|
|
Computer Programmer, Systems Analyst, Junior College President
and
Expert on the Kenbak-1, The World’s First Personal Computer
Circa 1971
June 20, 2003
This is a story concerning my Electronic and Computer background. I feel that this portion of my background should be documented because of certain historical contributions I have inadvertently made and experienced in the field of Personal Computers, and Microprocessors. It is hoped that appropriate recognition will be afforded to my hometown, Charleston, South Carolina, the Kenbak-1, the "World’s First Personal Computer, its inventor, John V. Blankenbaker, and the Electronic Instructors that passed on knowledge of computer technology to hundreds of my students, most specifically, Keith Vorhis, Academic Dean and Gary Crozier, Digital Electronics and Microprocessor Instructor.
I was born in Berkley County, South Carolina on July 4th 1933. My home town is Charleston, S.C., and I resided there or close by, most of my life. This story could only be written through the wonderful support of my wife of over 50 years, Dorothy and our three children. In one way or another they have all been instrumental in helping me develop my schools and the Junior College I presided over for more than 35 years.
Charleston, is touted as "America’s Most Historic City" and it is known for a myriad of historical "firsts". The most noted, is that Charleston was responsible for firing on "The Star of the West", and The Civil War began. We hope to add to the historical firsts of Charleston and will use this paper to explain how we intend to do it. Briefly, Charleston had a junior college, Nielsen Electronics Institute, that taught students how to program the worlds first personal computer, the Kenbak-1. The college graduated hundreds of students that were taught basic computer programming and the electronics concepts of computers using that magnificent computer training device. It took a few years to make that discovery, because Personal Computers would take years to evolve. Who could be given credit for the first Personal Computer was a mystery until 1986.
Only when the Boston, Computer Museum started a contest to determine exactly what early computing device could be considered the world’s first personal computer, was the mystery unraveled. According to, "The Computer Museum Report, Volume 17 — Fall 1986, advertisements went out worldwide from October 1985 to March 1986, designed to solicit old machines for the purpose of analyzing them and measuring them against pre-determined standards specifically developed to make such a determination. According to the report, the heading of the ad ran — "Wanted: Old Thinker-toys". Offers flooded them from 13 countries, vying for recognition.
The report indicates that over 320 entries were received. A panel of judges prescribed the criteria needed to measure if an electronic computing device qualified as a Personal Computer. A total of 137 items were reportedly accepted. The judges were, according to the report, Stephen Wozniak, designer of the Apple II and co-founder of Apple Computer, David Bunnell, an early MITS employee, current publisher (1986) of PC World, and Oliver Strimpel. (Oliver Strimpel is specifically included, as he referred to himself in the report I am referencing). Only after searching worldwide did they make their decision that the Kenbak-1, designed, built and marketed by, John V. Blankenbaker in 1971, through his California based, Kenbak, Corporation, qualified as the "world’s first personal computer". Very little was published in that report about the Kenbak-1, and I hope the material presented here will further enhance its history. This is a history about the Kenbak-1, when it was actually used by students, in a highly productive way as they earned the Associates Degree in Electronics Technology. This is the only known instance where the Kenbak-1 was used commercially to train students in a school or college.
Before we get into my background concerning the Kenbak-1, which is dwarfed by the inventor, John V. Blankenbaker, lets review some information he recently supplied me. John wrote on June 3, 2003, - "Born in 1929. Tried to design a computer when freshman in college (Oregon State University) in the winter of 48/49. Worked in the computer department of the National Bureau of Standards in 1951. Started work for Hughes Aircraft Company in 1952. Designed arithmetic unit for business computer there. Envisioned a simple computer described in "Logically Microprogrammed Computers" in Computer Transactions in 1956 or 7. Worked at Quotron (stock market quotations). Started design of Kenbak-1, in 1970 as a private endeavor. Incorporated, built, and sold about 40 odd Kenbak-1, computers before selling out to CTI Ed. Products. Other activities after that and retired in 1985. Now, I research the first German communities in Virginia and write about them."
For you to accept me as being competent to tout the power of the Kenbak-1, I think it is necessary to explain that I am not the "run of the mill" teacher in Computer Science. My experience with electronics, IBM data processing equipment and computers, reaches far and wide. It has been a major part of my life. I hold the record for highest score in the U.S. Air Force on passing their Data Processing Examinations. As an enlisted man, I also had command of the data processing section in Myrtle Beach, S.C., until they could staff it with a qualified Data Systems Officer. I did not have the rank, but I had the authority. I answered to a full colonel in the Tactical Air Command in Sumter, S.C. I instructed Air Force Officers and Enlisted men in the use of data processing equipment while in the U.S. Air Force for several years.
