EDITORIALffiruET$ffisAl COpycsPY

UNIVERSITYUNIVERSITY OF OF MINNESOTAI\4INMSOTA ST.ST. ANTHONYANTHONY FALLS FAttS HYDRAULICHYDRAUTIC LABORATORYTABORATORY LORENZTORENZ G.G. STRAUB.STRAUB, DirectorDirector

TechnicalTechnicql PaperPaper No. No. 23.23, Series Series BB

TheThe SonicSonic Surface-Surface-WaveWave TransducerTransducer

/ Preprint of Paper toto be Presented atct the AmericanAmericcn Towing Tank Conference.Conference, University of California. California, Berkeley Campus.Ccmrpus, AugustAugiust 31 to September 2.2, 1959

by JOHN]OHN M. KILLENKNffiN

JulyJuly 19591959 Minnecpolis,Minneapolis. IvlinnesolcrMinnesota

/ :' UNIVERSITYUNIVERSITY OFOF MINNESOTA MINMSOTA ST.ST. ANTHONYAIiITHONY FALLSFALTS HYDRAULICHYDNAUTIC LABORATORY TABONATORY LORENZtOnENZ G.G. STRAUB,STRAIJB, DirectorDirector

TechnicalTechniccl PaperPcrper NoNo.. 23,23, SeriesSeries BB

The SonicSonic Surface-Surface-\MaveWave TransducerTransducer

Preprint of Paper Pcper to be Presented atctt the AmericanAmericcn Towing TankTc"'L Conference, University of California,Cclifornio Berkeley Campus,Ccmpus, August 313l to September 2, 1959lg59

by JOHNIOIIN MM.. KILLENKILI.EN

•

IulyJuly 1959 Minnecrpolis,Minneapolis, MinnesotcMinnesota ..

ABSTRACTastISagS

AA wavewave height measuringmeasuring instrument instn:ment isis described described. whichwhieh measuresmeasures thethe height ofof waterwater surfacesurface waveswanes byb;r means ofof aa sonicsonic rangingranging techniquetechnique inin airoair" This systemsystern isis advantageousadvantageous forfor wave amplitude measurementsmeasurernents fromfrom a movingnroving towingtow'ing carriage carriage since thethe sensing elementselenrents or itsi-ts supports zuppor.ls do not disturb thethe water surface.surface"

The?he design operating range of the instrumentinstn:nrent is 2-in.Z-in. to 2-ft wave height.height" The accuracy of measurement depends on the incrementalj-ncremental slope ofoJ the water surface srirface at the point of measurement.measurement," An intrinsic erroreror of !0.83O,B per centeent average over the wave would occur for a 2-ft2-fb wave with a slope at mid­nid- height of 0.2. This?his error emor increasesinereases to !3.2!3,2 per per cent for a 2-in. wave of the same slope.slope, The error is much reduced for both these cond.itionsconditions with less steep waves. rraves.

L11iii a {

------CONTENTSCONTENTS Page

Abstract.. e. . e r o o. e r o o ... r. ! . r r.. taaaa+4+iii Abstract •••••• • • • • • •• 0 • • • • • • • • • • • • • • • • tist of lllustrations List of Illustrations •n •o •. •. • ! ••• r, . •. • t • . • . • . •| •. •. • . • . •c •toaaav •••• v

I.T. INTRODUCTION fl{tnOSiCTlON •••. . . •...... ,. 0o •c •. •. •o •f •. •••I o e •r •r. • •. •. • o •.. • 11

II.rr" DESCRIPTIOND$scRrPTf0I{0FAPPAnA:Ils OF APPARATUS •r.. • • 0r. • ..o.,.. • .. • •r. • •o •o •o,*... ., • • • •' 1

III.III' ACCURACYAccUBAcT0FI{EAsUns}4s}illf OF MEASUREMENT •. •o.6... • • • • • •o... • • • •o. • '0 ••o.. • •e ..r. 0 2

fV" CIRCUIT CffiCUITOE$CHIPTI0I\T DESCRIPTION •" •o I • • • 0 • • • • • • • • • • 0 • • IV. •oo • 0 o r..o o. o,... c. + o.. 5 A. PulserFnlsgr 0o ~D 0o •.. • "40. .. • •ara{ • •• •a. • 0rr.., 0 • • " •r.... • • • • 5 B. ,.SparkSpark CoilCoLl and ard Gap .."..c .. . d ! 0 o •. .0 •. •. •. •o •. •I "o •. •{ •r 5) A C. MicrophoneHlerophorre ••••d o o r 0. 0o. ., • • •i! •c' 0' 0. •o, <> •o •o •* .. r 0o •o •. •. 6 D.D" Amplifierarrplifier and Amplitude^&raplitude Discriminatorlliscriminator ...... c . e,, . '" * ••. I 6 A E.E" Phantastron Delay. Delay o 04 .....* * r" ...o + 0a,, •r .,a

V. ACKNOWLEDGMENTS AC,K$0HLEDGMEHT$ '0 *, 0 .. .i!I"*tr{ 0n,r.}.+*.r, . • .. e' • .. '"$*a*+. ... • • ~ • !}. • •• }. • 7 a...

ListIrist of References Hefergnces ...... r + * € r + c oa

iviv ...

1&rqr 1ST ogg F ------MsgSSggrgrgI 1 1 U S T RAT ION S Figure Page

1 PhotographPhotographof of FrontFrontPanel Panel •... • • •r .0r' o ••r... • • 0r. • .. i,..,...... • • • • 11It

2 Photograph of RangingBanging Head o.o I 0o 00. o .•r 0 6 •. 0€ 0r •r •c' 0 •. •• ., •. 12L2 i =h0ft 3 LargeLargeMechani.calWave Mechanical Wave HH*2ft, 1& 2 ft, .>...\ 1& 40 ft .0.0.. c c o o .c .c. • 13 o = 4 Small$mall Mechanicallfiechanical Wave H 1& 2 in.,i-n., .>...\ = 2 ft •. •. •. •r • . •. • ., • 141I+

tr 5 Photographs of Towing Carriage and Mechanical}4echanical Waves •. •. 0o •. •, 15

6 Comparison of Capacitive Wave lfave Record Hecord with l,iith SonicSonie WaveHave Record, - = HI{ 1& 0.6930"693 ft, SteepnessSieepness - 0.055 •. 0 o 0. ••. + 0 . 0o •. 0., •••••. . . . 1615

7 Comparisonfionrpartson of CapacitiveCapaeitive Wave Have RecordBecord with r'rith Sonic Wavel{ave Record, Eeeord, -O.I25 HI{.Iftr • 1 ft, Steepness 1& 0.125 ••••••••••••••••.. s... r... *...., 17t7

8X Functional BlockHlock DiagramDiagran of Sonic$onic Wave-Profile !{ave-Profile Transducer •. •* 181B

9 MicrophoneHicrophone and PreamplifierPrearnplifier Housing .• • ., • •. o0 •{, •. •. o e 0 e 0q ••o, 19

10 FrequencyFrequencyResponse Response ofofPreamplifier Preamplifier ,•• o 0& •|, 0 •* •o •c.5 • 0 •r 0! 0r 204U

11 Pulser ••.. •r ·e*... • • • 0c. • •. •••••••••.. r r a.eaao...... 0 ••••••• 212A

12 Delayklay Phantastron and &aplitudeAmplitude Discriminatorliseriminator, • •o .• •c •. •c •. • . 22

13 AmplifiersA:aplifiers •••••••••" f . *.. * d r. '. + • c.. r• 0c e • , • •+ r • e 0 •r.... • • • • c• 23

14T4 Bootstrap$weepandHol-d:ingCircuitsBootstrap Sweep and Holding Circuits .• c• •s.., • • 0 c0 *.. • • • o• o 0 2b24

