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LibreVNA manual - and port to on the selected port and commas

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Bryan Paradis 2025-02-25 17:29:11 -08:00
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Documentation/UserManual/manual.tex
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@ -1457,7 +1457,7 @@ These are the necessary steps:
\begin{enumerate}
\item \textbf{Set up the calibration frequencies:} Add or remove points according to your needs. Ideally, they should be evenly spaced across the calibration range, maybe with a slight emphasis on higher frequencies (signal levels generally vary more at higher frequencies). Additionally, it is advisable to set one point at \SI{25}{\mega\hertz} and another point just below it (at \SI{25}{\mega\hertz} a band is switched, resulting in an amplitude discontinuity). Up to 64 points can be used.
\item \textbf{Select the calibration mode:} Either calibrate both ports separately (best accuracy but more work) or assume that they are identical and use the measurement at one port for both.
\item \textbf{Perform the calibration:} For each frequency and port, select the corresponding cell in the table. The \vna{} will generate a signal at the selected frequency and port with (what it thinks are) \SI{-20}{\dBm}. Use external equipment to determine the actual output level and enter the measured value into the selected cell.
\item \textbf{Perform the calibration:} For each frequency and port, select the corresponding cell in the table. The \vna{} will generate a signal at the selected frequency, on the selected port, with (what it thinks are) \SI{-20}{\dBm}. Use external equipment to determine the actual output level and enter the measured value into the selected cell.
\item \textbf{Save the calibration:} Once all measurements have been taken, the "Save to Device" button becomes available. There is no way to save intermediate results, you have to calibrate all frequencies you have chosen in step 1.
\end{enumerate}
If the Receiver Calibration is already done, it is also possible to infer the Source Calibration from that. Press \keys{Automatic measurement} and connect both ports of the \vna{} directly to each other. This connection should be as ideal as possible (short, low loss cable) as every imperfection directly translates into calibration errors. During the automatic calibration, the \vna{} uses the already established frequency points from the Receiver Calibration and measures the output amplitude by itself to determine the coefficients of the Source Calibration.