Amplitude ratio in network analyser mode : relative to Ref + Vrms ?

[Xavier]

Hello,

Using ADP3450 in network analyser mode, I made the mistake of using the "Relative to ref" option with "Vmrs" plotting option.

Actually, I understand it does not make sense to ask for an amplitude ratio in true units since it's a ratio...and can only be plotted as a linear or dB gain scale. And that the ambiguity come from the need to plot on the same graph, the Channel 1 in true units, whereas the other ones are asked in relative amplitude.

The attached file illustrate two measurements made with and without the "Relative to ref" option.

My question is : what is plotted when both "Relative to ref" and "Vmrs" are selected ? Is there a simple way to recover the RMS value or the Gain from measurement that have been made and exported with way)

Thanks for your help,

Xavier

 

testADPnetwork.pdf

[attila]

Hi @Xavier

Run the following script once to convert C2 from relative to absolute magnitude:
(For the next software version I'll try to make the relative option dynamic)

var c1 = Network.Channel1.magnitude; // in selected Unit
var c2 = Network.Channel2.magnitude;
var a = Network.Wavegen.Amplitude.value/sqrt(2); // for VRMS
var n = c1.length;
for(var i = 0; i < n; i++) c2[i] = c2[i]*c1[i]/a;
Network.Channel2.magnitude = c2;

[Xavier]

1 hour ago, attila said:

Hi @Xavier

Run the following script once to convert C2 from relative to absolute magnitude:
(For the next software version I'll try to make the relative option dynamic)

var c1 = Network.Channel1.magnitude; // in selected Unit
var c2 = Network.Channel2.magnitude;
var a = Network.Wavegen.Amplitude.value/sqrt(2); // for VRMS
var n = c1.length;
for(var i = 0; i < n; i++) c2[i] = c2[i]*c1[i]/a;
Network.Channel2.magnitude = c2;

 

Hi Attila,

Many thanks for your quick answer,

I was expecting something like a factor 1/2, but with the script it's much more clear

Best