Well, I don't know the formula, but the way I would do it is figure the
plus and minus db numbers. Let us say you have a duplexer los of 3 db,
feed line loss of 2 db, and an overall antenna gain of 7db, you'd have a
gainoverall of 2 db which I'd plug into the db formula for the 75 watts.
73s
Butch Bussen
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