Since I've got a Digital Multimeter that can measure capacitance, I should try measuring the capacitance/m of the Response WB-1530 cable I buy from my local Jaycar Electronics store, would be interesting to see what result/s I get, I think I've got a 1m length spare somewhere.
For those of you who want to know, a capacitor is formed whenever we have two conductors that are close together, but separated by some kind of insulation material, in the case of shielded cabling used to make instrument leads, we have two conductors, the inner core and the outer braid shielding, and an insulator, the plastic covering of the inner cores.
Okay, I've just tried measuring the capacitance of 1m of Jaycar Electronics WB-1530 cable, with my Digital Multimeter set to the 20nF range, I got a reading of 0.39nF (390pF), next I disconnected the two probes from the cable and measured how much capacitance the meter probes were contributing to the result, it turned out to be 0.06nF (60pF), if I take 60pF away from 390pF, that gives us a total of 330pF/m (with both of the inner cores connected together).
Bit of trivia, the basic unit of capacitance is called the "Farad", it was named after Michael Faraday, a famous British scientist and physicist, now the Farad is a very large unit of capacitance, a bit too large for practical use in Electronics but there are 1 Farad capacitors available, the Farad can be broken down into smaller units of capacitance:
1 Farad = 1000 mili-Farads.
1 mili-Farad = 1000 micro-Farads.
1 micro-Farad = 1000 nano-Farads.
1 nano-Farad = 1000 pico-Farads.
Last edited by DrNomis_44; 28-02-2018 at 09:27 PM.
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