oDIGITAL COMPUTER - LVSLETTER OFICE OF Vol Dl No MATHEMATICAL SCIEMCE VAL RESEARCH DIVISION 4 10I l4l llI TAIII I hl 1411 1 Itt' I l t' ljd J I t l ojo 1 jr 11i%11 4 Whirl OF' t NrKNr I - 1 ro 1itil ai v Comilve HAVD AIC -1I Aliordr ot Vrovit11i i V ou mtlr ' 11 w lhe Oh l VAC The bhOVAt' I h o rialtv % It chigga t ler o li MIDAt N 'heoSWAC 9I Tho Oak Htdge A 1atic C ui luter OKA I b 10 The Inaittul for AIvaned Stuiy C oinpute lAS 1I Computor Romes rch Ct rporationa Compuetelrs CRC Ioth-A CKC I0s CRC 107 Iz I j 4 IS 16 I I8 19 20 ImM Typlw 701 Electronic Dta Processing Machine ItiM Type 6S0 Magnetic Drum tC41eulAtor The Sh AC Contiolldnted Model 30-201 C-osnputrr lPurrough0o LAboratory and Wayne University Cumputers The JAINCOMP-D Aeroncautlcal Rese arclh Laboratory Comnputer OARAC Th ALWAC The MONROBOT MU DATA PROCESSING AND CONVERSION EQUIPMENT I Kearfott SADAC Se rvo-Anu log- Digita I-Anlog-Comve rte r 2 0FV CCP 701 Digital Point Plotter 3 Solid Acoustic l rlay Line Memory Unit 4 MacDonald Magnetic Storage Drums 5 Potter Magnetic Tape Handler S - LIST OF COMPUrING SERVICES I 2 Wayne University Computation Lab Machine Computati Computer Research Corp 102-A Operation Maintenan NOT IC ES 1 Newsletter to be Reprinted in Journal of ACM 2 Joint Computer Conference 3 Joint Computer Conference Publications Available Approved by The Under Secretary of The Navy 27 August 1951 L s - 1 V1 16 11 1t f I OCT 1 ourse LUTl ILLu ' IituwtQnt 1V 1 U C n orAf lo its DISCLAIMER N THIS DOCUMENT iS BEST QUALITY AVAILABLE TIT COPY FURNISHED TO DTIC CONTAINED A SIGNifICANT NUMBER OF AGt vHICH- DO REPRODUCED FROM BEST AVAILABLE COPY NOT THIS DoCUMENT CONTAINED BLA1K PAGES THAT HAVE BEEN DELETED COMPUTERS THN HtAND itIN1til Jt BNNIAC A I II Altil J ohtt jis'g j iheia goas' illso h1s1M ti' gi sI'iilioltod akild IN IIiliowraltl atI lit HIAND and o'lost rital iv Iliko w large i ntowhino aitil s111atl lt %g Thsin 11suis ' I ' I niswhsns' %imp ns il lowi lw I l is'h go0lA t '' i Whssgs ih l ii 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tif October and that the complete guuachigus will 1w operative by 1964 Itt THE I I AC The Illine halt bseen in general use by the Universitty of Illinoi s ince September 1 1953 It wans shut down onl August 1t 1953 to allow the installation of a new met o coverm and some control changes which will inucre ase the addition speed of the machine The machine has been used by fifteen different departments within the Universtty for many different types of research work A library of about one hundred routinet IIAs greatly extended tie usefulnests of the machine to all of these groups PROJEKCT HURRICANE COMPUTER R AYDAC The RAYDAC Computer is now installed and ii operation at the Naval Air Missile Test Center Point Mugu California The machine completed its engineering acceptance tests early in July and has been operated by the NAmiSTnSTCEN staff since that time It is expected that a contractor will take over the computer in early autumn under ant operation and evaluation programn WHIR LWIN Sincp ui I the following problems have been initiated by the Scientific and Engineering Ci6i0Yi btf6i SAEC Group for solution on the Whirlwind I Computer No 1 7 Investigation of Atmospheric Turbulence Spheroidal r sfB Wave Functions j H8 DIST t1 AVAIL t9 ir SP'ECIAL Nq' 1 19 in 4'et'lt the lth pp ti Nut'lear Mautnolet Itoeionantip Abitoriuttion Woin Now I42 rnumty tit 14hiwk Wavom a ltw dlinpiona I it rid it voiwentratpd mnson mub joi'lp o I nlkillioy load 0 Nii 143 Vilirst tunal Ikiony Niw vii rtit f A Colwe r Cry ttaio Thono pro-tbloni were in% addil on it to longi ranle pirtibtvnipi roported In the pe itus Digital Diring July tho S KC Oresii 1evo tomd sit ritliriniiiAl c'onijimpr lgIr whichi wait witted lin a two woek Suunmo Sonesui 'e'rmo l at MIT Aktiusit 24 Soeiinmr 4 ont it led Digiital 'ont liutorm and their Applivlatiam T his ltili involvedl tho Ihymical equtipmeint tit Whirlwind I and miade time of interpretivo routines for programmeid e'itra proiaion and filatipint arititntlete eyel vi cnti log input and outtput togetther with%favilities for priogra convt'rmion mimtake rectgnitian and pi t -mortem diranoii rho ' urs ' was attended by 106 lic'roon repro monting 17 organizatitilim ACM Meeting The muanimor eifertinve of the Assoelation for C mpl uiIg Mai-hinory wao held at MIT on September 9 10 and 11 During the meeting the Digital Coniputer Lattoratory Was opemn fir lInspectitin and 230 viattorm were rororded Magmitet-CtioeMoiory A new internal high-opeed memnory utillaing magnetic vuoe ham replaced electrot Atie storitge it%Whirlwind 1 The attoraa'e capacity of the now memory ii the aaznv am the old 2048 registers but performance tests have indicated that magnetic cores will greatly reduce maintenance time am well an Increase the computer's o'perating sae 1 The next immuo of the Newsletter will contain detailed Information on the operation of thin system ABIRDREN PROVING GROUND COMPUTHRIS The ORDVAC The Ordvac underwent a thormgh overhaul in July Available machine time for the past five weeks following the overhakul has averaged 120 h ours pes week The last week In August 40 RCA Type C73376B deve lopmental type cathode-ray tubes were installed in the memory Ont the basis of early experience with this installation it appears that minimum read around ratios of 100 can be maintained This in about twice the read around ratio obtained previously The JCDVAC During ilia week ending 26 June 1953 the Edvac broke all previous records of available weekly machine time for BRL mac'hines with an available time of 159 9 hours For the past three months the Edv'ac has averaged 02 hours per week of available