1r' 15L} PowgrSuppliesPower Supplies •••••••. r.6 r. I o.0 ••• r. {• !. • • c0 c • f • . • r • r. • • r}. • • 25z,

v THE $ON]C ------SURFACE-WAVESU&EAgg-ggsE------33g,rE!sqg&TRANSDUCER

I.1, INTRODUCTIONII{TNOAICTION

The use of a wave-profile $ave-profi:e recorder whoseerhose sensing elements ele$ent$ are sub­ su^b- mergednerged or partly submerged andand. which is mounted on a towing toring carriageearriage movingnoving at - high speed $peed produces problems of structural etrructural ssupport,upport of the element and dis­ dis- turbanceturbanee of the liquid surface.surfaee. The wave-profile recorder described in this thj"s reportreport' is based on the soI1;ic-rangingso4ic-ranging principle in air and appears tot,o overcomeovercms these difficultiesdiffleulties since sj-nce no part of the instrumenti:rstrunent contacts contaets the waterrrater surfacesurfaeeoo

The instrumentinst:rrment is intended to operate with rith wave heights of 2 in.in" to 2 ft,fL, wave lengths of 2 tota 40LO ft, and ad an flequivalentneqr::lvalent periodfiperiodlt as short as 1/20t/2O sec.$€cr These ?hese operatingoperati^agrang9s ranges aresre presunedpresumed to correspond eorrespond to ranges of interesti-nterrest ini-n laboratory wave studies andanddo do not specifyspecif) the limits of application.application, The ?he obt.ainableobtainable accuracyacfiracy is dependent on the incremental ineremental slope and thetbe waveuave heighto Therefore, withrr:th this instrument, i-nsLrnment, as withrrith mostr*ost ''plrysicalphysical measuring instruments, iastnments, , carefulcarefuJ- attention mustrnusb be paidpald to these two mentioned geometriesge*raetries in order to keep errorseruors within the acceptable limits ljm:its for the particular investigation.investigat'ion"

IIoII" DESCRIPTIONDBSCAIPTIO}d OF APPARATUSAPPASAfl]S

The instrumentj-nstnnent functionsfunciions as follows: fo3*lows: A S" veryve:y $ortshort pulse ofsf sound is transmittedtranrxrltted from froyn a point as close elose as pracbica1-practical to the water surface. The ?he sound puSsepulse is reflected reflLeeted by the water sater surface *rrfaee and sensed byW a microphonenicrophone lo­ 1o- cated as closeelose as possible tot,o the point of transmissiono transnrissiono Appropriate elec­elec- tronictronie circuits eircuiis measureReafirre the timetjrce ofef travel ofsf the soundsornrd pulse and convert this timetirne intolnts a voltage proportional to the time" tixe" When Hhen this process is repeatedrrepeated 120 times tjmes a second, seeond, a voltage output results whose r*hose magnitudenagritude varies withsith the changes in the levelIevel of the water surface" sarfaceo On a cathode-raycathede-ray oscillographoseillopraph or light-beamlight-bear* oscillographoscll1ograph which shich have trave a high-frequencyhlgh-frcquency response, thisthi-s wave$a?€ pro­pro* filefi1.e will appear composedconposed of a seriesserj.es ofcf small effalJ- steps,sLeps, eacheaeh step corresponding to a sample sanrple of the wave profile"profile o On0n most rnost direct-writingd:irect-writing oscillographs whose frequencyfrequeney responsere$povrse extendsexbends to about 10010O cycles, the wave profile willwiIL appear as a smoothgaooth line"line. 22

TheThe instrnrnentinstrument lsis composedcomposed pf of twotwo parts:parts: aa controlcontrol panel,panel, Fig.Fig. 1,1, andand aa rangingranging head,,head, Fig.Fig. 2,2. InIn prac*iealpractical applicationapplication thethe raagingranging headhead isis placedplaced appro:ci*ratepapproximately 5.55r5 in*in. frosrfrom thethe rnaxj:armmaximum erpectedexpected crestcrest ofof tbethe rrilsY€nrwaves. f;heThe rangingranging head.head sancan bebe attachedattached toto somesome positioningpositioning devicedevice forfor easeease ofof oper-oper­ ationation andand calibration.calibration.

AA $steppedt"stepped" rangerange controlcontrol onon thethe controlcontrol sectionsection panelpanel pemS"tspermits liJcelike adjust:nentadjustment ofof t,hethe systerosystem sensitivity forfor aa $avewave heightheight ofof 22 1n.in. toto 22 ft.

rrlIII. AcfiinaclACCURACY CIFOF $EA$gnE$fri\lTMEASUREMENT

The pulse of sor:ndsound em:ittedemitted Wby thethe tranenittertransmitter behaves as a spher5-ealspherical lirave.wave. As a result t,hethe apparatus measures the shorbestshortest distance frmfrom the trans-trans­ raLttermitter teto lhethe vaterwater surface and returrr.return. OaOn slotrlingsloping surfaces this shortest'shortest *istancedistance is to a paintpoint slightly displaced fronrfrom *ireetlydirectly belorbelow the transmitter. ?hisThis weuldwould not cause error if the psi.rrtpoint of reflection were kns!'ril,.known. It is usrr-usu­ a1lyally necessatynecessary tsto assweassume the reflection point is dj.rrectlydirectly belorbelow the trans-trans­ nltter;mitter; this produces a snallsmall error injn the above measureme$t.measurement.

If the transmittingtransn:itting spark and ttrethe microphonemicrophor:e diaphraurdiaphram are considered to be the ihe foci of an ellipse whichshich is tangent to the water surfacesr:rface at the point of reflection,reffection, the followingfo3-loring expressionexpressi-on for error can be developed fromfrcm • the optical optical- propertiesproperbies of the ellipse.el.lipse'

2 1/2 lOOr 1 c %error • (1)(r) H ( 2 2 ) 1 [ cos e 4r 1 4 !'YL<-'): i- '4 where r = measured distance (wave amplitude plus 5-1/2 in.) J . '~t HH == waveWaVe le-1€"rg€.thngth hi,i."t, t '7,:--n, I Cc =E separationseparation of of sparkspark andand microphonemi-erophone ee == angle alelgrii-irllTi;l of a tangent to the water surface atat tthehe ppoi-ut oint of reflection with thel;"tH#HJ"'*ce horizontal

T?hishis expression expression showsshoss anan upwardapward shiftshift of of thethe recorded reeorded crestqest andand troughtrough which shich isj-s notnot thethe same saare at at the the respectiverespective points,points, resultresultinging inin anan error error ini:r wavesave height height measurement. neasurerent. IfIf thethe separationseparation ofsf the the sparsparkk a andnd t transnitterr ansmittE;;r isis mademade sufficientlys!-fficiently small,sr*all, thisthis error error cancan bebe neglected r:eglected andard t thehe eextrlressioaxpression forfor perper centcent erroremor becomesbecomes 3'i

5a*sZ 5 - %fi error ervar %S (2)dzj H

s$ ..- the incrementalj-ncremental- slope of the watersater surfaces:rface at the tbe measuring point

As an example, consider thethe two t*ro extremes extrernes of waves withw:ith (1)til a height of 2 inin,.. and a length of 2 ft, andane (2) a heighttreight of 2 ft andasd a length of 40 l+0 ft. For the 2-ino 2-in. wave rn'ave, ~ Eq..Sq" (1){]-) showssh*rs an error in measuredgreasured'' height of 1/2%3-/2fi and an error errror ini-a amplitudeauplitude on the slope at mid-pointni-d-point of 700%7 "&o ..

