Netwaork Analyser = Signal Gen. + Spectrum??

[david753]

If I only have a Signal Generator and Spectrum in my lab.
How can I measure a RF component as a Network analyzer by Signal Gen. and Spectrum?
How to get it phase delay?

 

[vfone]

You can't measure phase or delay using just a Signal Generator and a Spectrum Analyzer.
You need a Vector Network Analyzer, or at least a Vector Voltmeter.

 

[biff44]

depending on how desperate you were to do the test without renting a network analyzer, it could be done. You would have to set up a test that converted phase into amplitude (which can be viewed on the spectrum analyzer).

One way would be to phase modulate the signal source, split the modulated RF into two paths, send one path thru the device under test, and send the other path thru a physical length of coaxial cable. You then combine the two outputs and view the sidetones on the spectrum analyzer.

If you vary the length of the coaxial cable, at some point you can get the sidetone to null out. You group delay is roughly what the time delay in the cable is (you have nulled the phase variation in the DUT with the reference cable path). To get a good null, you might have to attenuate one of the paths.