- Joined
- Apr 12, 2013
- Messages
- 562
I actually recognize that problem! If I approached the 'which scope is bad' issue the same way I do control and instrumentaiton failures in my normal (engineering) job, there are several solutions. 2 out of 3 checks are the quickest, mount 3 and see if 2 agree. Odds are VERY high the odd one out is the bad one, or at minimum you see 3 different results if 2 (or all 3) are bad. Otherwise process of elimination works. 3 scopes, compare 2, different readings, swap one, check again, still different==one that stayed is bad, read same==one swapped out is bad. It helps to have a known good (or at least trusted) instrument for reference. Or to put it another way, if A=/=B and A=/=C and B==C then B and C are good, A is bad. Classic 2 out of 3 testing for failure. That is a lot easier for us laymen than building a locked down scope for the testing. I could mount a couple of rails on a single heavy aluminum block for comparing, I could not dissect the internals of a nice scope for such an operation!