The?he errorerrsr on theths 2-ft wave is:s 0 0"gL$onthemid-slope .. 94% on the mid-slope andand. negligibleneglig:lble on the crest..crest" When Shen the instrument i-ns'tnment has a relative r"elative motion with respect to the tle wave whose profile it is ls measuring.9 *reasuring" two additional sources of error ariseariseo .. Both these, theseu however.9 hoarever, produce a phase shiftshi-ft of the entire entir.e wave pattern in the direction of motion notion and therefore should not cause any argr greatgr"eat difficulty.diffi.culty"

First there willlri13- be a 'small smalL displacement of the record due to the finite velocity ve].ocity of propagation of the sound.. sound" With a maximumnaximr:m sound path ofsf 5 ftfb for . the 2-ft wavesave and ard. a carriage cariage speed of 202O fps,fps.9 there willTdIL be a shiftshj-ft - = of 0O"J-0 1 ft. For Fsr A}. .. 22o8t0 0, and H" II 2 in.,~ in", there would be a phase shiftskift of

11"8 .. 8 dedegrneesgrees at the troughs and 00.015 .. 016 ft or 0 0"30 3 degrees aa*rt,.. thetbe crests. crests,

The?he second eausecause of phase shift is due to sampling and filteringo filter{-ng" The?he filteringf,ilteri-ng actionactlon ofaf tbethe vecorderrecorder system onen the "stepped"Psteppedn output of the soniceonic wave transducer*mnsducer results in a time tixe delay whichshich canean be as great &$as one­orl€- lralfhalf the sampling period.period [1][1J.*' 0-'* UnderUnd,er the assrrnptionofassumption of a constant delay de1-ayu 9 the wave profil-esprofiles at variousqarious velosittes'werevelocities were delayed ini:r proporfionprpportion to a csnstantconstant ra*tipliedmultiplied by velocity at each poi:ntopointa

fbeThe eonbinedcombined effect of al"Lall the errors meationedmentioned is shown i-ain Figs"Figs. 3 and.and l+.4. ?heseThese are experS-rnentalexperinient al poi:rtspoints enon tsotwo $aveswaves eonsbnrctedconstructed of sheet metaS-metal trithwith a trochoida}trochoidal slrapeshape w:ithwith di-menslonsdimensions inilicaiedindicated enon th*t he figr:res"figures o ?heThe sheet-sheet­ metal t*ayesrtrhiJ-ewaves, while orrlyapproxi-raati::gasaterwaye,only approximating a water wave, harehave the adx-ar:tageadvantage of pos-pos­ sessingseSSing an easily aeasurablemeasurable slope and height at argrany point and consequently

*Idl*bu*u *Numbers in brackets veferrefer to the eorrespond:i:rgcorresponding nr*abersnumbers in the List cfof EefereneesReferences snon po B.8. I+4 areare nsefuluseful forfor eva-luatingevaluating thethe behaviorbehavior ofof thethe r,reasuringmeasuring device.device. ?heThe profileprofile neasuredbymeasuredby aa polntpoint gagegage isis shosnasshownas aa sol"idsolid llneline withwith datadata pointspoints asas circles,circles, andand aa profiS"eprofile takentaken atat veqyvery 1o'rlow speedspeed vithwith thethe sonicsonic transducertransducer withwith datadata pointspoints asas trianglestriangles isis sholnrshown asas aa secondsecond 1ine,line. TheThe voltagevoltage outputoutput inin thlsthis casecase wasl'ITaS reasuredmeasured byby aa potenti-ometerpotentiometer becausebecause thethe oscillographoscillograph penpen waswas notnot sufficiently accr:ra,teaccurate toto showshow thethe resolutionresolution capabilitiescapabilities ofof thethe instrument.instrument. TheThe errorerror arisingarising frorofrom thethe motionmotion ofof thethe towingtowing camiagecarriage hashas beenbeen eorrectedcorrected

on thethe basis of estimstedestimated phase skiftsshifts inin thethe recorderorecorder o As nentionedmentioned in thethe precedtngpreceding paragraph, itwitlitwill be noted thatthat thisthis correctj-oncorrection bi"ingsbrings the dlmaniedynamic recording into close confor:nitywithconformity with thethe static record"record. OalyaOnlya fewiew points are shorrnshown sineesince it 1gaswas diffieu].tdifficult to establish thethe instantaneous position of the moving tolringtowing carrlage"carriage. !,tAt the point shotm,shown, canscams on the tracks aetivatedactivated tbethe $arkermarker points,points. ?heThe sonic record and the point-gage difference which arises frorafrom geonetricgeometric error can be resolved by appllcationapplication of Eq. {Z}.(2).

Fi'guresFigures 6 and 7 show a conparlsoncomparison of the samesarne two water waves as recorded by a capacitive eapacitive wave recorder and the sonic-savesonic-wav~ recorder systen.system. ?heThe~teepness steepness shcffinshown in Fig. 7? is lnin excessexeess of the steepness reconunendedrecoffilended for recording sithwith the sonic transducer.transdueero WhenUhen thisthls instrumentinstru*rent is used in the presence of objects objectsotber other than the water surfacesirrface (suchas boat models, towing­ ioring- carriacarriagege support members, channelehannel walls,*ra11s, etc.), the distancedistancefrom from the ranging #' head to the nearest point onoa the objectmnstohjectronrst be greatergreat*t thanifrun the maximumnaxj:nurn dis- d.is- tancetanee --fromfrora the ranging head to the trough of a wave. Havee A flat surfacesi:rface above thethe ranging head,head., a distanced:istanee less thanthan the maximummaxinnm distancedistar:ce from the the ranging f head tots thethe water surface, shouldshorrld alsonlso be avoided. avoidedo Both of these conditions cancan resultresuli inin the instrument'sinstn:rnentrs rangingranging on thethe ' solid solid objectobjeet insteadinstead of on the wave1Eave surface, whenever the wave is1s a greatergreater distance dlstance from frssihe t he ranging head thanthan the the solid sol-id objectobjeet isis fromfror* the the .rangingranging head. When &lhe:r the presence ofof inter­ inter- feringfering objectsobJeets cannot cannot bebe avoided, avoided, aa layer layer ofof glassglass woolrooJ- overover thetbe offendingoffending surfacesurfac€ canean usuallyusually reducereduce itsits effecteffeet toio a a negligible value.?a1ue-

InIn operationsoperations involvinginvolving morer,*ore thantha:r oneone unit,unltr interference interference fromfrom the the directd.irect transmission transrf,lesion ofof the the secondsecond unitunit wouldwou-1d resultresult unlessanless thethe direct-trans­direct-trans- missionmission pathpath werewere greatergreater thanthan thethe total total pathpath ofof the the soundsound fromfrom the the rangingranging headheadte to thethe troughtrough andasrd returnreturn underunder the the conditioncoaditioatlrat that allallun:ite units were were designeddesigned toto "trigger"Rtriggerir thethe sparkspark simultaneously.simultaneously. IV.rv. CIRCUITclacur? DESCRIPTIONpEscRIIltIObI

AnAn overall overall blockbleck diagram d.iagran (Fig.{fig, 8)8) showsshorws thethe sequence sequenee ofof functions funetlons performedperformed byby thethe individualLndividual elementselements described deecribed below.belol+,

A.A, PulserPulser

TheThe Thyratron?lryratron V V,3 (Figs.(Flgs. 8I andand 11)11) providesprov"ides aa pulsepr{se ofof current current for for thethe transmitter transmitter by by discharging d.ischarging aa condenser condensetr throughthrough thethe windingofwindingof thetbe primarypriumr;r , ofof the the spark spark coiLcoil, The The thyratronthyratron isis triggered triggered atat 120120 cycles eycle$.per' per secsec by by thethe power line.1ine.