When IBM was broken up by the Anti-Trust Act, I opened one of the first (IBM) data processing schools in the country (1960) in Fayetteville, N.C. and another in Greensboro, N.C. (1962).
I expanded my school in Greensboro N.C., Data Systems Center, Inc. and began to service schools and colleges that wanted to offer data processing courses. I operated in several states. They would make the offering, I would provide the equipment and instructors. After they learned of the profitability and interest in those courses, they contracted with IBM for the equipment and hired or trained their own faculty to teach the IBM equipment courses they offered. Schools began to offer Data Processing courses all over the country. Later, when the solid state, IBM 1401 was announced, courses in computer programming were offered. Because it broadened the programming abilities of programmers, some schools included a little "Systems Analysis and Design" in their course offerings.
One of my major customers was Palmer College of Charleston, S.C. I implemented an Associates Degree, course in data processing for them. The course was accredited by the Accrediting Institution for Colleges and Schools (AICS). Palmer College is now a public institution in Charleston, S.C. During that same time, I opened the first Service Bureau in Charleston, Data Processing, Inc. (1964). The service bureau needed software that was unavailable at the time. I designed and programmed it. For the most part, the term "Software" insofar as used by a common computer programmer, meant an Assembler, or Compiler Program that would take "readable operation codes" and convert them to the "numeric code" that could be fed into computers to become a "program". Behind the scenes, software worked completely independent of the common Programmers, and the "specialized" Programmers that wrote programs to support common Programmers and their work permitted the "easy" use of Printers, Card Punch Machines, Card Readers, Magnetic Tape, and Disc Drives, etc., must be acknowledged. I suppose they were the "world’s first Software writers". The Service Bureau, used the Burroughs, B-260, with dual card readers. Because they did not have the ability to "collate" information, I was forced to write the Software program to support that function. Burroughs Computer Co. used the software I invented for servicing their other customers. The service bureau also had a full complement of IBM machines.
I was a Systems Analyst and Data Systems Officer for the Army Material Command (AMC). I was nominated for and placed in the AMC "Executive Talent Bank". I was the youngest executive in it, at 35 years of age. That bank assures that the United States Army will have sufficient executive management to continue operations as other executives retire, die or leave for other reasons. I considered it a high honor to be entered in that program. Because of my Civil Service rank, I was issued orders, from time to time, as the Acting Base Commander of the Charleston Army Depot, North Charleston S.C.
I opened Nielsen’s IBM Training Center in Charleston, in 1962. It remained open while I worked for the U.S. Army Depot. When I resigned from the Depot, it eventually became Nielsen Computer College (1970). The College was then operating at 1600 Meeting Street, in Charleston. I produced some of the finest computer programmers this country has ever experienced. Before I could afford my own computers, I would contract with local companies that had the IBM 1401 — they normally had about 2K of "Core Storage" memory. During that time, we taught the NCR 500 (programmed in absolute code) NCR Century 100 with two disc drives (Compiler) and the IBM 360 (Assembly Language & Report Program Generator). Unit Record IBM machines were also taught to produce qualified Data Processors. That included: IBM Card Punch, 024 & 026 and the IBM verifier, 056 — The IBM 082 & 083 Sorting Machines, IBM 552 & 557 Interpreters, IBM 514 & 519 Reproducing Machines including the "Mark Sense" feature — IBM 403 & 407 Tabulator/Accounting Machines and the IBM 602A & 604 programmable calculators. The usual business requirements for programmers was also taught, such as, accounting. Of major importance, was the normal automated business systems, including payroll with its complicated variety of employee payment methods, inventory control, cost analysis, accounts receivable, accounts payable and the production of automated financial statements.
For those of you who have never attempted to actually program a computer, you should know that computer programmers, must have a special aptitude. The standard test that was used in the past by IBM to make that determination was a test published specifically for that purpose by the Psychological Corporation of America. That test was administered to each candidate wishing to learn programming. Because usual business requirements were not as stringent as they were for IBM, I modified the test. I placed a major emphasis on, and concentrated on the candidate’s ability to think "logically". If they failed the modified test, programming a computer was out of the question for them. The test was very difficult and incorporated identifying a myriad of symbols that were turned in every conceivable direction. An example would be provided of a symbol and a change was made to it. The candidate was asked to identify a completely different symbol that had the exact treatment and change as in the example and was required to select the answer from four symbols, each with similar and confusing treatment. There were also extremely long number sequences. A sequence would be provided and with different numbers, the candidate would have to select a sequence out of several sequences that would "flow" as the example flowed.
