This will sound maybe stupid, but I'm amateur in electronics and I'm in process of learning :) I analysed till now some basic circuits involving opamps, diodes etc. Although some circuit looks simple (only few opamps, diodes, resistors, capacitors and source (sources)), mathematics that descriebe that simple circuit can be very complicated, especially if we want to calculate full response of circuit (not steady stade). I was wondering, how then some complicated electronics schematics are analysed? I mean there are devices contaning hundreds of components inside it, it would be impossible to apply some circuit analysis methods there (KCL, KVL etc), right? How important are those network analysing methods we are studying in school in practice (in repairing electrical devices)?