Electronic analogue methods in X ray Crystallography

Abstract

Among the advantages of the structure factor computer described here are the following: (i) Use of standard components throughout, and very little wiring requirements, thus ensuring great ease in mass production. (ii) Very little mechanical construction (only the mounting of the relays and the indicator part require any mechanical work). (iii) Ease of operation and servicing. (iv) Unlimited range of indices and good accuracy in focusing of data. An accuracy of 0.01 of the cell edge is ample considering the inaccuracy that may be involved in the cosine or sine generation and series. The use of total digital and analogue methods has made a great simplicity in circuitry possible. The accuracy, of course, is more than that of a purely analogue machine, but less than that of a purely digital type of machine. In effect, the design enables one to get a closer approach to the accuracy of a digital computer while keeping the cost down at an analogue computer’s level.