The college evolved into Nielsen’s Incorporated dba Nielsen Electronics Institute (1973). It became accredited through the National Association of Trade and Technical Schools. The change came about because I purchased the Mt. Pleasant, S.C. branch of the Kentucky based, United Electronics Institute. At that time they were one of the largest electronics technical institutes in the United States, with a wide range of campuses. The Junior College offered the "Associates Degree in Electronics Technology". Digital electronics was new and changing rapidly. I upgraded their program in "Digital Logic". Because of that, I allied myself with Consulting Technologies Industries, Education Products, Inc. (CTI) of Mt. Pleasant SC. They had a brilliant staff and the school soon implemented "LASER Vision" where video was transmitted by LASER rather than conventional microwaves. Other than Stanford, I had the only laser vision laboratory in the country.
So much for my related background to computers and electronics technology prior to getting involved with the Kenbak-1. Anyone that has not fully investigated the design of the Kenbak-1, will never understand, or come to the full realization of the accomplishment John Blankenbaker made when he designed and produced it. One must keep in mind as the Kenbak-1, is explored, that it was designed and built using Small Scale and Medium Scale integration — the microprocessor was not yet invented. Without the advantage of a microprocessor, he designed and installed on a Printed Circuit card (PC card), the complete computer, save the power supply and input/output devices used on the console. He accomplished this extraordinary feat in 1971 and began to market the world’s first personal computer. The Kenbak Corporation only sold 40 computers and because of that he would have to sell out and close the doors. Simply because he only sold forty is no indication that the Kenbak-1, was a failure. On the contrary, "computer wise" it was extremely effective and was used for over 15 years in my Junior College. That is what this paper is all about.
Because of my status as President of, Nielsen Electronics Institute, I had an opportunity to "preview" numerous digital devices for Consulting Technologies, Inc., (CTI) of Mt. Pleasant, S.C. They bought out the electronics training devices that Philco Ford formally used to train, United States armed forces personnel in electronics technology. CTI’s offerings were very wide and also consisted of Digital Electronics, the technology employed in computing equipment at the time. Digital electronics was advancing extremely fast. Each time they would consider putting a digital device into their product line, I would work with it and give them my opinion. Until the arrival of the Kenbak-1, all other devices I investigated would only perform a single step in the architecture of a "full blown" computer. As an example, using pre-wired computer "gates" consisting of And, Or, Nand, Nor, Exclusive-Or, etc., the technician would be required to assemble the "gates" via "jack-plug" wires, to make a complete digital circuit. Full adders — Half adders and Arithmetic Registers could be assembled and tested, because lights on the console would confirm proper circuits, or in some cases, volt meters would give a (+) or (-) reading. As I recall, building the Central Processor Unit (CPU) was out of the question at that time. The CPU controls all actions needed by the computer to manipulate instructions and data to ultimately produce the desired, programmed result. It is the most complicated unit within a computer.
Obviously, an economical student "computer trainer" that would contain all the features of a full blown computer seemed out of the question at that time. However, Integrated Circuits, ICs were in production and in only a short period of time a working "personal" computer was destined to make its debut. It did in 1971, under the name of Kenbak-1, designed by John V. Blankenbaker. Its name extracted from the middle of John’s last name, Blankenbaker. I learned from John, in June 2003, that he actually built the Kenbak-1, in a corporation he founded in Los Angeles, California. In his Email reply, he wrote that he designed his computer from scratch, did the layout work for his Printed Circuit card (PC card), and hand soldered the components to the PC card on many of his computers. He also acknowledged that all the components were taken off the shelf. The cabinet of the Kenbak-1, was also a stock item. He wrote that the operating speed was very low, about 1 MHz. John also confirmed that he sold out to CTI.
