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P. C. Electronics  2522 Paxson Lane  Arcadia ... 1-626-447-4565
P. C. Electronics 2522 Paxson Lane Arcadia ... 1-626-447-4565

... Diamond F718x antennas with >20 ft separation is also used. A simple starter antenna for home or portable is the ground plane you can make yourself - see our application notes web page. For every 6 dB of increase between two fixed points, you will gain one P unit or double the distance to a farther ...
An improved method to measure the antenna resistance and
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... the calculation, the transmission line was divided from the output of the matching system till the end of the vacuum feedthrough line into short sections with a maximum length of 0.1 m. The different characteristics of the lines like conductivity and diameters of inner and outer conductor were used ...
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... 3V3 alarm The internal 3V power supply is outside of the allowable range. Possible causes are: 12V power supply is outside of allowable range: Internal failure ...
Dipoles For Dummies, Part 1 -- Basic
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... Note, that even in the case of the monopole no “ground” is needed to operate. Referring to our clapping analogy again, consider the case where you are asked to clap with one hand in your pocket. You take your free hand and find something to clap against such as your desk, a table, or wall, that’s ex ...
Senior Project Proposal - University of New Hampshire
Senior Project Proposal - University of New Hampshire

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... trapped antennas. They cover the 10-15-20 Meter Bands but not the WARC bands 12 & 17 M. The reason that there are so many is that they have been around much longer, since they were designed before the WARC bands were created. Also, they are in demand by contesters where only the non-WARC bands are u ...
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投影片 1
投影片 1

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Characteristic Study ofMicrostrip Patch for Different Substrates
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IOSR Journal of Electrical and Electronics Engineering (IOSR-JEEE)
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... also to be considered. The main future challenge of the global EM-Matrix project is to achieve the complete embedded acquisition system. Coupled to a signal processor, it should be a convenient system for both real time calibration and control of the chips under the module, so to optimize the switch ...
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... Special thanks go to the Departments of Electrical Engineering, Technology, and Space Studies at the University of North Dakota for participating in this project and providing the equipment necessary for manufacturing and testing. We also would like to thank the following individuals: Dr. Hossein Sa ...
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Near and far field



The near field (or near-field) and far field (or far-field) are regions of the electromagnetic field around an object, such as a transmitting antenna, or the result of radiation scattering off an object. Non-radiative 'near-field' behaviors of electromagnetic fields dominate close to the antenna or scattering object, while electromagnetic radiation 'far-field' behaviors dominate at greater distances. Far-field E and B field strength decreases inversely with distance from the source, resulting in an inverse-square law for the radiated power intensity of electromagnetic radiation. By contrast, near-field E and B strength decrease more rapidly with distance (with inverse-distance squared or cubed), resulting in relative lack of near-field effects within a few wavelengths of the radiator.
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