Radio Standards Go to War*HAROLD P. WESTMANt, MEMBER, I.R.E.

Summary-World War I clearly demonstrated the economieswhich engineering standards provide. To obtain such benefits inthe radio field at this time, the War Committee on Radio is de-veloping, under the war procedure of the American StandardsAssociation, standards for radio components. The wartime andpeacetime procedures of preparing standards are described.

To be most useful, single designs of components must bechosen which are suitable for all military and naval conditionswhich may be met all over the world, and each part must carryunchanged its own identification number throughout all of thebranches of the Armed Services. These standards must not onlygive complete instructions to the manufacturer who produces thecomponent but must also provide the equipment design engineerwith all the data he needs.

To permit the inspection of components by personnel withsharply limited engineering knowledge, the standards are writtenin simple language and mathematics and other complexities areavoided.

0ORLD WAR I introduced standards into\\/\/manv fields that had not previously been in-

terested in them and extended and intensifiedtheir application in numerous other industries. In fact,that conflict undoubtedly did more to establish thevalue of standards as an effective method of increasingproduction and reducing waste of both materials andman-hours of labor than any other single event. It isnot strange, therefore, that another war should callupon the standards mechanism for assistance in pro-ducing the implements of its trade.The interlude of peace between these two world-

wide conflicts has provided a period of consolidation ofthe type that men seem to need between spurts of highactivity. In this peacetime interval, much has beenlearned of methods of developing standards, of makingtheir availability known to those who should be in-terested, and of putting them in operation effectivelyand with least upset to existing systems. We are, ac-cordingly, in an excellent position to do a fine pieceof standardizing at this time.

Radio, being a relatively young engineering field, hasbenefited from standardization for a substantial num-ber of its years. Engineering standards' exclusively onradio were first published in this country about thirtyyears ago. Manufacturing standards2 were developedlater as a result of the problems of supplying broadcastreceiving apparatus to the public. Both types of stand-

* Decimal classification: R200XR560. Original manuscript re-ceived by the Institute, January 25, 1943. Presented, Winter Con-ference, New York, N. Y., January 28, 1943.

t Secretary, War Committee on Radio, American StandardsAssociation, New York, N. Y.

1 Preliminary Report of the Committee on Standardization ofthe Institute of Radio Engineers, Inc., September 10, 1913.

2 Issued by The Association of Manufacturers of Electrical Sup-plies in September, 1924, and continued by the National ElectricalManufacturers Association to August, 1928. Succeeding manu-facturers standards were published by the Radio ManufacturersAssociation starting March 1, 1929.

ards have been continuously developed and effectivelyapplied since their introduction.These peacetime standards may be divided into four

classes: (a) definitions of technical terms; (b) letterand graphical symbols; (c) methods of testing andrating components and equipment; and (d) physicaldimensions. Because theory must precede practice-itwould be difficult to make something without thinkingabout it first-the earliest standards leaned heavilytowards the defining of terms. This has continued to bean essential study, for if we do not speak the samelanguage we might just as well not speak.

Letter and graphical symbols may well be consideredthe shorthand of terminology and their standardizationfollows logically. These first two classes get little if anyattention during war and may be considered primarilyas peacetime projects.

In contrast to peacetime requirements, wartimeplaces most emphasis on physical equipment. Althoughno belligerent dares give up research on the assumptionthat the war will last too short a time to permit itsfruits to lead the way to victory, nevertheless, wartimeis production time, in earnest, and the wheels of in-dustry must spin fast and purposefully. Each day'sbattle is fought with the things at hand regardless oftheir limitations and not with those which are beingdesigned or conceived, however excellent and effectivethey will be at some future date.

Furthermore, peacetime standards have anotherlimitation which cannot be tolerated during war. Theyignore the differences in material and labor costsamong the various manufacturers, depending on salesand advertising mechanisms to adjust selling pricesand keep the more expensively manufactured producton the market and its fabricator in business. There canbe only one economy in wartime. Each item must beproduced in the shortest time with the least expendi-ture of materials and manpower.Approximately three months after this country was

precipitated into the war, S. K. Wolf, of the Radioand Radar Division of the War Production Board, ar-ranged through the American Standards Associationfor a conference which resulted in the establishmentof the War Committee on Radio of which he is chair-man.The War Committee on Radio does not operate

under the same procedure as the Sectional Committeeon Radio which, since 1923, has been responsible forpeacetime radio standards. The Sectional Committeeis comprised of representatives of the manufacturersand consumers actively interested in the radio field.Its subcommittees are similarly representative and areresponsible for preparing drafts of proposed standards.

