"Sal M. Onella" wrote in
:

....
Chart values do decrease at 6 dB per S-unit but the chart sets -72
dBm/56.8 uV as S-9, vice 73 dBm, 50 uV. 1 dB isn't much to quibble
about, but it does make me inquire about the source of the data.

Actually, it is 146dB lower than that... 50µV in 50 ohms is -73dBm.

Owen