machine time reflecting the effect of improvements which have been incorporated into the basic machine during the past year The ENJAC Installation of the new 100-word static mnagnetic memory was satisfactorily completed The unit designed and constructed by the Burroughs Corporation increases the internal highspeed memory to 120 words and is one of the most significant improvements to the ENIAC since its completion in February 1946 It is interesting to note that the memory was delivered installed successfully tested with the ENIAC and placed in routine operation in a four-day period Operating experience with the memory to date has been highly satisfactory -3- THE MIDAC University of Michigan Digital Automatic Computer Regular operation of the MIDAC begun June 1 1953 has increased over the summer period to approximately 40 hours of scheduled operational time per week The MIDAC a general purpose digital computer patterned after the SEAC was constructed by the Willow Run Research Center of the University of Michigan under the auspices of the Air Forces A maJority of the internal orwerations about equivalent to those on the SEAC are now available Additional relative addressing' operations designed specifically for use with subroutines stored on a magnetic drum are now being checked out Construction has been under the supervision of Johui DeTurk and later Roy Hock The machine which was begun in 1951 is a serial machine using a basic clock' frequency of one megacycle The principal engineering characteristics of the machine are Word length 44 bits plus sign bit 45 total Arithmetic Unit Type Serial Type of Code Three-address Average number of additions subtractions etc sec 1 000 including four accesses to memory Average number of multiplications or divisions sec 300 including four accesses to memory Memory Type Acoustic delay line Drum Memory Capacity 512 words Acoustic 6 144 words Drum Number of vacuum tubes 1500 Number of germanium diodes 20 000 Physical Layout Packaged units Input Photo-electric reader Output Flexowriter at present During the three months of operation an interim Input Translation Program has been checked out to provide complete translation of instructions and numbers from an external decimal-aigebraic language into the internal machine binary language Upon completion of the drum and relative-addressing features this program will be extended to call in subroutines automatically and to provi utomatic code-checking and utility program features Among th# problems coded checked out or solved on the MIDAC are solution of simultaneous equations for general order n 5 17 solution of a parabolic differential equation solution of a problen in the dynamics of a large-scale economic system several data-reduction problems and sinulation of a number of large-scale dynamic systems In addition a floating point program is available for short problems where elimination of scaling procedure can save programming time The machine has been so constructed that it can be expanded without changes in the logical structure to twice the acoustic memory storage capacity and four times the drum storage capacity A special two -week Summer Program on Digital Computers - Their Application and Evaluation was held at the University of Mitchigan August 10 through August 21 The MIDAC was used as the laboratory machine for course members The course itself stressed programming and formulation numerical analysis applications and evaluation of existing commercial computers -4- A graduate course in Methods in High-Speed Computation M174 was given at the University for the first time last spring This course will be repeated in 1953-1954 as a twosemester course aimed at training for use of the MIDAC In addition a two-semester course in Digital Technology EE258 will be concerned with the design construction and simulation uses of digital computers THE FLAC During the past two months a limited computational work load has been assumed by FLAC Lack of both -oding personnel and multiple input units has delayed transfer of all Air Force Missile Test Center computations from SEAC to FLAC Several problems have been solved however including one for F J Murray of Columbia pertaining to crystal growths The final control console has been attached to tb- computer and the addition of four Raytheon multichannel magnetic tape handling units is in progress With all auxiliaries operat' i the total pow - f M'lbd by the ' ter'q power supplies is less than 7 kilowatts Since little information has been made available on the coding for FLAC the operation codes and operating times are given in Figure 1 It should be noted that the addresses specified in FLAC instruction words may be either absolute or relative hence the machine is called a floating three-address machine Further when relative addresses are employed they may be relative to either the control counter Cc which sequences the machine through its instructions or relative to a number stored in the base counter Cb The contents of Cb can be modified only by a tally instruction The terminology used in Figure I isexplained as follows a and P designate the locations of the two operands the result a P and Y designate the quantities stored in a 0 and Y The binary control digits a b c and d a- - used to indicate whether a A Y are relative i e presence of an a b or c digit indicates a relative address and the presence of a d digit indicates that the relative addresses are with i'espect to the base counter Cb These relative-address features greatly simplify and accelerate handling of iterative processes THE SWAC During the last quarter the SWAC worked on 29 different problems for a computing