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14

You didn't include antenna gain at all. That number for the path loss is a starting point assuming zero gain (isotropic antennas) on both ends. This isn't a realistic situation, because of course the vast majority of the signal from an isotropic antenna doesn't reach the moon at all, but it's conventional for calculating link budgets. A 9-element Yagi has a ...


8

You can find the code in packjt77.f90. Callsign encoding (for "standard" callsigns that don't require hashing) is in function pack28. A quick summary: Adjust a few strange prefixes that don't follow the usual arrangement of letters and numbers. Swaziland 3DA0* will be encoded as if it was 3D0* instead, and Guinea 3XA1A will be encoded as if it was ...


3

From the linked manual: Notice these sensitivities each specify a mode, and some threshold (10 dB S+N/N, 12 dB SINAD). For digital modes a bit error rate (BER) would be specified. Some modes are more sensitive than others. For example, WSPR takes 2 minutes to send a call, transmit power, and grid square, whereas the SSB transmission of the same information ...


3

RE: ...So what is actual relation between path loss, receiver sensitivity, and also used power and antennas gain? The Friis transmission equation is useful to determine such for a free-space, far-field propagation path (see the example below).


1

If you're OK with an approximation, the solid angle can be calculated with much simpler math. An isotropic antenna must radiate over a solid angle of 4π because it radiates in all directions. An antenna with a gain of (for example) 20 dBi has a gain of 100x, which means in the direction that gain is quoted, the power flux density must be 100x what it would ...


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