[SOLVED] VAC to dbm conversion in RF mixer

[neazoi]

Hello an RF mixer of 50ohm input states on RF port 1vAC max.
How much is it in dbm or vpp?

 

[WimRFP]

If it is a peak value, P = V^2/2R = 1^2/100 = 0.01W = 10mW

10mW = 10*mW As we have powers, convert "10" to dB via 10*log10 = 10*1 = "10dB"

10 mW = 10dB*mW. As we are lazy sometimes, we write this mostly as 10 dBm.

When it is an rms value, the power V^2/R = 0.02W = 20mW, converting "20" to dBs gives "13dB", so together with the mW:

20mW = 13dBm.

1Vacpk = 2Vpp
1Vacrms = 1*1.414 = 1.414Vp = 2.83Vpp

rt(2) is the correction between rms value and peak value for sinusoidal waveform.