R 4  POTENTIOMETERS R 4.1 CONCEPTS AND DEFINITIONS Potentiometers are electromechanical components and therefore exposed not only to the weaknesses of fixed resistors but also to all the failure possibilities of electromechanics. The reliability is comparatively poor. It will be even lower if we try to tool the shafts for our own special applications!! The total resistance seldom is critical and usually follows the...

L.2. Equivalent Circuits and Simulation Models Modern measuring equipment, such as the HP4195A impedance analyzer and similar instruments, allow computer-aided derivation of equivalent circuits and their optimization. Constant parameters for inductance L, capacitance C and resistance R are required for the simulation of electronic circuits. An incorrect approach in defining an equivalent circuit leads to flawed or incorrect simulation results. Equivalent circuit parameters are...

C 2.2      PAPER CAPACITORS Under this headline we deal mainly with pure paper dielectrics. At the same time we ought to say that combinations of paper and plastic, i.e. mixed dielectrics, are rather common. C 2.2.1 Paper / foil The history of the commercial capacitor started with paper foil dielectrics and electrodes of aluminum foils. Because paper is porous it has to be impregnated...

R 3.7 CARBON FILM Carbon film resistors sometimes are called surface layer resistors. Better qualities are classified as “stable” with a ΔR/R that will stop at ≤1%. Their role has, to a great extent, been taken over by the metal film but they still have a market, especially as cheap 5 per cent E 24 components. At new designs one should yet consider replacing...

R 3 NON-WIREWOUND RESISTORS R 3.1 OVERVIEW Non-wirewound resistive elements may be produced and arranged in a lot of different ways. We shall present the following types, differentiated by constructional material or specific design: R 3.2                      Film resistors, in generalR 3.3                      Metal film / thin filmR 3.4                      Metal foilR 3.5                      Metal glaze/thick filmR 3.6                      Metal oxide /"metox"R 3.7                      Carbon filmR 3.8                      Carbon compositionR 3.9                     ...