Internet search unfriendly...but common sense rules..."metodou" is easy to leave out because it's clear it's a method...leave out for sake of uncluttered language....................I'd use pipe property scanning methods alternatively but that seems "too" technical...it's allowed to be "English" too :) Engineers have their noses buried in their work, but this would make sense to any of them...

Using as a starting point:
“Oscilografické snímání charakteristiky germaniových diod (Dr Helmar Frank)”
http://www.volny.cz/pjenicek/radioprevzate/casopisy/st54_1o....

I arrived at:
“Oscillographic methods of recording tube characteristics are also useful in detecting and portraying anomalous features of tube behavior that would be difficult or impossible to detect from static point-by-point measurements.”
http://www.djmurat.biz.archive.org/stream/ElectronicMeasurem...

and various related examples:
“Oscillographic Method of Measuring Positive-Grid Characteristics… In testing large high-vacuum tubes it is difficult to take positive-grid characteristic data using ordinary voltmeters and ammeters since the heat dissipated would destroy the tube”
http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=168717...