Questions about cables
Can you recommend good cables to connect the J2101A to a DUT?
About the PDN Cable SMA connectors. I read here that brass SMAs should be torqued to 3-5 in-lbs: https://www.microwaves101.com/encyclopedias/connector-torque
SMA (stainless steel) 7-10 in-lbs (~1Nm)
SMA (brass) 3-5 in-lbs (~0.4Nm)
PDN cables have brass SMA connectors, but you recommend that we torque to ~1Nm – is that correct?
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PDN Cable is ideal, since it has lowest shield attenuation and also shield resistance. RG58 or equivalent isn't quite as good, but it's inexpensive and readily. Keep it short and that will help minimize the impact. The bigger issue with the inexpensive cables is that the crimps aren't usually very good.
The 1Nm is the recommendation of our connector manufacturer. I generally use 0.4Nm since I have that wrench already. You'll notice in my demos I generally don't use the wrench so I can change connections quickly. At these low ish frequencies it has little impact. In the SI world it is much more critical, since a loose connector can exhibit some excess inductance. I showed that in my Power Integrity book.
Some helpful links:
https://www.signalintegrityjournal.com/blogs/8-for-good-measure/post/1441-what-makes-pdn-cable-special
https://www.picotest.com/blog/why-specialized-pdn-cable-is-essential-for-your-power-integrity-impedance-testing/