time of 623 hours out of a scheduled time of 845 hours A full set of eigenvalues and eigenvectars for a 32nd order matrix was computed to 10 significant decimal digits With the aid of magnetic drum memory the complete solution was obtained in 18 hours of computing tin Methods were developed for the solution of assignment problems by permutation of matrix elements In particular solutions for 8 x 8 10 x 10 and 12 x 12 matrices were obtained The solution of the 12 x 12 was obtained in 3 hours running time THE ORACLE Oak Ridge Automatic Computer The Oak Ridge National Laboratory's high-speed electronic digital computer ORACLE has passed the final acceptance tests at the Argonne National Laboratory and is at present being installed in its permanent location ORNL at Oak Ridge Tennessee The ORACLE ran successfully at ANL for approximately 250 hours solving problems with an efficiency of 92% i e 23 hours of the total available problem time were used for trouble-shooting machine failures During this time the 2048-word electrostatic memory teature of the ORACLE was utilized in solving a Monte Carlo type problem The installation at ORNL will incorporate a Ferranti photoelectric reader and a teletype fast punch in the input-output system -5- --A M fr a 4 z 0 u j t o - - g it ' 4L Xya U a- - I- I - I - aW g W z 0 u Z 1 a 1 -y z z 1- 1a f OaCR 1 ' A Ir w -u I II M 1du1 1 3U a wza u KK a4- d u u -8 C S S IGCN THE LAS COMPUTER Institute for Advanced Study Computer For the period 1 June through 29 July 1953 the Instit'ite for Advanced Study machine was in operation for 1176 of the 1416 hours in that period Of this total number of hours the machine was available for computation 1017 hours and was used or computing 920 hours i e about 90 5% of the available time Since that date the machine has been in the process of being moved from its temporary to its permanent location in the computer building at the Institute At the time of this move minor wiring changes and rearrangements have been made The new location has been planned and arranged so that it should be considerably more advantageous from the point of view of convenience of operation The machine proper is to be housed in a room by itself with the machine operators in a separate and adjoining room The manual cGntrol of the machine is to be in the latter room and has been simplified COMPUTER RESEARCH CORPORATION COMPUTERS CRC 102-A The twenty-ninth 102-A is now in production and the first training class for maintenance and programming personnel has been held for customers These classes will be held bimonthly and are four weeks in length The next class will begin October 12 A special address 2100 has been made available in the 102-A providing a zero as an operand with no access time This programming feature makes possible unconditional transfer easy transfer of information from one cell to another and a new mode of extracting provides zero test and facilitates certain logical products The Magnetic'Tape-Handling Unit an auxiliary piece of equipment for use with the 102 -A is now in production and it is expected that it will be purchased by the majority of 102-A customers The Tape Editing and Printing Unit is in final test and will be available as auxiliary equipment shortly CRC 105 Three 105 Decimal Digital Differential Analyzers are now in use Acceptance was made of a 105 on September 10 at the U S Naval Ordnance Test Station at Pasadena The 105 which has been operating at Lockheed Aircraft has according to the Matheinatical Analysis Department there 11 been in fault-free operation for 21 days 9-hour shift with an over-all availability time since the date of installation of 91% One more 105 is in the test stage for another government installation and four more are under construction CRC 107 The first 107 along with the High Speed Printer was delivered in August to the Bureau of Aeronautics Washington Final tests are being made on a similar installation to be delivered in November to the White Sands Proving Grounds The High Speed Printer part of the BuAer installation consists of a mechanical printer and paper feed and a separate cabinet containing the logical circuitry It is designed to print 120 characters per line at the rate of ten lines per second It can prepare forms paper copies and carbons or duplicating masters The printer can print 55 characters which include all the characters on a Flexowriter excepting the lower case alphabet but including 1 1- and 4 The printer is capable of handling information at an average rate of 1300 decimal digits per second with a peak of 2000 decimal digits per second IBM TYPE 701 ELECTRONIC DATA PROCESSING MACHINE The 701 is a large-scale electronic digital computer controlled by a stored program of the one-address type and utilizing cathode ray and magnetic drum types of internal storage -7- The machine operates in the parallel mode working internally in the binar input and output however may be accomplished on standard IBM cards in the Conversion between the decimal anid binary systems is accomplished by a sub does not decrease reading punching and printing speeds The 701 has a max tion time of 456 microseconds and will execute instructions at a rate of about I on typical problems Rtisults of a computation are printed on a modified IBM Ty Ing machine operating at a speed of over 10 000 characters per minute Output can taken in the form of cards punched in either the binary or the decimal system One electrostatic storage unit in the 701 can accommodate 2048 full words or 4096 half words Each full word consists of 35 bits binary digits and a sign or 36 bits in all This is equivalent to about ten decimal digits