B.B, Spark Spark Coil Coil andand GapGap

TheI'he discharge discharge ofof thethe spark spark coilcoil energy throughthrough a a short gapgatrl producesprod.uees thethe sound energyenergF for echo ranging. ranging,

ThiThis.s sound energyenergyhas has the nature of a weakseak shockwhose speedspeed. of prop­prop- agationagatlon is very nenearlythat arly that of sound in airairand and has a steep leadingleadj-ng edge whiwhich ch is quite suitable for this application. applieation,

The firstfj-rst half cycle correspondscorcespcnds roughlyronghlyto to a 100-kc100-ke sine wave with a peak pressure on theihe order of J00300 to 500 dynes perper sq cunem at a distanced.istance of 5060 st,cm. ?hisThis a:nplitrrd.eamplitude varies eonside.rablyconsiderably with various gep~ap aridths,widths. The gap lridthwidth eancan be used to adjust tbethe intensity of ihethe transmitted.transmitted pulse when re-re­ qaj.red,quired.

ll Some smallerrorsmall error inmeasure*entin measurement is introduced.byintroduced by ihethe nbuild.-epII build-up ti:netttime of thet he voltagevoltage aerossacross thethe gap before gap breakdorm.breakdown. ?heThe breakdosnbreakdown does not oeeuroccur at thethe samesame tlmetime r*lthwith snccesslvesuccessive dlscharges,butdischarges, but thisthis varlationvariation is saf-suf­ ficientlyficiently snallsmall toto bebe ignored"ignored 6

IiIt hashas beenbeen fow:dfound thatthat emoothsmooth operationofoperationof tbethe sparkspark depend.sdepends onon thethe surfaeesurface ofof thethe electrodes"electrodes. Sar:dingSanding efof tl:ethe eleetrodeelectrode sithwith aa fi.nefine emeryemery elottrcloth willwill restorerestore smoothsmooth perforrmaneeperformance wherrwhen thethe sparkspark hashas beeonebecome eruatic.erratic" ?hisThis ap-ap­ parspears necessarJrnecessary approrS.natelyapproximately afterafter ev€ITevery j+4 frrshrs ofof operation"operation. ?heThe duratj_onduration ofof operationbetlreenoperation between eleaniagscleanings hasbeenhas been fsuadfound tovar5rto vary lrithwith differentdifferent materials.materials. ElectrodeElectrode raateri-almaterial fre:afrom siloil brrnerburner ignitionignition eleetrodeselectrodes hashas beenbeen for:ndfound mostmost sati-sfaciorysatisfactory toto d.ate"date o 6

C. I{icrophoneMicrophone

?heThe receiver is a solid.solid dieleetricdielectric condenser uricrophonemicrophone described in Reference [2]. ItsI ts eonstructionconstruction details are shown lnin Fig,Fig. 9,9. The fll:lrfilm nsedused agas a diapirragndiaphragm. is plated nylarmylar of approxinatelyapproximately 0,00050.0005 ln.in. thickness.thiclmess.

The nrlerophonemicrophone frequency response tsis nearly unlfor:r*uniform to 1 negacyele.megacycle. TbeThe transistor pneanplifierhaspreamplifier has a frequency responseasresponse as shown in Fi-g,Fig. 10. fheThe Iowlow sensltivitysensitivity in the frequency range below 20 kc reducegreduces the i-nterfereneeinterference fronfrom arnblentambient noisenoiseto to aavery very low value because of tbethe high attenuation of t',hethe higbhigh frequencies in air.

D. AnplifierAmplifier and &aplitudeAmplitude Dlscrj^ninatorDiscriminator

The prrlsepulse didiscriminatoris s crirninator ls a one-shot eathode-cathode-coupled coupled nultivibratormultivibrator whose purpose is to dlseri:ninatediscriminate agaS.nstagainst noise by acting only when the signal-signal leveLlevel rises above a certalncertain value. Itft also provides a sharp pulse to temi-termi­ nate the timingtlning proeessasprocess as precisely as possible,possible. AmplifierArnplifier VO3Tr3B,38 (fig.(Fig. 13)f3) 37 1sis a plug-Lnplug-in unit"unit.. ftsIts purpose is to provide sufficient voltage to operate the discriminator.discri:x.inator,

E.E, Phantastron Delay Fe1ay

This?his circuit clreuit provides a 300-1J.300-p secondseeond delaydelayto to permit equilibriumequilibrim tots bebere-established re-establlshed after thettre circuit eireuit is disturbedd:isturbed by the transmitting pulse and to increaseinerease the resolution of the succeeding eucceeding timingti-r*ing circuitry.cireuitry.

Since the accuracy acergaey of measurementrseasurer*ent depends onen the accuracyaceuracy of the entire timing unit,unlt, this delay must be very stable. The phantastron appears satisfactoryinsatisfactolyin this application.applieartion, ThisThj-s unit is manufactured by the Engineer­Engineer- ing Electronic Corporation of Pasadena.

F.F, Bootstrap SweepSveep

The bootstrap sweepsneep circuit,ci:rcuit, Reference [4],[L]n is a negative -feedback­feedbaek- typeiype - sweepsraeep generator that develops a series of voltage pulses of triangulartriangu-lar ttswitch ll shape whosesbose amplitudesaroplit'udes are proportional to the time tine fromfrorn II switch offoffs of thetbe phantastron delayuntil delayuatil the tbe amplitudeanplitade discriminatordiscrirainator is'is* returned to Itrestnrest con­con- ditionllditionsby by the tbe echo. Time duration measurements are converted conYerted inia this thls way to voltage amplitudeanrplitude measurements.nsasurements, 7

G. HoldingSol-ding CircuitsCircutts

Thefhe output of the bootstrap sweepstf€ep is a series of triangulartriangrrlar pulsespu1.seo of varying amplitudearrplitude andand. duration which shich would notnot' be veryve:y suitable for use r:.se byb;r a direct-writingdlreet-sritlng oscillograph.osei3lograph. The holding hotdJ-ng circuitscircuj-ts provideprovlde a preliminary filtering. The first circuiteireul-t chargeseharges a condenser C 0r, to the peak ofcf the boot~ boot- filtering.* 23 strap output.. o*tput" Thisfhls charge is heldheLd until the start starb of the nextnex! pulse when it is discharged by V Y*22 to the value of the bootstrap voltagevoLtage at that instantinstant" .. This?his results in a series of voltage voltap steps which whieh correspond correspond,to .to wave heights height's andard. a superimposed negative triangular trianguS-ar voltage. The second eecond holding holdlng circuit charges a condenser condens"" CClrg to the value ve1ne of the condenser voltage C C, of the firstfl-rst 49 23 u holdinghoLding circuit during itsite ltholdshold periodperiod,tro The resultantresrrltant output voltage is a seriesserles of steps which whieh approximateapproxlmate the formfor*r of the water wave..wav6o The lowlolr pass filter actionactionof of the succeeding recorders smoothsnooth this output into a E continuouscontinuoue line..Llne" This?his whole vholeprocess process of samplingsanpling and snd detection detectioneould could be interpretedlnteryreted anal­anal-- ogouslyogousl]r to techniques iechniques of sampling and detectiondsteciion in a pulse-timeprlse-tirae modulationnodrrl-at,ion system.systemo

vvo0 ACKNOWLEDGMENTSAcK$0i{ffirc3{gNT$

Thisfhis instrument lnstruraent wassas developed and and. constructconstnrcted..ed by the St St. 0 Anthony Falls Hydraulic l{ydraulie Laboratory for the David Taylortaylar ModelModeL ~sin$sin under contract SobsNobs 72117,7211-7e Task Order0rder 1110 III.

Thefhe developmental developnental- program was uvrderunder the general directiondireetlon of DrDro ..

Lorenz G..Straub,So Straub, DirectorCIl:ector of the StSt. 0 AnthonyAnthory Falls Hydraulicffirer:Iic Laboratory.Laborateryo The developmentaldevelog:mental- progra$program wassas supervisedsupe:srised by JohnJolm MoSo Killen;Kl13-en; FrankFrarjk Schiebe,$chiebeu GoffeGof,fe Erickson,Eriekson, andard Norman3{or:ngn Viss did the experimentalexperinental testing, developing, and constructing. esnst:nrcting" In addition, their numerous numerolr.s suggestions and clarificationselari-fications deservedeserye special acknowledgment. acknouledgnent "

Thefhe editorial preparation was€as underrinder the generalgeneraL directiondiroction of Loyal3,oya1- Johnson, the manuscript waslras prepared bybf Delores Grupp,Srtrpp, and the drawings were prepared by Frank I'rar:k Tsai. Tsai* 8

],LISIST T OFa F REFENESCESREF ERE N C E S

D. Van $ostrandr L953, [1] Black,B1~~k, II.H. $.S. Flo$rl3&ionModulation 33gg.Theory. SewNew Yorlr Yo~k: D. Van Nostrand, 1953. n0ondeneer tI l2l(2) Kuhl,'W,Kuhl, W. "Condenser fransmlttereTransmitters and Hicrophorrcs.lrMicrophones. $eustiearAcustica, Yo1.Vol. hr4, .pp,5t3-539.pp. 513-539. 1954.r95b.

