KEYCOM provides solutions in the 300 GHz to 1 μHz frequency range (SHF/EHF/MW/UHF/VHF/ULF).
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Cavity type resonator method, Shield case material evaluation system for EMC measures

Model No. EMC71

It is used iron and aluminum for the material of back side case for plasma display or plastic with aluminum.
The hole of the case will be fixed with a conductive liner sheet.
The installation is performed through the electroconductive gasket, to avoid the case becomes antenna.
There is a big problem that it becomes a resonator, and an unnecessary electromagnetic radiation is leaked from the hole, due to 500 times radiation.
The electric wave absorption sheet covers the case and case will be conductive.
In other words an electric wave absorption function case will be a solution.
A system will be measured such materials.



・Frequency : 1GHz
・Specimen : Size 25mmX25mm Thickness 0.1~2mm
・Measuring instrument : Vector network analyzer, Scalar network analyzer, or synthesized sweeper with receiver
Wlndows PC ( GPIB boad with National Instrument driver 〉

Model No.

・Resonator kit
  COE-01 Resonator
  TMR-1D Resonator kit for 1GHz
  TMR-5D Resonator kit for 5GHz
  DMP-70 Program for EMC
  Coaxial cable assembly at 40GHz : 1m-2 pcs


・Network analyzer, Windovs PC and printer

Figure (1)


Table (1) Q value by this system of various materials and Q value of case

Material Q value of material Q value of case produced with left material Effect of EMC
Material none 6265
A 6133 2300 None
B 5635 2110 Normal
C 5370 2000 Better
D 5218 1950 Best

One example of the measurement screen when material C is measured is shown as below.
It is a resonance curve. Q value is indicated in a right part.

One example of measurement screen