[amsat-bb] updated my P3D link budget

[Franklin Antonio <antonio@xxxxxxxxxxxx>]

I've posted another iteration of my P3D link budget spreadsheet at
http://members.aol.com/n6nkf/

Several folks made useful comments re the earlier versions, and I've 
incorporated some of those changes.

The spreadsheet now shows a full loop from earth thru satellite and back to 
earth (up 1.2GHz, down 2.4GHz), as well as some other cases for the uplink 
only.

A full link budget thru the satellite requires knowing the transponder 
gain, and that's one number that I have as yet been unable to obtain.  To 
fix that, I GUESSED.  If someone would like to enlighten me with real 
transponder gain numbers, I would be most appreciative.

On prior transponders, the transponder gain was a single number (although 
it was never printed anywhere that I could find).  On P3D, with all the 
combinations possible, one needs a transponder gain number for each up/down 
combination.  I presume that during design some system was devised for 
calibrating the gains of each receiver section and transmitter section so 
that when connected by the IF matrix in every possible combination, a 
transponder gain that makes sense.  However, so far I'm not in on the 
scheme, so it remains a mystery.

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