Tyler Stewart wrote:
>
> The MP is full scale at S9 + 60 DB, which Yaesu sets for +100dbu.
> That would make S9 a +40dbu, which tranlates to 50 microvolts
> on a 50 ohm sig. gen.
>
Could someone please explain this ????
It is my job to know things about dBu, dBm, uV, etc, but this conversion
is totally unclear to me!
Isn't it dBu = 20log(U/1uV) ?
where:
U is expressed in volts,
1uV is what it looks like it is:) and
'log' is a base ten logarythm.
So, 50uV/1uV = 50 -> 20log(50) = 33.979dBuV
And +40dBuV would be: 10^(40dBuV/20)*(1uV) = 10^2 = 100uV
If you write it down on paper it's much more clear.
And for power it's dBmW = 10log(P/1mW)
Hmm...unless you mean dBuW when you say dBu ? (which almost sure doesn't
fit into my definition, too :)
73 de YT1ZKB
zoran
kn04ft
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