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It is the function of the Sectional Committee to becertain that, in the preparation of standards, all view-points are obtained and given adequate consideration.The drafts which are accepted by the Sectional Com-mittee are next examined by the sponsor, The Instituteof Radio Engineers, to ascertain that both the proce-dure of developing the proposed standard and itstechnical contents are satisfactory. The ElectricalStandards Committee of the American Standards As-sociation then reviews the procedure and if it is ap-proved, recommends the adoption of the standard tothe Standards Council where final validating actionoccurs. This is an exceedingly thorough process whichguarantees that all minorities are protected. It re-quires a substantial amount of time and is, therefore,not strictly suitable for a wartime program.The War Committee on Radio, which is charged

with preparing standards for radio components foruse in equipment for our Armed Services, consists of agroup of individuals who are skilled in the productionprocesses and requirements for such radio equipment.They are not chosen as representatives of any organiza-tion in this field. This permits them to vote on pro-posed standards as individuals and saves much timethat would be required in referring proposals back tolarge organizations which must search their internalstructures for comments and criticisms.The War Committee selects relatively small task

groups or drafting committees which are charged withthe responsibility of preparing the proposed standards.Usually a series of drafts are made, each based oncriticisms of a previous one. As each draft is completedit is sent to all known interested groups and individualswith requests for comments. The last draft is circu-lated in printed form and is made as nearly like the finalcopy as knowledge at that stage of the work permits.A meeting of the task group is then held to make all

final changes prompted by the criticisms submittedand the document in its revised form as approved bythe task group is sent to the War Committee on Radiofor ballot. After approval by the War Committeefinal action of adoption is taken in behalf of the Stand-ards Council by the Chairman of that body on therecommendation of the Electrical Standards Com-mittee.A few weeks after the War Committee on Radio was

set up and its personnel established, a second meetingwas held and a project to draft purchase specificationsfor fixed mica-dielectric capacitors was initiated. Thiswas to be a "guinea pig" to test the possibilities ofdoing a successful job and of developing a workableprocedure.

Strangely enough, one of the most time-consumingproblems did not concern technical design or manu-facture. Each branch of the Services identifies its radioequipment and component parts by a code group ofletters and numbers. This permits bookkeeping, in-ventory, and other records to be kept of the apparatus.

For a component to be interchangeable among alIbranches of the Armed Services, it must be identifiedIin all of them by the same code designation. A changelike this may seem simple but when it is applied tothousands of components it is not insignificant. How-ever, our Armed Services were willing to accept theconfusion and possibilities for error which a change ofthis kind inevitably brings and the development of anew identification system was undertaken.As a result of much consideration, a system was

evolved which is applicable to all components. It corn-sists of alternate groups of letters and numbers andfollows a definite pattern in which the differences be-tween the components are indicated successively fromthe coarsest to the finest. Thus, the first two lettersindicate the kind of component, such as a fixed mica-dielectric capacitor, a variable composition resistor, or asteatite standoff insulator. The next numbers identifythe drawing which establishes the physical size of theunit. The variations within these groups are then in-dicated in finer and finer steps by means of the succeed-ing code groups. No two parts having significant engi-neering differences may carry the same designation. Toavoid possible errors in handwriting or telegraphicmessages ordering replacement parts, the four letters,I, 0, Q, and Z are not used as they may be confusedwith numbers.When it was evident that the work on fixed mica-

dielectric capacitors showed excellent prospects of asuccessful conclusion, another meeting of the WarCommittee on Radio was held and a comprehensiveprogram was inaugurated.The following subjects are now on the agenda of the

War Committee.

