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alphapointe
Don't Touch Me
Premium,MVM
join:2002-02-10
Columbia, MO
kudos:2
Reviews:
·Socket Internet ..

Unit Conversion Help

I just got a spectrum analyzer (Tek RFM151), but it's made for CATV, so it reports levels in dBmV instead of dBmW. Is there a simple way to convert from one to the other?




jacour
Premium
join:2001-12-11
Matthews, NC
Reviews:
·voip.ms
·Time Warner Cable

Wikipedia explains it better than I can.

dBmV

dB(1 mVRMS) – voltage relative to 1 millivolt across 75 Ù. Widely used in cable television networks, where the nominal strength of a single TV signal at the receiver terminals is about 0 dBmV. Cable TV uses 75 Ù coaxial cable, so 0 dBmV corresponds to 78.75 dBW (48.75 dBm) or ~13 nW.



SmokChsr
Who let the magic smoke out?
Premium
join:2006-03-17
Saint Augustine, FL
reply to alphapointe

I found a manual for it on line and it says you can change the units to dbuV not that that's going to help much..
»128.238.9.201/~kurt/manuals/manu···tion.pdf



Killa200
Premium
join:2005-12-02
Southeast TN

4 edits
reply to alphapointe

X = dBmV

anti log (X/20) = mV

mV^2 / Cable impedance = dBmW

If i remember correctly. From that math, i'm getting 3.7dBV = .0469dBW @ 50ohm, or 1.01watts.