and a sign Any of the full words can be split into two half words' each having 17 bits and a sign or 18 bits in all Two electrostatic storage systems may be used to provide a maximum storage of 4096 full words Additional storage capacity is provided by two magnetic drums each having a storage capacity of 4096 full words Average access time to the drum is 40 milliseconds It is conternplated that the drums will be used for storing large blocks of information After the first word of such a block has been located the remaining words are read at a rate of 800 per second The magnetic drums will retain stored information after the power is off The 701 also has a tape-iturag ' h includes four rna grtic tape units Zatch tipe which may be up to 1200 feet long is wound on a reel The tape itself is a nonmetallic oxide-coated band one-half inch wide It is possible to store upwards of 200 000 words on each tape It takes opt the average about 10 milliseconds for the tape to accelerate to its reading or writing speed after which the reading or writing takes place at a rate of 1250 wordo per second Since the tapes are removable a library of standard programming and mathematical tables may be kept on tapes As of September 1 1953 installations of the IBM 701 which have been in operation include the following Consolidated Vultee Aircraft Fort Worth Texas Douglas Aircraft Santa Monica California General Electric Cincinnati Ohio IBM New York City N Y Lockheed Aircraft Glendale California Los Alamos Scientific Laboratory Albuquerque New Mexico IBM TYPE 650 MAGNETIC DRUM CALCULATOR The Magnetic Drum Computer was designed to meet the P ccounting and computing requirements in areas between those now served by the IBM 701 and the 604 Electronic Calculating Punch A numeric decimal machine using a self checking bi-quinary code it has a punchedcard input-output unit and a magnetic drum memory with a capacity of either 1000 or 2000 words as specified by the user A word is 10 decimal digits plus algebraic sign All of the calculator's arithmetic operations are controlled through a stored program which may be entered either automatically from punched cards or manually from the operator's console and stored in the form of magnetized spots on the surface of a drum 4 incheb in diameter and 12 inches long spinning at 12 500 revolutions a minute The calculator's arithmetic unit operates at electronic speeds It can accumulate 10-digit numbers to form a 20-digit total at the rate of 200 a second multiply a 10-digit number by a 10-digit number to develop a 20-digit product at the rate of 100 a second and divide a 19-digit number by a 10-digit divisor to develop a 10-digit quotient and a 10-digit remainder at the rate of 80 per second It has an input rate of 200 punched cards a minute and a separate output of 100 cards a minute In addition to its large numerical capacity the calculator also features a Table Look-Up' operation which facilitates the automatic searching of rate talles such as occu- in the utilities life and casualty insurance transportation and other commercial fields -8 - By means of the console the operator has control over all stages of the calculations and may manually insert Instructions or data into any desired storage location examine the contents of these locations stop the calculation at any roquired point and begin calculation with any deaired Instruction located in the memory unit THE SEAC The electrostatic Williams memory is now available for problemrs which require 512 words in addition to the 512 words of acoustic memory capacity Since the beginning of June it has been used on 45 different occasions with productive results These error-free runs ranged from about 10 minutes to 9 hours in duration Its use is now limited mafnly by the fact that most problems are coded for only 512 words of memory The acoustic memory has been provided with an odd-even parity check for all words read from memory This equipment has added to the efficiency of machine operation The computer is now powered by a set of regulated dc power supnlies the output voltages of which are varinbl Iro - the computer power panel for purposes of marginal checking In addition controllable ac stabilizers are now being used A closed-cycle air-conditioning system which is independent of the building air conditioning is provided for the computer An additional magnetic wire input-output dumper has been added to the Installation Using this dumper a code has been devised which will check-sum all but eight words of the 1024-word memory transfer the entire contents of the memory to a removable wire cartridge check the complete recording for accuracy and enable the machine automatically to resume computation all within 90 seconds During July and August 1953 average good operating time was 83 percent of total assigned time good time being defined as time during which the computer was used without error for problem solution or code checking or in which it was idle but in order The average computatlonal time per week during the June-Septemb r quarter has been 74 hours CONSOLATED MODEL 30-201 COMPUTER The breadboard of the Consolidated Model 30-201 Computer has been in continuous operation for three months as of September 8 1953 except for scheduled tests and preparation for transferring the breadboard assemblies to the prototype packaging This prototype which is near completion will remain at the Consolidated plant for engineering and application studies The first two production models of the computer will be delivered to customers early in 1954 and computing systems incorporating the 30-201 as a central unit will be available for delivery in the