[3]t:] NatlonaLBureauNationalBureau of $t,andards.Standards. HandbookIlandboek Pref,erredPreferred Circuits.Gireqits. Washington,I{ashiagtoat D. C.: Superintendent of Document~, u. s. Government Printing .Office,0ffice, 1955.L955.

[4]tl+] MITEI? Radar Hadar School$chosl Staff. Principleser*:teiplp: of Radar. Bi+ar, SenNew York:Iork: McGraw-Hill,ScGrar-IlALLt 1944.19id+. .. '.

-----..,..-TTgJ}g!FIGURES (1 throughthroush 15)

• 1111

'.

Fig. I1 - - PhotogrophPhotograph of FrontFront PonelPanel 1212

t: ti

Fig.Fig.2 2 -- PhotographPhotogroph ofof RangingRonging HeadHecd ) f-I 13W

_\ @ ro38

\

ro I 1035

'r'FE$ • .Ein b Moving S3carriage EE

E,*._)

bgerror rH oo o Lrecorder o 30

Record ggg ro SSEgage €s- ,"'at. feet/sec 1 reading paper ;Pi-EEEfiEHEstimate 10feetlsec Sonic Jog Point 20feet/sec 00 8E89''9 5 R -.]ftl 6. lIE 'V ¢ 0 0 *

Otr<>x++ ---, -L 25

_/ + ft ry * O s 40

il = A

F ||,,Eft, 2 e.tlfeet oll= 20 in N.= rH o 9y

.E*Wave --

- o - -- i53Distance - I c -- o9 - , co

roog15 N Mechanical \

ig'Horizonta IO J Large I

(Y' 3 - ; \ ii Fig. \= NrJr{ 9 10 \ \ \'^ -\

\ *^ 5

\

\

o o 5 0 0 2 8 6 . . . . . a q . 1 1.4 1.2 1.8 1.6 AI I !9 o 2 2 0.4 0 0 o 0 ::I E Q) Q) Q) Q. =

+0- ul +0- "0 epnlldr.rry« lael - I-' th ~

\ I -+--1 II 3.00 I

-- |r) 75 . ~)- \

$l 2 I /

'isP$ ':€ csin 50

"\ . 2 Moving carriage ) error E,=',;E recorder Record

gage T ro

A{ 25 feet/sec . reading poper g;g-glEstimate (\l ;rt 2 15 Jog Sonic Calibrate 7.5feet/sec (L(/r()?I{-Point -'lI I o D. o -*- \l <> o otr<>oo f -r o

o+ft (\i c.r2 2.00 I -_+__ .< A=

- + (l, "',\ -

.og .=in., feet ^-Y I \c!

1.75 grl in --+- 1p-(, H = 2 c. c) A\:: o- -- !

8.E =Wave --+- -o1.50 Distance E Q.l o - o'--

- 2o ,*2 E _.c: -/ Oo - Mechanical , 1.25 -+1 e-: *

.. o -LO Horizontal 0011< e tt Small I

o{4 - q . 1.00 o) t; I Fig t |o

\ 75

\ .

o0 \ ;-Y 50 . 0 \

lO I' , (\t 25 .

o0 I I l/ I I ' o

o (o sf 0' 12 20 08

(\I . . s8 . o04 . 0.16 0 0

0 o o oci o0 Q) Q. :s E J:: Q) Q; .... -a

Fig.Fig. 55 - - PhoiogrophsPhotographs of of TowingTowi ng CorriogeCarriage ondand MechonicolMechanical WovesWaves 0'- 16I-'

-o o o o e. Record, 0, o

= Wave () o vt Sonic 't with T o o

c..) Record o U> 'd '-o ;> .i Wave Sonic o, )u.) U Capacitive =ro ._-o

&o0.055 oll (J-=

Capacitive q =c)vc of eA- ^ (1, ;c,(/) = Steepness

Ee

oe ft,

UcoComparison r\O.o. 'o 6 -

ci0.693

t',,l = u! H Fig. 17T7

,

H-ttt : I!

: ITll i! .1: . R:1 . rr .~

..

CI.>() > ..;::+ ·u(, co c.. co lum uU

.. i Ii n

B

filE m Q) rBI-' Output -

>to

--85CR3 C= E,ESupply

eboand 3e *FuFloating !e Eg Volts Power Volts

o CR2 435

gn 210 Unregulated F;Regulated t-­

+ l')

t-- o I

'= 23 $l .=R o

V26 f 5>V 3> '1* o.! 9al

32 c Circuit to ai Circuit o t LN V E'fr 34 F i'a!g Transducer First V22, V25,

E.gt V o Second -'> Regulator E Power e .g' t 31, =-.

> V o 21, a t; o (\l c tb L Holding 33,

Holding G

->V E$ V24, I

t:;3 V

Main o 30, o =)V

6 Supply

= Wave-Profile

r---t (, c o L V, Sonic @ r9o o of VI8 o; !r oto 36 E :.=>V o E L rPsn 17, o o a, -N ED V V20 3'; 'o .9

Sweep E olf)

o Diagram • A'-' Amplitude

EBootstrap <.9> (D(c) V35, J

o Discriminator o > V16, o ao Block E c o & f-- I-

Power () Supply l IL Functional c 3o I taE L@ o o, l!) @ CL 8 - V38 Sync I-- ;E-?o 6z-Supply E E' V9

and ii Fig. Delay i:First E> ,og Es o 37, E o.= Amplifier I bn Line I

&9V Q3 Phantastron (L dlBias 5 =o =ss o a) Q2, EEand o .9 c-- lector roo- QI, Microphone Preamplifer

= do I Ref

>u}o}r--t"b/ Sf ~f V , f

.-/\ f \ \ \ \ Gap V3 "7//////7///////&// Pulser a Spark Coil )

10 I-' 'D

=-lo

-cteE -c :+ P=$ 'rt > LC) 9E gst/':-

o

T Housing

1t c) f c -o- o

1 o plated

P Preamplifier lID f oF -o parts m_ o-= = 9l -'E o and thread

nt =~I~

Threads/inch o -r t

()chromium fine • o I o 10 Tight'~d .1

= Microphone I spec 7/8"cj>-28 o. 9 - . ~

rL Fig 2L:t, I I 8 6 1.1 B€ o ;_-o 69 (,c) (,O riFA gE ci} ~§§~;~;§~~;; -ots o-b lr) acuorDalc020' Itl Alo o t-c "~ 20

106 1000 r__------~r__------._------___,

10/n5VE5 ?en 100 -E CDo .c.s 'tl!t ~J o0 ;:.= - Q.o. CDo (Jo E c:c, o0 « 'tl!, CDo CDC' c..CL > E 0o -Q)o ~ 4 E,0::: 10 -c.. 10 ,otE c:

______~103 I ~ ______~ __------_--~-- t03 1000 I 10 100 to@ FrequencyFrequencY (Ki(KilocYcles) locycles)

Fig. l010 - Frequency Response of PreamplifierPreomplifier ) f"\) 2tI-' I I I I I I , .J ___ Gap I r--' Spark I A 4

d.sP o-Pin

@ Y

o n = gd11 IS C R46

s E, f;1 J---o® 7 ~nc F C o1 () C RII B+++ -----41 \S4 Y 6-t

ll+, oo

L F@- c, t, -4ftr+ o Pulser @® E o- I - 11 tt,

a, T2 Fig. . c t! E a, TI

o • E .> V o o c, ro o IL Filament d 1>6.3 t: Transformers I V3 , ~ • --4.t___-- )\OS., ......

