A scalar RF network analyzer?

Let’s see if I can measure my homebrew step attenuator as if I have an scalar network analyzer.

The following figure shows what a true scalar network analyzer is.

http://literature.cdn.keysight.com/litweb/pdf/5990-4798EN.pdf

Also see http://www.microwavejournal.com/articles/2277-applying-error-correction-to-network-analyzer-measurements

The traces, from top (red) to bottom (blue), correspond to -20dB, -30dB, -37dB, and -40dB positions of the attenuator, respectively.

There is a significant ripple, perhaps due to the fluctuations of either the output level of the SG or the sensitivity of the receiver.

If you normalize the responses assuming that the -40dB response is flat, you will get the following figure.

Or the following figure, if the -20dB response is assumed to be flat.

Please also read my article SMA Calibration Kit (2) for the measurement of the same attenuator with AA-30.ZERO.

It seems that the frequency response of the attenuator is reasonably flat up 30MHz.