When CTI Educational Products, Inc. of Mt. Pleasant, S.C. got their shipment of Kenbak-1, materials in, there were about eight or ten fully assembled Kenbak —1 computers, several PC cards (the term mother board was not coined at that time), Console face plates, complete with input keys, output lights and switches, completely wired and ready to attach to the mother board. Back panel, power supplies were complete with the fan in place, also ready for attachment to the PC card by a simple plug connection. There were numerous, blank PC cards, front Console plates, fans, assorted "sleeves" of Integrated Circuits, the tops and bottoms of, pretty blue cabinets, shiny steel handles, "spacers", screws, bolts and the little rubber "feet" which would eventually be attached to the bottom of the Kenbak-1. Everything was present to put a Kenbak-1 together. It appears that John sold out to CTI and that included everything, "lock stock and barrel". In any event, CTI gained control of it and as soon as they did, (or before) I was contacted to examine and express an opinion on it as an educational product. At first I was skeptical. Not until I began studying the training manual, which described the computer architecture and the instruction set, did I really become interested.
When CTI got their shipment of Kenbak-1 materials in, (either before or after the purchase) several Kenbak-1, computers were already assembled. Because of that, I feel very strongly that I have one or more computers that John V. Blankenbaker actually put together personally. If such is the case, I consider them invaluable. In view of the fact that there are only ten (presently known about) out of forty sold, the chances that I have one or more is quite possible. I am absolutely certain that CTI never built a Kenbak-1, computer from scratch. I do not believe the sold any, other than to me.
I was present when they were working on a "jig" to attach components on a blank mother board, but the project was never completed. I viewed their production concept. Their plan was to develop the "jig" and apply a specific methodology for soldering the correct components into the proper place. Later the supervisor would train production line employees how to do the same job. When I was examining the manufacturing procedure, the supervisor had the electronic schematics at her side. In spite of my efforts to assist in marketing, the salesmen failed to convince educators to purchase the Kenbak-1, the manufacturing project was never brought to fruition. Because the electronics field was advancing very rapidly, the older, Philco Ford training devices were fast becoming obsolete, without an infusion of more advanced electronic trainers, CTI was destined to go out of business and they did. However, that has nothing to do with the performance of the Kenbak-1. It was dong a fine job for me and the capable instructors, whom I taught its power to. We had a job to train Electronic Technicians about computers, and we did, oblivious to the fact that we were also using the world’s first personal computer to do it. Amazingly, it served it purpose into the 1990’s.
The Kenbak-1, had no "plug" wires, like most other trainers, and everything was concealed in the cabinet. In comparison to other digital or pseudo computer trainers, it looked rather "naked". The architectural design really caught my attention and it didn’t take me long to write a small program, using the Operation Codes in the manual. The manual also had an exhibit, explaining by "flow chart" how to input programs. I followed the "Operators Flow Chart" and was able to enter a simple "counting routine". With the use of the manual, it was pretty easy to actually program the routine, enter it, read it back for accuracy, lock it in memory and upon pressing Start, run it. I thought the speed was excellent, considering the fact that it was a "programmable computer". The memory was sufficient to count up to 377 octal, or 256 binary and the sequence would start over. To state it lightly, I was amazed! When the Kenbak-1, was running, the console looked exactly like that of a Main Frame computer in action. When I asked John if I was correct and that his design emulated a Main Frame Computer he wrote, stating that, "Not in speed. Except for the lack of interrupts, it could be compared to much larger computers. The memory was very small and the speed was very slow". In my mind, I had to ask, "what more could John have hoped for, considering the fact that his computer was built from chips available off the shelf"? John also stated, "I designed the Kenbak-1, from scratch by myself". He also indicated that he still had a set of the original schematics. The PC board was magnificent in its design and John shared the fact that it was also designed by him. Everything inside the cabinet was a perfect fit. There was space above and below the PC mother board to allow air to circulate for cooling. The power supply was attached to the back panel and a fan, also attached to it assured that the components were kept cool. Its Console was the front panel. The design was amazing. Only a small amount of space would be required for students to use the Kenbak-1 and refer to the training manual at the same time.
As I recall, I next entered a number in memory, matched it and "branched/jumped" into a subroutine to automatically stop the computer. Using the Console, I could verify the match visually. I also discovered that I could modify or trouble shoot the program with ease because of its design. Its power was explored in depth and it had "programmable power". Although the manual describes many programs and provides the code for them, I preferred to write my own logic (flow chart) and code it. I was no stranger to the advantages of "Assembler Software" and "Compilers". I designed a system for the Kenbak-1, that would allow for writing Symbolic Programs and manually supplying the Operational Codes and variables once the Symbolic Program Coding Sheet was complete. The Kenbak-1 had its first "Compiler". After coding, the programmer only had to insert the actual code on the same line with the symbolic code.
