Using the nice calculator Erik pointed to, and the fact that the text specifies? 0.5?V = 0 dB?:
From the calculator, ?0.5?V =? -6 dB?V?
So -6 dB?V corresponds to 0 dB?.
So subtract 6 from each of the dB? values in your instructions to convert to dB?V, then use the calculator to convert dB?V to dBm, giving:?
9 dB? -> -104 dBm
6 dB? -> -107 dBm
0 dB? -> -113 dBm
36 dB? -> -77 dBm
86 dB? -> -27 dBm
25 dB? -> -88 dBm