(a) ComponentsConnectorsCrystals and HoldersDry BatteriesDynamotorsFixed CapacitorsFixed ResistorsTube SocketsVariable ResistorsVibrators

(b) MaterialsInsulating Materials

(c) ProcessesMetallic Surface CoatingsOrganic Surface CoatingsSoldering

The objective of the program is to produce a seriesof specifications which provide a range of componentssuitable for practically all normal designs of radio-and-electronic equipment for use by the Armed Services.These specifications must cover all the significantphysical and electrical requirements of each compo-nent and the necessary tests to insure that they aresuitable for the services to which they may be applied.No further technical data should be required by eitherthe manufacturer of the component or the equipmentdesign engineer. The components must be suitable foroperation at any place on the surface of the earth, orabove it.

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Further factors that are desired include (a) inter-changeability among all branches of the Armed Serv-ices, (b) increased production, (c) reduced wastage ofmaterials, critical or otherwise, (d) conservation oflabor time, and (e) clarity of presentation to avoidunnecessary difficulties between manufacturing andinspection personnel.The tremendous importance of radio in this war has

increased the demand for experienced personnel to thepoint where the supply is hopelessly inadequate. Thisforces the utilization of nonengineering personnel inall positions where a brief training period will developreasonably adequate abilities. The inspection of radiocomponents to see that they comply with the purchasespecifications is one service in which relatively un-trained personnel can be utilized. It is anticipated thatin the near future many of our government inspectorswill be girls having general high-school educations anda couple of months' intensive training in the inspectionof some particular component.Under these conditions, specifications must be simply

and clearly phrased. While this does not outlaw the useof technical terms, they should not be employed un-necessarily nor should they be overly complex. Simplelanguage is vastly to be preferred to that which "makesan impression."

Formulas should be avoided if at all possible. Oftenthey may be replaced by simple graphs or even bytables where the number of factors under considerationis not too large. Where formulas must be used, theyshould be reduced to the simplest form and care takento define all terms fully, including the units of meas-urement. So far as possible, common units such asinches and pounds, should be used instead of centi-meters and grams.Almost all components are tested over various ranges

of temperature. Industrial thermometers which arefound in the field may be calibrated for either theFahrenheit or centigrade systems. This requires thatall temperatures be designated in both values and it isunwise to depend on a conversion table to which ref-erence will have to be made while reading a test pro-cedure. It is much better to give both readings byputting one in parentheses after the other.

It must always be kept in mind that the inspectorwill probably not be an engineer and, therefore, cannotbe expected to use engineering judgement. When a listof tests is given to determine the goodness of the prod-uct, the number of failures permitted without penaltyto the manufacturer must be clearly shown. If toomany failures occur, the inspector should be instructedas to the next step. It should not be left to the inspectorto decide whether (a) to reject the actual componentswhich failed, (b) complain to the foreman of the pro-duction line, (c) search through the manufacturingprocesses for the cause of the failures, or (d) shut downthe whole production line.

Fortunately, we may expect the qualification tests,

which are performed to prove the effectiveness of theoriginal design, to be made by engineers or under theimmediate direction of an engineer. These tests areextremely thorough and rigorous. They include lifetesting and therefore require many days for theircompletion.

In view of the many new manufacturers who havelimited or no experience in this field of production, thespecifications go beyond qualification and productiontests. Definite tests are required at regular intervals ofproduction to provide reasonably thorough checks onthe entire manufacturing system. These production-sampling tests are made under the observance andauthority of the government inspector. A manu-facturer does not have the right to engage in an un-economical process which wastes materials and man-power simply because he may still be able to meet hisproduction quotas. If his production sampling showstoo large a rejection percentage, he must stop his pro-duction line until the trouble has been located andremedied.

Tests should be based on the performance of thecomponent and not on its materials or constructionalfeatures. This gives the designer the widest possiblelatitude and avoids modification of the test methods orrequirements if some materials become unavailable ata future time. Provisions for substitute materials arealways included and acceptance is based on a qualifica-tion test to prove that the substitute material is ade-quate for its purpose.

