Abstract :
This paper has been written to correlate information relative to the manufacture of Quartz Crystals of the plated-electrode type. It is essential, to facilitate manufacture, that the various effects of plating upon frequency, activity and stability should be predictable. The first object of the paper is to develop a simple practical theory to account for and predetermine the frequency changes resultant upon varying amounts of plating. Closely associated with the design of electrodes and indeed inseparably linked, is the subject of clamping and mounting of the quartz plate. This is dealt with and reasons for selecting the location of clamping points are discussed at some length. Inferior plating is known to cause trouble, not merely immediately, but also over a long period. Some precautions to be observed in respect of plating quality are suggested. Throughout the paper the aim has been to provide information with a minimum amount of indirectly associated theory. The extension of the theory not only to sputtering of gold, but also to the electro-plating method, increases its value and enables an extremely fine adjustment of frequency to be made.
