Questions: Shielding and grounding

 

 

 

 

 

 

 

Question no. 1

An installation technician is offering you different ways of installing a set of cables that you want to protect from external interference up to 30MHz. He suggests the following. Which do you choose?
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Review: Parallel Earth Conductor

Question no. 2

Why should an RF bond strap have an aspect ratio (length vs. width) preferably 5:1 or less?
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Review: Bond straps

Question no. 3

What is the cutoff frequency and approximate attenuation to electromagnetic fields at frequencies well below cutoff, of a circular copper tube of 5cm inside diameter and 18cm long?
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Review: Waveguide below cutoff

Question no. 4

A plane electromagnetic wave at 870MHz is incident normally on a sheet of aluminium with μr=1, σr=0.636. At what depth into the aluminium does the current density due to the field reduce to 1 of its incident value?
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Review: Skin effect

Question no. 5

Your product has a number of analogue external interfaces on a double-sided ground plane PCB which takes up most of the enclosure width. It is housed in a 19" 3U high rack mounting metal enclosure with internal width 435mm, depth 253mm. It's found to suffer from radiated susceptibility particularly around 680-690MHz. What mechanism do you suspect first?
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Review: Shielding theory