ACCELERATION AND ITS INFLUENCE ON ELECTRON TUBES 1229 



Although, as a result of the trend to miniaturization, the strength of 

 electron tubes has been increased, due to the smaller size and mass of 

 elements employed, much has still to be done to increase tube resistance 

 to ballistic shock. This would result in simplification of shipping con- 

 tainers and reduce the need for protection by shock absorbers in equip- 

 ment. Equally important is the effort now made to reduce the micro- 

 phonic response of the tubes. Here, too, the smaller size of the late 

 tubes is of advantage because element resonant frequencies are increased. 

 And since the higher frequency components of disturbances are largely 

 attenuated by equipment structures, the tube responses have been 

 lessened. 



With a better understanding of the problems involved in tube pro- 

 tection, it is also quite possible that further improvements can be ef- 

 fected in some instances by structural changes of equipment members, 

 or re-orientation of tubes in the equipment to reduce the effects of shock 

 and vibrations on tubes. 



BIBLIOGRAPHY 



1. Shock and Vibration Instrumentation, NRL report #0-2645. 



2. Mechanical vibrations, Den Hartog, McGraw-Hill Book Co. 



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4. A Noise Free Instrument Cable, National Bureau of Standards, Technical 



News Bulletin, 36, No. 3. 



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Mfg. Co. report. New Techniques for Measuring Forces and Wear, W. P. 

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1945. 



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Corps Engineering Laboratories, Army Project No. 0302 A. 



9. MIL-E-IB, Military Specifications for Electron Tubes. 



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H. A. Lefkowitz, MM-45-2920-4. 



11. Shock Testing Mechanism for Electrical Indicating Instruments, ASA-C 39.3 



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Devices, I. Vigness, R. C. Novak and E. W. Kammer, NRL Report No. 

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