E c crl SI |!- () F> I o J,- b-9 .=\(, (, ) olE El>r pifi -c(|, A o- Vac Cycle o-t"\ Delay Unit J!.,.. FOThermal 5@l>c) ---D 1 3 too P ff; R 115 Pi~ 60 Pin :(o df N 2?N B+ 59 C

o +o E L o

o Discriminator C' ! f + 106

R E Amplitude at

oand c

+

+o

• o

CL Phantastron I I I I I I I I I I I I I I I I I I I 1 -----''t x ....I o R41 T __ R38 a Delay

I - ,®. 6l 12 o,

IJ. Fig. ) ------1 ~------I I I I I I I I ,------) f\) 23w

o

oRA Cl (I)

o- B-200V I I I I I I I I 1 I I I 81 ~ I 51 P31Pin C .... (' __ L...- ______~ B++

o ifiers RS6 C\l ()lo tr Ampl

Itb (Js€ I - I t- (') 13

o)

t! Fig.

g l\(ts F o

g 3E ______(J L r------N eb.c::- A B |r) c oc

(L P5 P 5 P E,Pin o- iI

f n'+Elpin R53

tT 6Output

roN E o F ttt (\l (E () c |.'vl o sa E IE o s N u-Filament e c) +(E fr31 V @ N o

+8, F To AA

|., ULI o E L TI

UCircuits o o) ,al o "tr N ;r E. o @ ! N o E lisl I Holding !

co 1fR2?;jIII~ Alc' oand o- TE it 0, IN c, N 3

tll Sweep

• o

N + t- I o E E 3 Bootstrap

.d I - s,"N *

I 14 E, .d[; o)

u- Fig. ! Is '6o .qs; df.u h.rs 1J*f d[' (, N CE B+

l4AA4

.i J lo

r------B+++

~ ~

1----_-...... PP3 3 Pin A t*" f P3 r PinC J'

~------~----~----~~----~----~--1---~B+

Ra5

Raa

®

Fig.Fig. 1515 -- PowerPower SuppliesSuppl ies 2727

PARPABrS T S LIStrsf T E--F-

Referencefieferenee symbolqrrnbo.L code:eode:

(a){") Fig.Fig. 11IL pulserpu1ser (b)(b) Fig.Fig. 1212 delaydelay phantastronphantasbron andand amplitudeanrpS.itude discriminatordlscrinj-nator (c)(c) Fig.Flg. 1313 amplifiersanrplifiers (d)(d) Fig.Fig. 14il+ bootstrapbootstrap sweep$reep andarrl holdinghol_ding circuitscircuits (e)(e) Fig.Fig. 1515 powerpolder suppliessupplies

V3w (Vl)(vl.) 60126atz (a)(a)

V9vg 6AS66As6 (c)(c)-- (.11

VlOrIO (V2l)(Ver; 6AL56A15 (c)(*) , Vl61116 (Vl8)(\rls) l2AV712AW (d)(d) Vl71a7 (V20)(Veo; 6AL56AJ.s (d)(d) Vl8r18 (Vl6)(vr61 12AV71zAW (d)(a) V20v2o (Vl7)(rr7) 6AL56AT5 (d)(a) V21vz]. (VlO)(V:O) 6AL56rJ,5 (d) V22v22 (V26)(vze1. ~ 12AU7 (d) V23v23 (V?9)8?9) . 12AU7124U7 (d) vzb v24 (v25)$zg 12AU712An7 (d){d) v25 ((w)-}l29) --- . 12AU712Ag? (d) v26 ((v22)Y22) -. . 12AU772AV7 (d)

Y2BV28 oc3OC3 (d) v29V29 ("uzsj-(Y4-3) , . 12AV?12AV7 - (d) . v30V30 5v45v14 (e) v31V31 64A56AQ5 (e) v32V32 {v33)(V33) L2ax712AX7 (e) v33V33 (vtz)(V32) uArr12AX7 (e) V3l+v34 >o>L5651 (e) v35 {ne)(V36) 1zA\j?12AV7 - (b)(b) w6V36 (w5)(V35) a2AV?12AV7 (b)(b) v37 6gB V37 Ge)(38) 6u8 tubetube {c)(c) v3BV38 (3?)(37) 6uB6u8 tube tube (c)(c) alQl 2r{2h72N247 (ncl;(RCA) (b)(b) Q2Q2 2N2w2N247 tncl;(RCA) (b)(b) a3Q3 2w2w2N247 {ncel(RCA) (b)(b) c5C5 l+?47 p,$I-L¢' hoo400 v V (a)(a) c6c6 .5.5 Ff,t.d' 1OO01000 VV Bathtr$Bathtub CapacitorCapacitor (a)(a) cTC7 25o250 su& J.l.t.d' hOO400 Y V (a)(a) CBC8 1.01.0 Fft.d' 5ov50 V (')(a) 09C9 10o100 Hlfllt.d' l+m400 V V (a)(d) cLoC10 .1.1 l'f,pf Loo400 v V Attenr:atorAttenuator (A)(d) cltCll 3.31-CI1310 p,pf,I-Lt.d' AdjAdjustable ustable !4ica*lrtwrerMica-Trimmer CmbinationCombination XIn PqsitionPosition (d)(d) 612012 262a2620 stllt.d' It.. tlIt t 11 il11 p.X2 oIt (d)(d) c13C13 391+03940 ppffJ.t.d' tr.. EIt &It trIt x3X3 uIt (d)(d) 2B28

clhc14 52805280 F{l,f~ AdJustabl-eAdjustable F1iea-Tri$nerMica-Trimmer Colttbi-nationCombination Xl+14 AttenuatorAttenuator (d)(d) c15C15 7900 pp^fp,!.ti' $n||sIt It It 1I x6X6 PositionPosition (a)(d) c16C16 1o55o10550 $pf,p,!.ti' trll|t{It It It It X8X8 llIt (o)(d) Cl?C17 1310013100 ppf,p,!.ti' $BnRIt tt It It EOno $" (d)(d)

C18C18 .1.1 pf,!.ti' l*0O400 Vv (e)(a) c19C19 2020 pf,p.f l#o450 VV HleetElect (a)(d)

C23 .0025.0025!.ti' Ff hoo400 vV (d)(d) czbC24 .005.005 pfp.f l+oO400 Vv (d)(d) c25 "oo5.005 Ff,p.f hoa400 vV (d)(d) C26 2020 Ff,p.f li5A450 VV El-ectElect (d)(d) C27 20 1tfp.f l+50450 vV E1ect,Elect (d)(d) C,28C28 ""o5,, 005 Ff,!.ti' l+OO400 V {d}(d) c3oC30 "101 F.f'p.f boo400 vV {d)(d) c3lC31 .ml+0004 Ffp.f l+00400 V l*caMica (e)(c) C36a35 Lfo470 pn:gp,p.f (t)(b) C37937 .Ol001 u,fp,f (b) C3BC38 .0020002 Fl:pi' Lgo400 V {b)(b) C39 ,0020002!.ti' Ff l+0O400 V (b) Cl+OC40 390 pldp,lli i+OO400 V (a)(b) cl$CLl "1.1 ufUf 50 YV Seramic,Ceramic, $pragueSprague sriniaturizedminiaturized type HLOFlO (u)(b) Ci+2C42 40 I+O Ffpi' l$o450 vV sl-eetElect (e) .C43c!3 40 l+o Ffp.f 450h5c vV Elect&lect (*)(e) C44clrl 20 pJpi 450lr5o Vv Elect (e) C45cl+5 1 lJ.ft.rf 6oo600 vV te)(e) c46cl+6 01"1 trfpi' 6005oo Vv (e) (e) . C47oW 4700htoo ppf,p,!.ti' 400l$o Vv '(")(e) C48 20p.f20 pf, 450 Vv ElectEleet ' (e) cLB h5o ' * C49Cl+9 ~001.001 pi.'Ff, 400l+0OV V (d) C51ClL .1"1 p,f$f 50 V Ceramic,Ceram-ien Sprague $prague' miniaturized niniatu"rized type P10 HLO (b) C52e52 .1lliD"1 $f,D 400l+OO V (b)(u) c53653 47 l+7 ll!ll$if 400l+Oo Vv (b)(u) .055455 68068o \l!.ti'prlf, 400l+00 V (b)(u) A-C56:: 56 .1 p.fFf 400l+O0 V (b)tu) C57c57 47L? ~F4f 400hOO V CeramicCeraxric Capacitor (b)(b) C59859 .03.o3 jifD1r.fD 400liO0 V Paper Capacitoreapacitor (b)(r) c60C6O .05.05 IJ,fDilf,D 200 V Paper Pa5:er CapacitorCapacitor (c)(c) c61c61 001.01 piDpf,D 6006Og V CeramicCeramic CapacitorCapa*itor (c)(*) C62c62 50050o p.fDprP 6006OO V CeramicCerasdc CapacitorCapacitor (c)(e) c63s63 150015so p.p,fD$dB 600600 VV CeramicCeramlg CapacitorCapaeitor .((e) c) R8R8 100100 KK t* wattwatt 20zofr% (a)(*) RlOm0 11 ohm chrn 22 watt watt 20zo'fi% (a)(a) Rl1Rn 1010K K 2525 watt walL wirewoundrrireworznd (a)(*) a Rll.!.Rlir 1I megmeg t? wattwarr 2020fi% (d)(o) Rl5ru5 820B2O KK, ,. 2"t wattI'ratt 202sfr% (d)(d) Rl6ar.6 1I megneg potentiometer, potentiometer, finefine rangera+ge 20%2a6 (d)(o) Rl7&r7 1010r K 11 wattwatt 20%20fi (d)(a) RlBHr8 100100 KK t3 wattwatt 20%20i6 (d)(d) Rl9Hrg 1001CI0 KK 1I wattwatt 20%2076 (d)(d) R20820 220220 K K 11 wattsatt 20%?AF (d)(a) R21R21 66x K 1l- wattwatt 20%2A76 (d)(a) 29?9

