843 
limitations imposed by the steady-state frequoncy response characteristics 
of the other components of the overall recording system. 
Steady-State Response Measurements. 
Wie Measurements were made using one coaxial line of a 955 - foot 
length of the special Simplex twin coaxial polyethylene cable for comparison 
with the calculated curves of Plates 2, 3, 4 and 5. Plate 6 is typical of 
the results obtained. 
The input signal ve wes taken from a cathode-follower output 
amplifier of low output resistance. The signal sources used to supply this 
amplifier were a General Radio Type 605-B Standard Signal Generator and a 
Hewlett Packard Model 200C Audio Oscillator. For the input capacity Cor, @ 
100 micromicrofarad capacitor was used to represent the piezoelectric gauge. 
The input voltage Vo and the output voltage Vy, were measured by a Hewlett 
Packard Model 400C VIVM. The input voltage Vo was held constant at 5 rms 
volts. The measured characteristic impedance of one of the twin coaxial 
lines of the cable was 50.4 ohms. The measured capacity of one of the 
coaxial lines was 30.46 micromicrofarads per foot. 
In Plate 6 the calculated curve was obtained by using Eq. (3). 
At the higher frequencies the calculated curve exhibits sharper resonance 
peaks of greater magnitude than those of the measured curve. This is 
because Eq. (3) was derived from the theory of an ideal cable in which the 
series resistance loss and the dielectric loss are neglected. When 
allowance is made for the attenuation resulting from these losses, the 
measured and calculated curves are in good agreement. 
Step-Transient Response Calculations 
8. Following the mathematical procedure developed in reference (a) 
it can be shown that for the network of Plate 1 the first two terms in the 
equation for the transient response to an applied step voltage Vo are 
= teRC . 
(4) cee = 2 e (1+k)mRc 
t+ = RC 
- t-3RC 
+ 2(k-1) e 1+k)mRC 1+ 2 : t-3RC) | + ... 
(16k) 2m (k-1) (isk) mRC 
t 2 3RC 
== NOLM 10467 