latter half of 1954 Print-out and control commands have been expanded by the addition of seveiai variants for further flexibility in programming and the use of interpretive subroutines has been facilitated by making the contents of the order counter available in the R register as an automatc exit point and entrance point Diagnostic routines and operational test programs have been edited and thoroughly checked The ibrary of subroutines has been expanded and in addition to the problems mentioned in the July 1953 Newsletter matrix inversion is being programmed wcnd floating-point arithmetic is available in two forms one economical of time and the other of space Development of IBM card input-output is continuing BURROUGHS LABORATORY AND WAYNE UNIVERSITY COMPUTERS The installation of a new Burroughs Unitized Computer was scheduled for completion in late September at Wayne University Detroit -9 - The Wayne Computer designed and engineered by Burroughs Corporation's engineers in the Philadelphia Research Center has been named UDEC -Unitized Digital Electronic Computer This digital computer will have been installed and In operation at Wayne University in only four months after the job was begun The primary differences between UDEC and the original Burroughs Laboratory Computer are a use of new model magnetic shift registers and u incorporation of a magnetic drum memory of 5 300-word capacity using low-level head switching techniques The new model magnetic shift register haz also been installed in the Laboratory Computer in Philadelphia and has given excellent performance The magnetic drum in UDEC was tried cut over a two-week period in the Philadelphia Computer Taking advantage of the flexibility oi the Pulse Control Units in the Philadelphia computer it was possible to install the new magnctic drum in only a few hours and later remove it in an equally short time without serious interruption to Computation Services The Philadelphia Laboratory Computer is now largely engaged in Computation Services to industry on engineering problems Among the recent computations and programming developments are included pipe stress analysis rotating disk stress am ysis servo-mechanical calculations and turbojet performance During a two-week special session on digital computers at Wayne University in August problems were transmitted from Detroit by teletype for solving on the Computer in the Philadelphia Research Center and solutions were sent back to Wayne University by teletype THE JAINCOMP-D Preliminary design work has been completed on JAINCOMP-D an unusually small extremely flexible hlgL-speed general purpose digital computer This machine will occupy three cabinets each 24-1 4 x 21-7 8 x 27-5 8 inches in size exclusive of power supply The machine will contain a 36 864-digit 1 024 36-bit numbers rapid access 3 jisec 36-bit word magnetic storage of the JAINCOMP type plus a 4 608-digit 128 36-bit numbers static punchea card random access 1 g sec 36-bit word storage for constants plus a high capacity magnetic tape storage of long ac-- time This very small computer can be programmed externally from magnetic tape or a static punched card or can be programmed from Ltorage Orders can be manipulated in the arithmetic unit Special operations such as extraction are possible The machine is basically of the three-address type although it can be programmed to be used as a four-address computer THE OARAC Aeronautical Research aboratory Computer The Aeronautical Research Laboratory formerly Office of Air Research Automatic Computer was delivered to Wright-Patterson Air Force Base in February 1953 Six weeks were required for the physical installation including air conditioning Two more weeks were required for electrical installation and checking The addition of a motor-generator set wp s found necessary to eliminate line transients Full-scale computing was under way the latter part of April The OARAC is a coded decimal single-address serial machine with magnetic drum storage of 10 000 eleven-digit words The input-output medium is magnetic tape with Flexowriter tape preparation and reading units The operating speed is about 100 operations per second at present The design has been completed for conversion to a two-address system and the addition of a high-speed printer The machine is presently operating five days a week twenty-four hours a day with one shift of engineei Ing service Since operatios began ' he machine has been available for use 1157 hours out of 1672 hours of 'on' time During the month of August the machine was operated two shifts a day In that period the available time was 270 hours aut of 327 hours of on time 10 - TiE ALWAC The ALWAC Is a general purpose digttal computer of the internmlly prorammed magnt drum type It Is a aerial binary computer with automatic conversion from deciaml-to-binary and binary-to-decimal during input and output accomplished by an internally programmed routine Recirculating working channels and arithmec registers permit high coputatloml reas as a result of the low access times In these stores Electric typewriters with associated paper tape perforating and tape reading equipmet are used as the basic input-output devices Master programs contalning numerical data to be operated on by these standard routines can be entered into the computer from the punched tap or manually via the keyboard The final results can be printed out with form control signs decimal points and alphabetical headings completely under the control of a permanently stored sequence of instructions As many as ten electric typewriters can be attached to this machine at various remote locations The magnetic drum memory