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Re: trk results uo11 and ao40 Re: AO-40 S-Band Test



Hello Chris

I'm about to finally put up some S band RX equipment, but I'm a bit
concerned that with a 9' dish and 35dBi of gain your S/N is only 14dB. I was
looking at an antenna gain of about 17dBi - clearly way out!

It might explain why my few portable forays have been so far unsuccessful in
picking out AO-40.

Of course, I could be mis-interpreting your figures.

73 Howard G6LVB

> Eff. antenna diam.  = 2.76 meters   = 9.0551 ft
> Illum. Efficiency  = 75 %
>   Computed Antenna Gain = 3.6E+03 Ap  = 35.6 dBi
>   Antenna Half Power Beamwidth = 4.7E-02 radian  =   2.7E+00 degrees
>   Drift Scan time (zero declination) = 1.1E+01 min  =   640.4 sec
>   Recovered Power =   P inc + G ant  =   -137.9 dBm
>   System Noise Temperature = 50 K   =   -7.6 dB/To
>   Detector Noise Bandwidth = 164 Hz  =   22.1 dB/Hz      << post process
> spectrum fft size bandwidth
>   Receiver Noise Threshold  =   kTB  = 1.1316E-19 J/S  =   -159.5 dBm
>   Integration Time = 2.50E-04 sec  =   -6.9 dB/cy
>
> SIGNAL TO NOISE RATIO     14.6 dB         < measured from the audio file
>


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