The Logical Design of the Raytheon

results in output pulses of different amplitudes, it is possible, by mixing a constant-amplitude negative pulse in the video amplifier, to obtain as a final result a positive pulse for a positive element and a negative pulse for a negative element of the target. A developmental model of the Memory Tube intended for computer use is shown in Fig. 3. The general shape of the tube, the relative position of the guns and screen-and-target structure can be seen. Since the computer Memory Tube is still in the development stage, it is expected that many improvements in the design of both the tube and the associated circuits will be made before a completely satisfactory performance is achieved. It is hoped that the above brief account of the present state of development will stimulate workers in this field to explore further the potentialities of the memory device which has been made available to them. Andrew V. Haeff Naval Research Laboratory Washington, D. C.