Conversion of Power
(dBm to Milliwatts) to rms volts
(50 and 75 ohms)

Power
dBm
Power
mW
Vrms
(50 ohms)
Vrms
(75 ohms)
-30.00 0.00 0.01 0.01
-25.00 0.00 0.01 0.02
-20.00 0.01 0.02 0.03
-15.00 0.03 0.04 0.05
-13.00 0.05 0.05 0.06
-10.00 0.10 0.07 0.09
-9.00 0.13 0.08 0.10
-8.00 0.16 0.09 0.11
-7.00 0.20 0.10 0.12
-6.00 0.25 0.11 0.14
-5.00 0.32 0.13 0.15
-4.00 0.40 0.14 0.17
-3.00 0.50 0.16 0.19
-2.00 0.63 0.18 0.22
-1.00 0.79 0.20 0.24
0.00 1.00 0.22 0.27
1.00 1.26 0.25 0.30
2.00 1.58 0.28 0.34
3.00 2.00 0.31 0.38
4.00 2.51 0.35 0.43
5.00 3.16 0.39 0.48
6.00 3.98 0.44 0.54
7.00 5.01 0.50 0.61
8.00 6.31 0.56 0.68
9.00 7.94 0.63 0.77
10.00 10.00 0.70 0.86
15.00 31.60 1.25 1.54
20.00 100.00 2.23 2.73
25.00 316.20 3.97 4.87
30.00 1,000.00 * 7.07 8.66
40.00 10,000.00 ** 22.30 27.30

* 1 watt
** 10 watts

by Mike Morris WA6ILQ
(callsign) at arrl dot net
HTML copyright Michael R. Morris 2004,
original information provided by Neil McKie WA6KLA
Last modified 04 August 2004