After a lucky impulse buy of a 100MHz* scope last night, I may as well take advantage of combined shipping and grab some probes of which I am short. I need at least 2 more for my 250MHz TDS485. One would think that 250MHz probes would do the trick, but I don't know what the advertised probe frequency actually means. Does it mean the probe will add no measurable error to 250MHz measurements, or is it a classic -3dB (cutoff) frequency? And, at what input capacitance is this frequency set to? Surely, after adjusting the probe to match the 'scope, this value will change?
For example, if f_probe_cutoff is measured at a standardized 10 pF, but I then add 5 pF to match the scope, does it degrade?
Anyone have some experience in the area? ('Suppose that's most regulars...)
*it can be increased from 50MHz to 100MHz through software.