readme.txt

来自「用VB编写的dBm到Vrms（有效值）的相互转换程序」· 文本 代码 · 共 16 行

dBm(50ohm)       Voltage
+23.98             3.53 VRMS
+13.01             1.00 VRMS
+6.99		   500  mVRMS
0.0		   224  mVRMS	
-6.99		   100  mVRMS	
-13.01              50 mVRMS

dBm(75ohm) = dBm(50ohm) -1.75
dBm(600ohm) = dBm(50ohm) -10.79


dB=10*log10(P/Pref)
dBm=10*log10(P/0.001)  Pref=1mW

P=V*V/R