A NEW FRANE GRID THAT IMPROVES ELEC'J'RON TUBE UNIFORMITY

Richard C. White and Robert E. Booth (Sylvania Electric Products, Inc.)

This paper describes the construction and fabricat ion of a new frame gr id f o r electron tubes which is adaptable to automatic production techniques a t a r a t e and cost comparable t o conventional siderod grids. It is shown a lso tha t these con- struction techniques produce a gr id that provides for tubes having greater relia- b i l i ty in such features as improved uniformity of e l ec t r i ca l cha rac t e r i s t i c s from

frame g r i d is par t icular ly appl icable to high performance tubes since the rigid frame Pe

AND IS ADAPTABLE TO AUTOMATIC FRO DUCT ION^

t o tube, and a b i l i t y to withstand severe mechanical shocks and vibrations. The

dts construction of a rugged grid with extremely small l a te ra l wi res .

THE NATURE AND PREYEXITON OF K " - A L N E MALFUNCTION IN TR TUBES

John D . H a l l and Paul E . Gates (Sylvania Electric Products, Inc. )

An investigation has been made t o determine the causes of permanent and tran- sient failures of keep-dive e lectrodes in TR tubes. Such fai lures are important since they cause crystal burnouts and system fa i lu re s , and have been a s ign i f i can t f ac to r i n the non-reliabil i ty of operating systems.

I n this invest igat ion, the primary emphasis was placed on both the keep-alive material and the keep-alive discharge characteristics. It was found t h a t conven- t iona l materids sputtered, building up deposits on the anode area causing shorts bebeen the keep-alive and the anode, or the material oxidized, the oxidized material creating an insulat ing barrier which caused the keep-alive voltage to increase,resul- ting i n a decrease i n the keep-alive current. In either case, the keep-alive became ineffective, and crystal burnout resulted.

A design has been developed which uses an electrode of semi-conductive t i t a n i a . With the use of t h i s material, and by operating with the proper discharge charac- teristics, keep-dives are now free from the above phenomena and they give both longer Ufe and improved tube characterist ics during life .

NUCLEAR RADIATION COUF4TER TUBES Ernest H. Wakef ield (Radiation Counter Laboratories, Inc . )

Nuclear radiat ion can be readily detected by counters operating i n the pro- portional. region. While the use of this region has unt i l recent ly been unappreciated, it has now become well known and i s regularly used for detecting alpha, beta, gamma, neutron and proton radiation. As a frame of reference, seven different present-day radiation sensing elements are discussed i n which the advantages and disadvantages of each are cited. The theory of proportional counters is presented. A br ie f mention is made of necessary electronic circuits. In addition, several specific uses of propor- t i o n a l counters are cited. In conclusion, it might be s ta ted that the counters ope- rating in the proportional region have as advantages: a speed of operation limited Only by the electronic circuit ; an abi l i ty to discr iminate between radiat ions of different energies; am excellent operating characteristic curve; a re la t ive ly g rea t tolerance t o a i r contamination. The detection of nuclear radiation in a gas counter operating in the proportional region, it is s a f e t o say, w i l l be widely used i n this Atomic Age.

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The development of the frame gr id was accomplished under U. S. Navy Contract. The Success of t h i s p ro j ec t was substantially aided by the far-sighted cooperation received from the above eency throyghout the development program.

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