>what's with probes anyway? Evidently a probe is more than just a wire
>with a spike on the end? Why are they sometimes so expensive/

A probe has to have a number of contradicting features such as:
1 - high impedance
2 - low capacitance (conflicts with 4)
3 - low radiation/susceptance (good shield) (conflicts with 1 and 4)
4 - light and thin wire (conflicts with 2 and 3)
5 - no reflexions (i.e. enough losses to prevent pulse ringing even when
totally lacking impedance matching at both ends)
6 - high bandwidth (conflicts 1,4,5)
7 - good insulation (500Vpk or more ac)
8 - durability

As you can see it is not so simple. By the time you produce something like
this that works for 1 year or more in a lab environment day by day use
(probably more than 30000 uses and 60000 flexures) it tends to cost money.

Peter

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