and situations. Situations covering everything from old communist dictatorships, such as for example the former East Germany (DDR), to city planners and the European Union. Zones are used in order to achieve various properties in demarcated geographic areas, or within volumes. Zoning with application in electronic engineering are also known as the Controlled Electromagnetic Topology.

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Ögat På: EMC från bricka till bricka, del 10

Vi fortsätter . att betrakta vår figur: ”EMC från bricka till bricka” och går vidare till signalöverföring. EMC måste tas om hand i alla delar, såväl på elektrisk som på mekanisk systemnivå, och på alla nivåer i en utrustning på ett systematisk och planerat sätt.

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