In peacetime, uneconomical designs often resultfrom fancied or real necessities on the part of the equip-ment designers. In an attempt to reduce the size andweight of a unit, the designer may demand, let us say,a higher capacitance in a given molded case than hasbeen available previously. This results in a capacitorstack which is so large that there is insufficient moldingmaterial around it to hold it firmly and thereby main-tain its value constant, or the slight amount of tippingwhich may occur in the molding process may exposethe stack and ruin the capacitor. It is conceivable tomanufacture such units with shrinkages of 50 or 60per cent, provided someone wants the good ones suf-ficiently to pay as well for the rejects. However, withmica on the critical list, we cannot afford to throw anyof it away and if a designer needs such a unit so greatlythat he cannot do without it, it should be ordered as aspecial design and not be included among the standardvalues. If it were made standard simply because itcould be manufactured and was needed for a small partof the total production, it is certain that most designersin choosing a by-pass or blocking capacitor of a givenphysical size would automatically pick the largestcapacitance value on the list on the theory that itcannot be too large but it can be too small. This wouldtend to concentrate production on the most uneco-nomical sizes.

Dimensional standards to secure interchangeability

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are thought of in peacetime as primarily a benefit tothe ultimate consumer. While this is a vital factorunder war conditions, the benefit goes much further.A manufacturer who is building equipment for severalbranches of the Armed Services, may require manythousand components of a given size on one productionschedule and a few dozen for another. He could notpreviously combine the orders to the parts manu-facturer because the type numbers were not the sameand there might be other subtle differences. Unifiedprocurement specifications will clarify this situationto the benefit of everyone concerned.Every effort is being made to develop specifications

for components which are suitable for operation any-where on the surface of the earth, below the sea, or inthe sky above. This is a global war and our fightingforces will be found in every climate. Any componentwhich is limited to one extreme service, as in the arcticor the tropics, presents a serious problem. It requiresthat the piece of equipment and spare parts be ear-marked for that particular climate. If changes in thecourse of the war demand unanticipated concentra-tions in some other climate, the equipment cannot bediverted there without the delay of replacing the com-ponents which are unsuited for the new destination.Information on the placement of substantial orders forapparatus for a certain climate would be extremelyvaluable to the enemy who would be forewarned ofthings to come.A next logical step to the adoption by the Armed

Services of common purchase specifications for radiocomponents would be a unified system of inspectionand qualification testing. It is recognized that thereare numerous difficulties in setting up such a systembut it is questioned whether any of these offer prob-lems as complex and extensive as the acceptance of the

new numbering system. The advantages of dealingwith a single responsible and authoritative laboratoryon any given component are manifold and compellingfrom the viewpoint of both the Armed Services andindustry.

All war standards expire when peace arrives. This,and the fact that military requirements are very dif-ferent from those for the civilian, has permitted theproblems of war standards to be viewed without anystrong commercial bias on the part of component andapparatus manufacturers. It is almost certain thatlittle or no military radio equipment will be orderedfor a substantial time after the cessation of hostilities.Thus, there will be no postwar military market todivide but, rather, a complete shift to civilian radioproducts.The existence of several billion dollars worth of

equipment throughout the various branches of theArmed Services, bearing common type numbers andbuilt under specifications which are the product of thecountry's most experienced engineers, will do much tocontinue these standards in operation. This gives riseto the hope that we shall never again be caught withsuch a variety of "standards" as to be essentially with-out any.The function of the American Standards Association

in this program is to provide the rules, guidance, andsecretarial assistance. None of these, nor all three, canof themselves produce standards. The outstanding co-operation of the three major groups, the Armed Serv-ices, the equipment manufacturers, and the componentsuppliers has made possible the extensive results whichhave already been achieved. They give promise of afulfilled schedule in the near future which should domuch for that early and victorious peace which is sodesired by us all.

Corrections

There has been brought to the attention of theeditors by the author, on the suggestion of a reader ofthe corresponding paper, an error in equation (6) ofGeorge F. Levy's paper, "Loop Antennas for Aircraft,"which appeared on pages 56-67 of the February, 1943,issue of the PROCEEDINGS. This equation should read

- 1(Ro + jwLo)

1CTZ = -

WC

E. H. Schulz, on the suggestion of a reader of hispaper, "Comparison of Voltage- and Current-Feed-back Amplifiers," which appeared on pages 25 to 28of the January, 1943, issue of the PROCEEDINGS, hascalled the attention of the Editor to the followingcorrections:

In equation (3) Zi should be replaced by ViIn equations (5) and (6) a minus sign should be

placed in front of ,u.In the sentence following equation (4) Vi should be

replaced by Vi.

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