Only a few of the transfer functions, networks of which are well known, are used in the conventional synthesis through frequency response method, but in the synthesis through pole-zero configurations through statistical study, or in non-interaction of variables in multivariable system, the transfer function of compensation element is to be determined from the given specifications and transfer functions of the remaining elements. In each case, it is required to realize the transfer function with two-terminal pair network in the stage of designing. Since the principal interest is placed in the low frequency range including zero in the control system, circuit elements other than R and C can not be employed. This report refers to the synthesis of RC two-terminal pair network which will satisfy the prescribed transfer function. Also given in this report are general methods of synthesis with some examples.

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The method described in this paper is an application of “Dominant Roots Specifying Method” to Sampled-Data Control Systems. Roots Specifying method is a method to synthesize compensating networks to give a pair of roots specified as dominant roots for higher order system. This method is applied to the synthesis of the sampled data control systems, taking advantage of the fact that when both high order and 2 nd order sampled data control systems are approximate in response their responses will be similar each other even if their samplers and holders are removed. Therefore, the continuous feedback systems devised on the assumption that samplers and holders are removed from the sampled data control systems are compensated by simple continuous compensating networks so as to satisfy the given specifications. As, in synthesizing, the step response of the 2 nd order sampled data system has an important role in obtain ing some specifications (constant overshoot, actual angular velocity, etc.), the results of analysis by E. I. Jury are used. Compensating methods are described in general and an example is discussed. Results are checed by an analog computer. In conclusion, it is proved that this method is useful if the argument of the characteristic equation of sampled data control system in Z plane is smaller than 90°.

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When a differential transformer having a high linearity is designed, there are so many conditions to consider that it is very difficult to correctly induce overall conclusions with only a few experiments under particular conditions. This problem is solved in this paper as follows:
1) Differential transformers are divided into two classes, two sectional type and three sectional type.
2) Designing condition is decided for constant primary impedance on each type.
3) Secondary coil is reasonably arranged by checking magnetic flux distributions.
4) Linear range is extended by means of feedback compensation including the connected circuit.
Obtained through the above study are the excellent differential transformers suitable for many conditions and yet have such a wide linear range as 30-40% of their length.

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Described in this paper is a pneumatic micrometer which has a linear transfer characteristic over very wide range and operates with 1.0 kg/cm² source pressure. This instrument is composed of two single pneumatic amplifiers, one has a jet nozzle which is held by a spring-bellows negative feedback trans ducer and serves as a pre-amplifier for output circuit, the other is connected in cascade to the former through a pressure-displacement transducer and serves as an output amplifier. The transfer amplification factors are given as K^*/S when K^* is a spring constant of the spring-bellows transducer for feedback and S a bellows effective area of it. By employing a spring of an adequate constant, therefore, any amplifica tion can be easily obtained without changing the pneumatic circuit component. The experiment by using two spring assemblies which are composed of four compression springs, proved that 86 to 95% range of full scale is linearized with an accuracy of less than 1%. Response time has also been improved compared with the single pneumatic micrometer circuit which has a same out-put circuit as that of this cascade micrometer. Also discussed are the effects of changing the circuit component and dynamic performance.

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In general, the current running in thermistor thermometer is expressed as
I=R'-R/R+ZE/Z_∞
where R is the resistance of thermistor, E electromotive force of dry cell and R', Z, Z∞ being constant. By using the thermistor of low temperature coefficient, uniform temperature scale can be obtained. By connecting the thermistor element with suitable 4 terminal network of Π type or Τ type, thermistor of equal temperature resistance characteristics are obtained.

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