fizzbang

Thanks! Forgot to mention that I'm using the BNC adapter with grabber cables which makes the GND status a bit unclear since there's GND, SGND, and WGND, and Ch1 and Ch2 share the one SGND. This produced rather a odd plot: but then bypassing the BNC adapter produced something fairly similar: I'll have to grab a known-good filter to see whether this is operator error or the one I'm testing is the problem, it's of unknown age so I don't know what state the electrolytics are in.

I'm trying to characterize the approximate performance of a black-box (potted) DC power filter which includes a common-mode filtering component, presumably it'll be similar to one of these. Problem is all the instructions for using the Network Analyzer assume the existence of a common ground point to connect Ch1-/Ch2-/W1- to, however in this case there's two locations, the filter input (before the choke) and the filter output (after the choke). How do you connect Ch1/Ch2/W1 to measure the frequency response of such a circuit? (I'm ignoring source and load characteristics and other complications for now, I just want to get a general overview of what the filter is doing).

Sure, I realise you can compensate for it but was more concerned that there appeared to be an error in the documentation that might confuse some people.

Not sure where the appropriate place to post this is, but it seems like there's an error in the Using the Network Analyzer manual page. It looks like Ch2+ is connected to the input of the RC filter and Ch1+ to the output, so the two have been swapped. This seems to be confirmed by the plot shown further down in "Run the Network Analyzer", in which C2 is showing the flat input while C1 is showing a response curve, even though the small diagram on the top right of the image shows C1+ at the input and C2+ at the output. Or am I misinterpreting something there?