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BELL SYSTEM TECHNICAL JOURNAL 



are used or not, always has more capacitance and inductance asso- 

 ciated with it than a single resistance of the same value. A certain 

 amount of compensation between the capacitance and inductance 

 may be effected by proper design, but it may be generally accepted 

 that the inductance of the wiring makes the phase angle of the low 



Fig. 3 — Resonance-type frequency meter 



resistance values comparatively high and the capacitance between 

 dials and between units of each dial makes the phase angle of the 

 high values comparatively high. This effect can only be overcome 

 by a compact design using coils of small physical size. This sets a 

 limitation on coils for use in dial boxes which is not present to such 

 an extent in the case of single resistance units or single value prime 

 standards. 



Methods of Measurement 



We have discussed already measurements of frequency and resistance 

 in connection with the description of standards, and we will not discuss 

 them further here. We are particularly concerned with the measure- 

 ment of impedance of all types, it being understood that an>- resistance 

 having a phase angle which is not negligible or which is of special 

 interest is to be considered a special type of impedance. 



