A simple, but quite useful upgrade to my TC1 Multi-Function Tester.
I added a 3mm stereo jack, connected to the test socket pins 1,2, and 3.
Then made a few test leads with 3mm plugs and various probe clips to use with it.
It adds a few pF capacitance, but that can be allowed for.
(Just don't use a metal plug like I dumbarsedly did.)
A video about it:-