consists of a 2048-word main storage a 64-word working storage 4 arithmetical registers and the clock and timing channels The words in the main storage ar arranged into 64 channels containing 32 words each Each word consists of a 22binary bit iumber equivalent to about 9 5 decimal digits with a sign digit and two check digits Additional 2048-word drums can be attached when greater storage capacity is required Each word space in the memory is divided into four order spaces called syllables and each syllable is capable of storing a command or order which the computer will carry out This compact method of storage for instructions is made possible by the system for specifying addresses for the computer Most of the commands that the machine will carry out do not require addresses therefore a great deal of storage space is saved by having addresses only whein they are needed The machine proceeds from one syllable to the next in a standard sequence in looking for its orders When it finds an order which requires an address it looks at the next syllable in the normal sequence and interprets the number located there as the address Then it will look in the next space after that for its next order The first ALWAC has been in successful operation for six months at Redondo California The second ALWAC installation will be at the Navy's David Taylor Model Basin in December 1953 The development of the computer was sponsored by Dr Axel L Wenner-gren the wellknown Swedish industrialist and the work i being done by Logistics Research Inc in Redondo California THE MONROBOT MU A new series of Electronic Calculators currently under construction to be called MONROBOT MU will soon be available In a variety of combinations theme urits possess the ability to meet a wide assortment of requirements in storage capacity operating speed facilities for input-output etc The present MONROBOT V may also be obtained with multiple input-output units including Flexowriter keyboard and perforated paper tape each individually under programmed computer control The computers are made by MONROBOT Corporation Morris Plains N J Subsidiary of Monroe Calculating Machine Co DATA PROCESSING AND CONVERSION EQUIPMENT KEARFOTT SADAC SADAC Servo-Analog-Digital-Analog-Converter was designed and built by Kearfott Company Inc Engineering Division Clifton New Jersey during the second quarter of 1952 SADAC a compact converter measuring onl 1-1 4 inches in diameter by 3-3 4 inches in height accepts analog information in voltage Lorm from a remote transmitter and converts it to digital readout in unambiguous cyclic-binary form Conversion of the analog information is made in a servo loop which except for the amplifier is enclosed in the SADAC converter A remote synchro transmitter mounted on the - 11 - shaft to be meanured furnishes an electrical indication of shaft movement to a control transformer in SADAC and any change in shaft position causes a departure from null in the control transformer A servo motor respondinr to the amplified control transformer signal neutraliles this error signal by turning the control transformer back to the null position simultaneously the servo drives a series of segmented drums whose electrical output when the control transformer returns to the null position is the cyclic binary representation of the position of the shaft being measured SADAC has a digitalilsed capacity of 212 or 4096 bits Accuracy is 02% one bit Follow up speed of SADAC Model I is 330 bits per second and readout can be either on the run or on demand SLDAC Model 2 which operates on the same basic principle is a smaller unit designed for mounting directly on the shaft to be measured so that one servo loop can be eliminated Design work has already begun at the Kearfott Company to modify SADAC for use as an inverse converter digital-to-analog as well as on a miniaturized high-speed true binary converter CCP 701 DIGITAL PODIT PLOTTER The new CCP 701 Digital Point Plotter recently announced by California Computer Products 3927 West Jefferson Boulevard Los Angeles 16 California is a high-speed lowcost digital point-by-point plotter developed primarily for preparing curves and graphs of data received from general-purpose digital computers It has an aluminum plotting drun 12 inches long and 6 inches in diameter capable of producing 11- x 17-inch plots Plotting resolution is 40 points per inch with accuracy held to 0 025 Plotting speed is 2 seconds per point A variety of stylus-symbols may be selected Sythe user An optional decimal keyboard is available for manual plotting and provision can be made to plot data from magnetic and paper tape or IBM card readers Other features include automatic multiple curve plotting arbitrary origin location scale factor trim adjustment a swing-out chassis rack for easy accessibility to component parts plug-in components and a choice of type of digital input system SOLID ACOUSTIC DELAY LINE MIMORY UNIT Additional information has been received concerning the memory unit Model 3C1-384 mentioned in te July 1953 Newsletter which was developed by the Computer Control Company The design includes the entire memory circuit in one plug-in type chassis Figure 2 ready for installation in a computer Groups of these units are used in a computer to provide sufficient memory A complete mamory circuit can easily be removed for servicing and a spare unit plugged in to keep the computer operating The unit stores 384 bits at a pulse repetition rate of 1 Mc A self-contained heating element and thermal control gives temperature stability to the quarts line Inherent accuracy of delay control greatly exceeds design requirements All germanium