R22ts22 2525x K 1010 wattwatt wirewoundvireworud (d)(d) R24H2I+ 3939K K 1 wattwatt 202afi% (c)(*) R25M5 1010K K f"1 wattrratt 202Afr% (d)(d) R26p26 3939K K f wattwatt 202afi% (d)(d) .R2BR27s27 150150 Kr ywattwatt 2020rt% (d)(d) R28 1.81.8 meg f watt 2020fi% (d)(d) R30e30 2.22.2 megmeg f wattwatt 20%20fr (d)(a) R32n32 2.22.2 megmeg f wattwatt 20%20fi (d)(a) /ol R33833 1010K K f watt 5>p% (c)(e) ,,q R34R3l+ 180180 KK zE wattsatt 52ra% (c)(c) ,.q R35R35 3333K K 11 watt 5,/e.% (c)(c) /d R36il6 2.22.2 KK 1I watt 5,p% (c)(c) td R3783? 4.7l+.7 Ktr 1.2$ watt 5%,p (c)(c) rJd R38 2222K K 11 watt 5>lo% (c)(") ?-R.-w939 3333r K 1I watt 5,h% -{s~+€)-* ... R40nl+O 330 K t$ watt 20%20'6 (c)(e) Rl.w.Bt'I 1I meg potentiometerpotentiorneter ~*S* R45J[4) 2500250O ohmsoiras 1010 watt wirewound ulrewound (d)(d) R46nh6 27 ohms 11 watt 20%zofi (a) R51 100 K twatt$ watt 20% (d){a) R52n52 47I+7 Kr 1 watt 20zafr% (e) R53e53 505O Kf 2Q wattnatt wirewound pot (d) 7.45hR5-4 - 33 K |wattwatt 5$fr% w-+b)* =R-e5*5-5-- 33 KK. zwatttfwatt 5Sfr% -(~*(b)*- R56e56 3939K K 1lwatt watt 20Z:O'fi% (b)(u) --,.*6+-. --:;-RG; 4704?0 K t$watt watt 55%% ~-++**(~7~'- '-r#T-t862- 680 ohmsoturs fwattf watt 55g% *{#F-~b:t· ~ 100 K zwatt*watt 5F5% *4&n-- ~ ~=-86h=. 470l+lor K 1. watt .4b)--~ *.#* $wattf #~ --R65- 68068o ohmsonms zwatttsatt 55g% ~*{&+ R71 1001OO K potentiometer, sensitivityseqs_!!ivi_!y contre4control (b) R72n72 100loox K t;watt- watt 20%Zofi (d)(a) w3R73 10108 K 101B watt wirewoundwirevor:nd (e) RTlrR74 20K20 K 101O sattwatt wi:ewoundwirewound (e) w5R75 l+f47 rK 1 watt 2620% (e) n76R76 h?o470 rK l-1 watt 2&20% (e) w7R77 4/U470 OnmSohms *wattt watt zafi20% (e) R78 27027A K 1I watt 2020fi% (e) e79R79 22K22 K 1 watt 2&20% (e) J{,OUR80 h7x47 K 1,1 walf watt zafr20% (*)(e) 1 aBlR81 l+747 anmsohms ?ywatt r{art ?$fi20% (")(e) BB2R82 l+t47 rK 5z sattwatt 2&2al (*)(e) a83RS3 100 K 1 l"attwatt 2&20% (e) RBI+R84 Lrr47 K 1 watt zofr20% (")(e) -1 . BB5R85 l+"?4.7 meg 2p'watt watt 2&2~ {e)(e) RB6R86 5or50 K 2 watt trirewoundwirewound (*)(e) R87 10r10 K 2 sattwatt wlrewoundwirewound potenti-oneterpotentiometer (e) r BBBRSS 30K30 K 2 uattwatt siresoundwirewound (*)(e) RB9R89 l+t47 rK ]~ watt zafi20% \qi(d) R90R90 h.74.7 meg pfwatt watt 262at (b) R91R9l 68S680 K pY rrattwatt zffi20% (n)(b) R92 150 K ff rrattwatt 20fr20% (b) s93R93 27827 K F2 sattwatt z}i[20% (b)(b) 30

R94R9h 6805BO K t watt 20%20fi (b)(u) R95n95 2222K K f watt$att 20%2afi (b) R96n95 2222K K f wattsatt 20%20fi (b)(r) R97e97 470l+70 KIt f watt 20%20'6 (b) R98898 1010K K f wattlratt 202a%% (b) R99n99 100lmK K ! watt 20?afl% (b) RlOO&100 470h?o ohmsotnas ;0 watt 20%ZAy" (b) 47l+Z Kr ~I watt 20%ZAf" (e) Li3&01J UOl 1 Rl02a102 470l+fo Kx "2t watt1tratt 20%2a% (d)(a) Rl03R103 100 KE ohms ~1 watt carbon resistor (a)(.) Rl04HLOL 10 K ohms ohros 1 watt$att !20!zaf,% carbon resistor(b) Rl05a105 101O KS ohmsohns 1 watt :20lzafi% carbon resistor(b) Rl06RLO6 100 K ohmsolms ,I watt !20!zof,% carbon resistor(b) tI loary Rl07m0? 4.7Ll.? megohmraegchn "2 watt?ratt !20- LV/P% carbon resistor(b) * r'ot Rl08trroB 18001Bc0 ohmsonrus 1 wattI{att !- 5>/o% carbon resistor(b) Rl09Erog 270 K ohmsclurs 11_ watt carbon resistor (c) :rf RllORLl0 101O K ohms otur:s "22 wattTfatt carbon resistor (c) RlllRrll 22 K ohms 1t_ watt carbon resistor (c) Rl12 2700 ~wattI watt carbon resistor (") RTL2 2700 ohmschms t (c) Rl13Rr13 330 K ohmsohns watt carbon resistorrnesistor (c)(") Rl14enL 270 K ohmsohrns i"2? wattItratt carbon resistor (c)(") Rl15Hr15 47h7 K ohmsorrms 1 watt carbonearbon resistor (c) 1 (") Rl16fir}6 ·470h?o ohmsorrms t4 watt$ratt carbon resistorresi"stor (c) Rl17RTLT 1 megohmnegohm "2:{ watt carbon resistor reslstor (c)

