The Tacitron, A Low Noise Thyratron Capable of Current Interruption by Grid Action

Two thyratron considerations are (1) spurious noise output, and (2) speed and ease with which the anode current can be tuned on and off. The spurious noise output of conventional thyratrons often is such that they cannot be operated close to sensitive communications equipment. In addition, while the anode current can be established in a fraction of a microsecond, current interruption often requires times of the order of 100 microseconds. During this time one is confronted with the additional disadvantage of having to remove the anode voltage. The tacitron, a new thyratron whose construction and operation are herein described and analyzed, is so quiet in operation that it can be operated in close proximity to sensitive communications equipment without noticeable interference. Furthermore, its anode current can be switched on or off in about one microsecond without the necessity of anode voltage removal. With respect to arc drop, over-all efficiency, tube construction, and other salient characteristics the tube is similar to conventional ones. The tacitron owes its unusual capabilities mainly to a grid design that insures tube operation in a unique discharge mode where in ion generation takes place solely in the grid-anode region. Besides being useful in applications in which conventional thyratrons are now used, this new tube offers the possibility of use in many new applications presently denied conventional thyratrons, either because of noise or recovery time considerations. This includes computers and all sorts of pulse circuits.