diodes are grouped in a single plug-in type subunit All five tubes are 6AN5's operated 80% below manufacturer's design center The over-all dimensions of the plug-in chassis arc 4-1 2 x 5-1 2 x 10 inches A self-contained filament transformer is optional The input voltage requirement into write-erase gate is 10 volts The reshaped output signal level is 15 volts into a 100-ohm impedance load Carrier frequency is 20 Mc All circuits are degenerated with reserve gain in the wide band L f amplifier There is a gain control for initial adjustment of the L f stage No tuning is necessary The temperature coefficient of the quartz delay line is -128 parts per million per degree centigrade The unit is especially fitted for airborne use and is insensitive to shock - 12- Figure Z - Solid acoustic memory unit MACDONALD MAGNETIC STORAGE DRUMS The W S Macdonald Co Inc 33 University Road Cambridge 38 Mass originally designed a magnetic drum for the Magnefile electronic office equipment of the Company's manufacture It is now offered as a separate unit for those requiring data storage of the drum type This design and modifications thereof are available in several standard sizes where a standard size or capacity of memory will not meet the user's requirements other sizes can be furnished within rather broad limits The magnetic storage drum consists of an aluminum or magnesium ingot which is mounted on ball bearings and driven by a belt or direct-coupled electric motor One drum type features a moving head which travels on machined ways parallel to the axis of the drum and at constant spacing from the drum surface Heads which are adjustable in respect to drum clearance but fixed in their lateral position may be supplied in addition to the moving head or in place of this head All heads are normally operated out of contact with the drum surface The magnetic storage medium of the drums consists of the red oxide of iron applied to the drum surface as a coating of high uniformity POTTER MAGNETIC TAPE HANDLZR The Potter Magnetic Tape Handler Models 901A and 901B is an instrument for intermittent or continuous recording and playback of digital information Figure 3 High-speed starts and stops in either direction within 5 milliseconds controlled by external signals and dual-speed tape drive provide the facilities for all types of high-speed recording sorting collating comparing and processing of any data which can be expressed in digital form Tape drive is independent of the reel drives and symmetrical with respect to the recording head to provide uniform tape speed in the forward and revers directions and to assure optimum compliance on all recording tracks Independent proportional photoelectric servos for each reel maintain proper tension and completely eliminate breaking or spilling tandard NAB 10-1 2-inch reels provide a tape capacity of 2400 feet - 13 - Figure 3 Potter Magnetic Tape Handler LIST OF COMPUTING SERVICES Key a b c d Name and Address of Contact Facilities and their Location Coding and Mathematical Services To Whom Available 1 Wayne University Computation Laboratory a A W Jacobson or Z P Little Wayne University Computation Laboratory Detroit 1 Michigan b Burroughs Unitized Digital Electronic Computer and a Differential Analyzer c Available d No restrictions 2 Remington Rand Inc a Remington Rand Inc 1615 L Street N W Washington D C b UNIVAC with auxiliary equipment located at Remington Rand Inc 315 Fourth Avenue New York 10 N Y c Complete coding and mathematical service available d No restrictions on utilization 14- COMPUTER COURSES WAYNE UNIVERSITY COMPUTATION LABORATORY Six academic courses in machine computation are being offered during the tall semester These include numerical analysis design and application of analogue and digital computers pulse circuitry and physics of solids as applied to computers A program of study and research leading to advanced degrees in computational analysis is available Several fellowships in machine computation are being sponsored by industry COMPUTER RESEARCH CORPORATION Computer Research Corporation will conduct its Operation and Maintenance of the 102-A Courses on the following dates October 12 to November 4 1953 and November 23 to December 18 1953 Courses for the year of 1954 will be announced later both for the CRC 102-A and CRC 105 NOTICES NEWSLETTER TO B3 REPRINTED IN JOURNAL OF ACM Beginning with the January 1954 issue the Digital Computer Newsletter will be reprinted in the newly established Journal of the Association for Computing Machinery which will be distributed to all members of the ACM Prospective members of ACM or nonmembers desiring to subscribe to the Journal should write to the Association for Computing Machinery 2 East 63rd Street New York 21 N Y Distribution of the Newsletter to agencies of the Federal Government and Federal Government contractors will continue as before Non-government addressees who have remained an the distribution list through this issue will no longer receive the Newsletter from government distribution JOINT COMPUTER CONFERENCE Statler Hotel Washington D C December 8-10 1953 ' Information Processing Systems - Reliability and Requirements is the general theme of the Joint Computer Conference sponsored by the Institute of Radio Engineers the Association for Computing Machinery and the American Institute of Electrical Engineers to be held December 8-10 1953 at the Statler Hotel Washington D C Mr Mark Swanson Chairman of the local committee on arrangements has announced the completion of plans for all Important aspects of this Conference Mr L R Johnson vicechairman in charge of registration stated that present interest in the Conference