The followingfoLlowing componentsconponents a:re aI€ contained in plug-inplug-ln units manufac­raanrfae- tured bryby EngineeringSngineering ElectronicsSlectronics Corporation, Pasadena,Fasad.ena, CalifCalif6rnia:brnia:

1st phantastron delay, Z877l:7877Lr

R33,Rl3, R34, B3l+, R35,fr35, R36,&36, R37, R38,R3B, V9

Tl Power transformer;transforxrer; primarypr3xary 117 volts 606O cycleseycles AC; secondaries: secondari.es: 250 V.C.T.v.G.?. at 25 ma, 6.35o3 volts at 11- ampere;ar*perel Stancorstancor PS8416PSBL16 (d)

T2 PowerParrer transformer;transforrner; primarypr5:aary 117 volts 605O cyclescycLes AC; secondaries: 750?50 V.C~T.V.C.T. at 150 ma,w, 5 voltsvolt,s at 3 amperes,arrperes, 6.3 V.C.T.voc.T. ataL 4.5l+,5 amperes;amper€si Stancor$taneor ?SBI"*1PC8411 (e)

?3T3 Filter choke,ehoke, 16 hy,try, 505O ma;mai Stancor C1003C10O3 (d)

T4Tl, Filter choke, chake, 7? hy,b, 150 ma;na; Stancor C17l0C1710 (e)(*)

T5L) FilamentFilaroent transformer;transforrner; primary 117IL| volts 606O cycles AC; secondaryseeondary 65 volts C.T. at 3 amperes;anperes; MeritHerit P-2946P-29h6 (a)

T7 Automotive3n:.tomotlve ignitionigni-tion coil, MalloryHal}.ery Voltmaster Yoltnaster (a) 3131

T8TB Pulse Pulse transformer; transfonaer; Stancor $tanccr A3332&3332 (e)(e)

SlS1 SPST $P$T powerporier switch,gd!.g.!, Cutler-HammerCutler-i{anuaer 8280-K168280-Ff6 (e)(e)

82$2 6050 secondseeond timetjme delaydelay relay, re1ay, AmperiteArnperiie 6N060 6!EO5O (e){e)

83$3 2-pole 2jo1e 7-position?-position coarsecoarse rangerange switch; strlteh; shaftshaft andand indexindex assemblyassenbly CentralabCentralab typetype 300;30O; 22 switch slrltch sectionssections Centralabcentralab typetype PA-l PA-1 (d)(d)

S4Sl+ Operate-standby Operate-standby switch,*ritch, SPST,SPST, Cutler-HammerCutler-Hanrner 82Bo-K16828O-l{16 (a)(a)

PI?1 PowerPower connector;connector; socket AN-3l02A-16S-5p;AN-31024-L6$-5P; plug p].ug AN-3l06A-16S-5sAI{-31064-16S-5S

P2PZ ~3ut connector;eonneetarl socket AN-3l02A-14S-2S;AN-3102A-fLS-2S; plug AN-3l06A-14S-2PA$-3106A-11+S-2P

P3 Preamplifier?Tearnpllfier connector;eowrector; socketsoeket AN-3l02A-14S7s;AJ{-3102A-11+S?s; plug AN-3l06A-14S-7PAS-3106A-1LS-?P

p4Pl+ Spark$park coil connector; socket AN-3l02A-14S-9S;A$-3102A-1lrS-9$; plugpLug AN3l06A-14S-9PAN3106A-1LS-gF

p5P5 Outputoutput connector; connect,or; socket AN-3l02A-12S-3S;Ai\i-3102A-l2s-ls; prugplug AN-3l06A-12S-3PAN-3106A-12s-3p

F1Et 3 ampere 25025A voltvo]-.l" fuse and Buss type HKPIIKP fusefusehol-der holder

DSI Pilot 1anplamp assenbly,assembly, Dialco type 931 series 95220B,gSZZOB, withrrith $E-51NE-5l neon lanplamp •

gfitORl Sarkes-Tarzi-anSarkes-Tarzian H50OM500 silicon rectifier and.and mounting e]-ipclip CRZn$,,ttnrrtrnCR2 " tI II \I It II It tI Cnjn$$H$tlltttCR3 " It 11 " II " " " Cel+Btt$ttn$rilCR4 II II It II tt It " tI cRSFnn'lua$ilCR5 It It It " tI " It tI cR?CR7 lsjLrAIN34A (e)(c)

:,_ 77 0cta1Octal tube sockets, AmphenolAmphenol typetype T?Mtp877MlPB ~'' .6,6 7 pin n:-iniatureminiature tubetube socketssockets withwith shieLds,shields, amphenolAmphenol Il+z-glj147-913 1 71- pi:*pin -nj.niatureminiajJJ,I:§.. tubetube socket,socket, ArephenelAmpne-nel- type-t-ype- 1L?-5OO--lh1-$OO- -E.8 9 pin miniatureminiature tubetube socketssockets withwith shi-eld,shield, AmphenolAmphenol tnpetype 59-l+O?59-407

33 hrobs,knobs, JohnsonJohnson eatalogcatalog rlocno. l=3.6-261-116-261

- j'. ta li.-' "' t -- . , 11 chassis,chassis, aluminum,aluminum, 22 in.in. xx l-?17 in.in. xx 1313 in.,in., trC*!CA -typetype 29023 Z\OZ3 11 pairpair chissischassis r*ouniingmounting braekets.,brackets, 6-t/z6-1/2 in.in. ix 1010 in.lin., BudBud HBI+hBMB448 11 pane1,panel, 1919 in.in. xx B-3/L8-3/4 in.in. xx t/B1/8 in.,in., BudBud PA-IL0'-HAPA-ll05-HG 11 cabinet,cabinet, steel,steel, 1919 in.in. xx B-3fi+8-3/4 in.in. lanelpanel space,space, S'dBud 0Rt551CRl55l ERRATAENNATA

The following corrections in Technical Paper No. 23-B2J-B should be noted:

Page 2 The first two linesllnes of explanatory materialrnateriel following Eq. (1) should read: r -E measuredmea*sured distance CH/2(n/e minusninus wave amplitudeanplitude plusp\us 5-1/25-I/2 in.)in. ) H ..- wave hehelght ight

Page 17U The lower graph should be labeled IISonic."rrsonic.rt The title for thisthls figure should read: Fig.Fig.7-Conparisonof 7 - Comparison of CapacitiveCapacitlve Wave Record with Sonic Wave Record, H = 1 ft, ftr Steepness w- 0.1250,l:25

Page 27 ChangeChang V9 6AS66es5 (c) to V9v9 6AS66456 (b) VIOvl0 (V21)(var) 6AL56^L5 (c) VIOvlo (V21)(ver) 6AL56en5 (b) V16v16 (V18)(v18) 12AV712Av? (d) v16 (V18)(vl8) 12AU7t2AtJ? (d) v18v1g (v16) 12AV7t?Av? (d) V18v1B (V16)(vr6; 12AU7r2hv7 (d)(a) v25 (V29)(v29) 12AU7tzhv? ((a) d) v25vz' (v24)(velr) 12AU7]'2Av7 (d) V29v29 (V23)(v23) 12AV712AVT (d)(a) V29vzg (V23)(v23) 12AU7]:zArr7 (d) V35v35 (V36)(v36) 12AV7LaAvT (b) v35 (V36)(v36) 12AU7rzatJ7 (b) V36v36 (V35)(v35) 12AV7laAvl (b) V36v36 (v35) 12AU7rzAtJT (b) Page 28 Delete .. c55c55 68068o Illlfppr 400hoo Vv (b) c56c55 .1 llfuf 400l+OO V (b)

Page 29 Delete R39 3333K K 1 watt (c) ]1 5% R54t\r4n/l 3333K K f watt 5%5/" (b) R55P(( 3333K K !f, watt 5%51A (b) R61 470hzo Kt< f watt 5%51', (b) R64R5h 470l+fO Kr f watt 5% (b) R65n65 680 ohITSohre 2"f watt 5%5iA (b)(b )