Formulas & Data:
- Electronics
- Mathematics
- Physics
- RF & Microwaves

Parts Vendors:
- all hand-selected

- Amateur Radio
- Vintage Articles:
- Electronics World
- Popular Electronics
- QST
- Radio & TV News
- Radio Craft
- Short Wave Craft
- Wireless World

- Events Calendar
RF Cafe Homepage
Copyright 1999-2015   •−•  ••−•    −•−•  •−  ••−•  •   "RF Cafe" in Morse Code  >> Listen to It <<
- EW & Radar Handbook
- Quizzes       - Software
- App Notes
- Calculators
- Advertise on RF Cafe
- About RF Cafe™
- RF Cafe Shirts & Mugs
- RF Cafe Archives
RF Cafe Book Contest
- RF Cafe on Visit RF Cafe on Facebook Visit RF Cafe on Twitter Visit RF Cafe on LinkedIn
- Tech Humor
- Forums Archive
- Job Board
- Donate to RF Cafe
- Kirt's Cogitations
Custom Search
More than 10,000 searchable pages indexed.
Greetings: There is so much good stuff on RF Cafe that there is no way to list or link to all of it here. Please use the Search box or the Site Map to find what you want - there is a good chance I have it here. Thanks!

Power vs. Voltage in a 50 Ω System

A lot of people have a hard time converting between power and voltage in 50 Ω systems. The full derivation requires a little extra work because of the use of the root-mean-square value of a sinewave, based on its peak voltage value. Here's how it's done.

 

 

 

 

 

 

 

The Table of Equivalent Voltages & Powers was generated using an Excel spreadsheet. Equations for the cells are shown at the bottom of the table.

 

Voltage to Power (for a sinewave) in a 50 Ω System

Power -to - volts voltage equation forumla - RF Cafe  

Power -to - volts voltage equation forumla - RF Cafe
  where v is in volts

Power to Voltage (for a sinewave) in a 50 Ω System

Power -to - volts voltage equation forumla - RF Cafe  Volts

Table of Equivalent Voltages & Powers in a 50 Ω System
Vpeak(V)Vrms(V)Vavg(V)P(W)P(mW)P(dBm)
107.071076.366201.000001000.0000030.00000
96.363965.729580.81000810.0000029.08485
85.656855.092960.64000640.0000028.06180
74.949754.456340.49000490.0000026.90196
64.242643.819720.36000360.0000025.56303
53.535533.183100.25000250.0000023.97940
42.828432.546480.16000160.0000022.04120
3.1622782.236072.013170.10000100.0000020.00000
32.121321.909860.0900090.0000019.54243
21.414211.273240.0400040.0000016.02060
10.707110.636620.0100010.0000010.00000
0.90.636400.572960.008108.100009.08485
0.80.565690.509300.006406.400008.06180
0.70.494970.445630.004904.900006.90196
0.60.424260.381970.003603.600005.56303
0.50.353550.318310.002502.500003.97940
0.40.282840.254650.001601.600002.04120
0.3162280.223610.201320.001001.000000.00000
0.30.212130.190990.000900.90000-0.45757
0.20.141420.127320.000400.40000-3.97940
0.10.070710.063660.000100.10000-10.00000
0.090.063640.057300.000080.08100-10.91515
0.080.056570.050930.000060.06400-11.93820
0.070.049500.044560.000050.04900-13.09804
0.060.042430.038200.000040.03600-14.43697
0.050.035360.031830.000030.02500-16.02060
0.040.028280.025460.000020.01600-17.95880
0.0316230.022360.020130.000010.01000-20.00000
0.030.021210.01910 0.00900-20.45757
0.020.014140.01273 0.00400-23.97940
0.010.007070.00637 0.00100-30.00000
0.0090.006360.00573 0.00081-30.91515
0.0080.005660.00509 0.00064-31.93820
0.0070.004950.00446 0.00049-33.09804
0.0060.004240.00382 0.00036-34.43697
0.0050.003540.00318 0.00025-36.02060
0.0040.002830.00255 0.00016-37.95880
0.0031620.002240.00201 0.00010-40.00000
0.0030.002120.00191 0.00009-40.45757
0.0020.001410.00127 0.00004-43.97940
0.0010.000710.00064 0.00001-50.00000
FormulasVpk/SQRT(2)Vpk*2/PI()V2pk/(2*50)   PW*100010*log(PmW)

Your RF Cafe
Progenitor & Webmaster

Click here to read about RF CafeKirt Blattenberger… single-handedly redefining what an engineering website should be.

View the YouTube RF Cafe Intro Video Carpe Diem!
(Seize the Day!)

5th MOB: My USAF radar shop

Airplanes and Rockets: My personal hobby website

Equine Kingdom: My daughter Sally's horse riding website