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Re: RAgeo, a low cost GEO bird



According to the ITU the minimum sky noise level is 18 dB at 30 MHz. At
140 MHz it is 3 dB and at 450 MHz it drops to -7 dB. The noise level at the
Earth's surface never goes much below 0 dB so an omnidirectional antenna is
close to 0 dB at 450 MHz. A small beam eliminates ground noise.

73,

John
KD6OZH

----- Original Message ----- >
It appeals to me because it is a big band and under used most of the time.
> When it is useable, you dont need the satellite either.  Further, its path
> loss  (to a similar scaled antenna) is 23 dB less than at UHF.  But using
> it as a downlink has to subtract from that, the atmospheric noise on that
> band (anyone know what this typically is in dBm?
>


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