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Post by M0ZIF on Apr 19, 2008 18:25:17 GMT
Classification | Mesurement | Freq | UHF | 33cm | 902 - 928 MHz | | 23cm | 1.24 - 1.3 GHz | | 13cm | 2.30 - 2.31 GHz and 2.39 - 2.45 GHz | SHF | 9cm | 3.3 - 3.5 GHz | | 5cm | 5.65 - 5.925 GHz | | 3cm | 10.0 - 10.5 GHz | | 1.2cm | 24.00 - 24.25 GHz | EHF | 6mm | 47.0 - 47.2 GHz | | 4mm | 75.5 - 81.0 GHz | | 2.5mm | 119.98 - 120.02 GHz | | 2mm | 142 - 149 GHz | | 1mm | 241 - 250 GHz |
UHF = Ultra High Freq SHF = Super High Freq EHF = Extremely High Frequency
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Post by ridgerunnr on Apr 20, 2008 0:59:02 GMT
Hey Martin-how ya doing? I have a question: why does it call for less wattage for transmit the higher the freq? Thanks-Frank
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Post by M0ZIF on Apr 20, 2008 8:06:22 GMT
The higher the frequency the less power needed, think about it this way, a Microwave oven uses say 700w and in 3 minutes will cook you scrambled eggs, would you want to be near a transmitter running 400w for any length of time? You'd cook. Due to the length of the Wavelength (or lack thereof) 1mW will be enough to transmit the same kind of distances that 10w on VHF. I don't know if your aware how much power is output by commercial satellites used as repeaters its usually under 5w peak. If you think about it due to the wavelength many applications use either a Satellite dish or yagi to send and receive on which gives you a very focused beam of signal. I hope this helps if your still not sure shout back
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