I have two old Tek oscilloscopes that belonged to my father, one 475 that dates to at least 1975, and a 2213 from around 1982, both with the original passive voltage probes that he used for work (two P6075A probes for the 475, and two P6120 probes for the 2213, all x10 probes, non-switchable). One of the P6075A was marked "BAD" by my father some time prior to 1995, but, though he kept detailed notes, I have no other indication of what malfunction he observed. I have tried to evaluate the probes myself, but while I am not a rank amateur (I have a basic, college level understanding of electronics, understand Ohm's and Kerchhoff's laws, know how to handle a soldering iron, multi-meter, and even a bit about using an oscilloscope) I am barely a journeyman. I am likely to use the wrong terminology for some things, but I hope that my meaning is clear.
My question is what should I be measuring about the probes to determine whether they are "good" or not? I have used a fairly nice multi-meter to measure the resistance and capacitance from several points: the probe tip ("tip"), the grounding clip ("clip") (with the GND REF button pressed and not), the BNC center pin ("center"), and the BNC ring ("ring"). I have measured continuity from tip to pin, from tip to clip, and clip to ring. I have measured resistance from tip to center, and tip to ring (with GND REF button pressed). And I have measured the capacitance from tip to clip. I have also compared my measurements against a newly purchased third party probe (cheap P2200 off Amazon), and a refurbished Tek probe (cheap P6075A off eBay).
I have found that the contact between the ground clip and the probe shell/BNC ring has been unreliable on these old probes, but the probe that my father marked "BAD" seemed to be revived after I removed the ground wire and cleaned the spring clip that contacts the outer housing of the probe. Are there other measurements that I should be doing on a scope probe to determine if it is working?
Thanks in advance