indicates an attendance of at least 1600 persons Dr Howard T Engstrom chtirman of the technical program committee reports that arrangements have been fInalized for the following presentations sa December 8th Morning Address of Welcome John H Heward Burroughs Corporation - 15 - Keynote Address' Howard T Engstrom Remington Rand Inc The RTMA Support of the 1950 Computer Conference - A Progress Report Thomas H Briggs Burroughs Corporation The Use of Electronic Data Processing Systems in the Life Insurance Business' M E Davis Metropolitan Life Insurance Company 'Computer Applications in Air Traffic Control Vernon I Weihe Air Transport Association of America Afternoon Data Processing Requirements for the Purposes of Numerical Weather Prediction Joseph Smagorinsky U S Weather Bureau 'Methods Used to Improve Reliability in Military Electronics Equipment' L D Whttelock Bureau of Ships Digital Computers for Linear Real-Time Control Systems m Ralph B Conn Jet Prop Lab Calif Institute of Technology Wednesday December 9th Morning Reliability Experience on the OARAC Robert W House Wright-Patterson Air Force Base 0Operating Experience with the Los Alamos 701 Willard G Bouricius Los Alamos Scientific Laboratory Acceptance Tests for the Raytheon Hurricane Computer Professor Francis 1 Murray Columbia University Reliability of a Large REAC Installation' Bernard D Loveman Reeves Instrument Corporation 'National Bureau of Standards Performance Tests' S N Alexander and R D Elbourn NBS 'Experience on the Air Force UNIVAC Robert Kopp Headquarters U S Air Force Afternoon 'Electron Tube and Crystal Diode Experience in Computing Equipment' J A Goetz and H X Geisler IBM Corporation 'Reliability and Performance of the ILLIAC Electrostatic Memory' Joseph M Wier University of Illinois 'Electron Tube Performance in Some Typical Military Environments' D W Sharp Aeronautical Radio Incorporated - 16 - Thursday December 10th Morning SEAC - Review of Three Years of Operation R A Kirsch and P D Shupe Jr NBS A Review of ORDVAC Operating Experience Charles R Williams Ballistic Research Laboratory Some Remarks on Logical Design and Programming Checks' Herman H Goldstine The Institute for Advanced Study The Advantages of Bilift-in Checking' John W Mauchly Remington Rand Inc Recent Progress in the Production of Error Free Magnetic Computer Tape W W Wetzel Minnesota Mining and Manufacturing Company Afternoon reliability of Electrolytic Capacitors in Computers Mark VanBuskirk P R Mallory and Company Inc 6A Method of Reliability Specification and its Application to Transistors' W J Pietenpol Bell Telephone Laboratories Case Histories in Resistor Reliability Jesse Marsten International Resistance Company The MIT Magnetic-Core Memory' William N Papian Massachusetts Institute of Technology Discussion of these papers will occur both in the sessions themselves and in additional sessions to be held solely for the purpose of discussing topics of unusual interest Miss Margaret Fox vice-chairman for inspection trips has completed arrangements for visits to various computer installations in the Washington area All registrants will have the opportunity to Indicate which inspection trips they prefer to make Mr L D Whitelock vice-chairman for exhibits has prepared an unusual arrangement for demonstrators at the Statler Hotel A unique feature of this arrangement provides a large uncongested area so that all parties will be able to view exhibits specially arranged by outstanding manufacturers Preliminary announcements have been mailed to all members of the sponsoring organizations The final program and applications for reservations are now being processed for the same mailing list Interested parties who are not members of any one of the three sponsoring organizations may request the final program and reservation application from Mr L R Johnson 2018 Sycamore Drive Falls Church Virginia JOINT COMPUTER CONFERENCE PUBLICATIONS AVAILA BLE A limited number of Joint Computer Conference Proceedings are available from ALEX IRE and ACM at the prices listed below These Proceedings provide a compreensive sourct of information in the field of electronic computers Many organizations are using them as textbooks for courses on computer design and application and for the instruction of new employees Orders should be sent to R S Gardner American Institute of Electrical Engineers 33 W 39 Street New York 18 N Y L G Cumming Technical Secretary The Institute of - 17 - Radio Engineers 1 East 79th Street New York 21 N Y or R V D Campbell Treasurer Association for Computing Machinery c o Burroughs Corporation 511 N Broad Street Philadelphia 23 Pa Content Publication Price Joint AIRE-IRE-Computer Conference Proceedings Published Feb 1952 REVIEW OF ELECTRONIC DIGITAL COMPUTERS Papers and Discussions presented at the Joint AIRE-IRE Computer Conference Philadelphia Pa Dec 10-12 1951 114 Pages $3 50 Joint AIZE-IRE-ACM Computer Conference Proceedings Published March 1953 REVIEW OF INPUT AND OUTPUT EQUIPMENT USED IN COMPUTING SYSTEMS Papers and Discussions presented at the Joint AIEE-IRE-ACM Computer Conference New York N Y Dec 10-12 1952 142 pages $4 00 Joint AIlE-IRE-ACM Computer donference Proceedings Published June 1953 PROCEEDINGS OF WESTERN COMPUTER CONFERENCE Los Angeles Calif Feb 4-8 1953 Twenty-two papers and discussions on computers and their application 231 pages $3 50 DCN NEWS ITEMS The Electronics Branch of theOffice of Naval Research Washington 25 D C solicits news items for inclusion in the Digital Computer Newsletter Material should be received by 10 March 10 June 10 September or 10 December for publication in the Newsletter for the following months - 18-