@beanflying
I got the tracking generator working. I don't think it's performing quite as well as the one demonstrated by DS instruments in this youtube video:
...however it's a start! Keep in mind that the one in the video is the newer revision that has a signal generator onboard, so none of this bodging with another signal generator required. And I've got a breadboard in the mix. And I'm powering them off my powered USB hub, so there's likely some improvements to be made. I stupidly don't have any coaxial filters handy, but I attached some pics of a couple of pads and a nasty mix of cheap Chinese amazon special cables connected by a cheap SMA tee with the third port unterminated.
Those cables and connectors are likely going to go intro the trash soon, as I'm collecting better stuff.