B o o k Reviews PROCEEDINGS OF THE FOURTH NATIONAL CONFERENCE ON TUBE TECHNIQUES. New York University Press, New York, 1959. 270 pp. Price 87.50. THIS paper-backed volume contains a wealth of specialized information on recent work in the field of electron tube manufacture and testing. The subject matter of the papers included is given in the following list. Where the actual title of the paper is quoted it is in inverted commas. For the sake of brevity, authors' names are omitted.
27. " Surface resistivity of metals and dielectric-metal j o i n t s " , especially in relation to the problem of providing a vacuum tight aperture for microwave power generators through which energy is conveyed from inside the tube to the external transmission system. 28. Critical review of properties of pure rhenium, tungstenrhenium and molybdenum-rhenium alloys and their uses in electron tubes (12 refs.). 29. Effect of nuclear radiation (neutrons, gamma-rays etc.) on glass (6 refs.).
1. An up-to-date account of flash and bulk getters (35 refs.). 2. The development of cold field-emission cathodes and the ultra high vacuum techniques employed (chiefly, titanium gettering) (5 refs.). 3. Electroformed ceramic-to-metal seals for an external circuit travelling-wave tube (1 ref.). 4a and 4b. Abstracts of papers on ceramic-metal sealing. 5. A quasi-optical seal for the open funnel end of a large (up to 36 in.) television cathode ray tube. 6. Improving glass-to-metal seal resistance to high humidity deterioration. 7. " A U H F metal-ceramic planar tetrode ". 8. " Temperature limitation of planar grids ". 9. The reduction of grid emission. 10. Coolants for high power tubes. 11. Brazing tungsten to molybdenum. 12. " Brazing by diffusion-controlled formation of a liquid intermediate phase " ; the object being to perform the braze at as low a temperature as possible. 13. A shaker for component evaluation of electron tubes. 14. An adjustable chuck for a glass-blowing lathe. 15. An optical system for the production of phosphor screens for colour television cathode ray tubes. 16. A review of European microwave tube techniques, including aspects of vacuum technology (I 18 refs.). 17. The production of fine complicated patterns by vacuum deposition methods in the development of the vidicon--a colour television pick-up tube. 18. Electron guns for travelling wave tubes. 19. Use of infra-red photography to measure cathode temperature. 20. Practical studies of sublimation from electron tube cathodes (2 refs.). 21. " T h e R.F. modulated field emission cathode as a harmonic generator ". 22. The use of the field-emission cathode in a two-cavity microwave amplifier. 23. " A noise display machine for studying cathode properties ". 24. Properties of the primary electron emitter consisting of a layer of porous magnesium oxide on a nickel base at room temperature. 25. " Secondary emission from MgO films and crystals" (7 refs.). 26. Production of the new materials, copper-base Aliron and copper-cored Aliron, for tube anodes.
" Means of reducing sublimation from base m e t a l s " .
31. " The effect of exhaust procedures upon the thermionicemission qualities of nickel cathode alloys ". 32. Account of dispenser cathodes, defined as cathodes that gain " electron emissive power by virtue of material dispensed on " their surfaces (31 refs.). 33.
" Thorium impregnated matrix cathode ".
Abstract of paper on refractory matrix cathode.
35. " The effect of calcium in thoriated-tungsten filaments on e m i s s i o n " ; a higher calcium content improves the drawing properties of the wire but causes slumped emission during life. 36. Relation between performance of a thermionic emitter and ambient gases surrounding it. 37. " Dynamic equilibrium processes in oxide-coated cathodes " ; a study of the factors which contribute to the production and destruction of donors (6 refs.). 38. Measurement of cathode interface impedance by pulse and sine-wave techniques. 39. Determination of the resistance and capacitance of an oxide coating on a thermionic cathode by ultra-high frequency measurements (3 refs.). 40.
" Interface resistance--it can be controlled " !
41. Abstract of paper on the measurement of cathode interface impedance. 42.
" Field emission in image tube ".
43. " Determination of vacuum-tube catastrophic wear-out failure properties from life-testing data ".
44. An all-quartz microbalance for use in vacuum to study mass changes in electron tube electrodes which occur, e.g. due to cathode sublimation, gas sorption (2 refs.). 45. Measurement of motion of grid wires in U H F planar triodes. 46. Grid emission in power tubes (abstract). The text is well printed, most of the line drawings are excellent, the photographic illustrations are generally good considering that they are within the text and not on selected paper. The high technical level of the papers cannot be doubted. Some of them exhibit the staccato style popular in America ; unfortunately, it does not lead to smooth reading ; one or two papers exhort the reader to follow the practice recommended to such an extent that they read almost like electioneering propaganda ! However, this no doubt indicates the outstanding vigour of the American electron tube industry. J. YARWOOD