What is EMF and how is it related to dBuV and dBm?

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Rayengine

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What is EMF?

Dear All,

I always found a unit (EMF) in RF Signal Generator, IC specification, but I don't know the exact meaning of the figures. How is unit related to common unit likes dBuV and dBm. Please help!

BR
Rayengine
 

EMF may be ( electro motive force ) or "volts"
 

Re: What is EMF?

It does stand for electromotive force which is measured in volts. For some reason people like to say volts instead of emf although they say current and not amps.
 

Most people say voltage, which is measured in volts.
Voltage and volts is not the same.
Just like current and amps is not the same.
Both EMF and Voltage are measured in volts.

EMF is the voltage without the voltage drop from the internal ouput resistance of the signal generator.
Therefore the real output voltage is always lower than the EMF.
The output voltage changes with changing current draw. The EMF never changes.
Only when you draw no current, the output voltage is as high as the EMF.

If your signal generator has an output resistance of for example 50 ohms, then you can calculate the output voltage if you know the EMF and the current.

Please read this document:
**broken link removed**


Another link:
http://hyperphysics.phy-astr.gsu.edu/hbase/electric/elevol.html
 

Re: What is EMF?

In physics type things like electromagnetic field theory, the line integral of the electric field is called emf and measured in volts.

In circuits text books from 75 or more years ago, ideal voltage generators used in the circuit analysis examples were labeled as having an emf of so many volts.
 

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