The surface mount (SMD) capacitors used in this challenge are difficult to connect to instrumentation without soldering them into a test circuit. To facilitate some of my scope and pulse generator measurements I made a simple test fixture that uses spring loaded "pogo" probes to contact the SMD contacts on the capacitors. I can then connect the instruments to the test fixture and I can also add other components. I had planned to print alignment frames for the various capacitor sizes to align the contacts to the pogo pins. And also to print a "plunger" to press the capacitor into the socket frame. Unfortunately, my 3D printer is still out of commission as I haven't been able to get a new nozzle for the hot end yet. So, I modified a small plastic modelers clamp to apply the hold down pressure and I have to do the contact alignment by eyeball.
Pogo Probes:
Short video showing the fixture with capacitor attached:
Here is the fixture being used to measure the capacitance and ESR of the polymer capacitor that I am going to use in my buck converter test:
And here are the scope measurements:
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