After having the Kenbak-1, in my possession for about a week, I called a conference with the President of CTI to give my report. During that time, I explained that they truly had a small copy of a Main Frame computer in their possession. The words, "Personal Computer" had not been coined yet. The only missing devices were "automatic data readers" and "automatic data output devices". I explained what I considered to be "real" computer architecture and asked if they would like to see me give a demonstration consisting of entering and running a program. They were extremely excited, and we arranged a time for the demonstration. In just minutes I had explained everything necessary for them to follow me as the program was entered, read back, and "Run". After that demonstration, I believe they were convinced to engage in business with John Blankenbaker. Later I was asked to put on a training seminar for a group of salesmen.
It took time to schedule the sales staff, as CTI was operating nationwide. Later, when the salesmen were all gathered up in Mt. Pleasant, South Carolina, I programmed a very simple "counting routine" into the Kenbak-1, for them. I explained many of the features of the Kenbak-1, and answered questions in detail. The next demonstration was taped on video by CTI. I remained with the salesmen long enough for them to enter their own counting routine and run it. In that meeting, the salesmen were ecstatic about having such a powerful training device available to them for marketing. I was invited to join them in a "celebration" at a local restaurant. The Kenbak-1, was the topic of conversation for hours. Later, CTI provided the salesmen with a copy of the video so they could practice at home with their Kenbak-1, Demonstrators.
I learned at that initial presentation with the CTI sales force, that their "job" of making a proper demonstration to educators was going to be difficult. Although they were extremely competent as electronic technicians, that, in no way qualified them to put on understandable computer presentations. Some salesmen had the necessary "aptitude" to program a simple problem into the computer and others did not. It occurred to me that as they made their demonstrations, some educators would not have the required aptitude and fail to grasp the subject matter, others would catch on quickly, provided the salesmen did a good job in presenting it, and that was doubtful. It was a small "Main Frame" and to fully comprehend it, one required the same programming aptitude needed by common programmers. Because of my experience with hundreds of Computer Science Students, I assumed that some salesmen and school teachers would be unable to grasp the necessary concepts. I was correct in my assumption. Because of the inability by educators to grasp the concepts, I believe their personal "job security" entered the picture and sales were inhibited because of that. Only forty were sold. Of the forty sold, I purchased eight.
Unknown to CTI they had acquired the world’s first "Personal Computer", Kenbak-1. As time has proven, no one knew the Kenbak-1 was the first Personal Computer until, 1986! It was sold to them by John V. Blankenbaker, the inventor. The name of the computer was extracted from the middle of the inventors name (Blankenbaker). I was asked to analyze its potential as a marketable product for schools and universities. I was so impressed that I touted its potential to allow hands on programming of a solid state computer. At that time I was no stranger to computers and knew what I had in my possession. The Kenbak-1, was programmed not only in absolute, but the "Binary Code" and each Instruction Element had to be individually entered. Because of that, students could become familiar with Pure Binary, Hexadecimal and Octal. Octal is much easier to handle than Hexadecimal. Using the input/output lights made it possible to demonstrate Binary Coded Decimal. I knew immediately that it would soon be employed in the Electronics Technology course of my Junior College. I also knew that I had a big job ahead of me in preparing electronics instructors that had only worked with bits and parts of a computer, to eventually learn all about it and teach it to my students.
My Kenbak-1, computers were not used to teach Computer Science. The college had NCR and IBM, Main Frame computers to accomplish that. The Kenbak-1s, were employed in the Electronics Technology Associates Degree program to familiarize Electronic Technicians with the operations and architecture of computers so they would be able to understand their duties if they became employed by main frame computer manufacturers or found work in industrial environments using the new "micro" technology that was gaining momentum. Once again, aptitude became a problem. Our electronics technicians were not screened for the necessity of a "programmers" aptitude. Most left with a small understanding of computers but that was sufficient to reinforce our "Digital Electronics" phase of the training. The Kenbak-1, gave them a chance to visualize all of the components, their connections to one another, timing, power supply, cooling system, etc.
The Kenbak-1, was a "staple" in the Electronics Degree program for many years because of the many features it contained and are still in use by modern computers. I paired up two students to a Kenbak-1. One student would have better aptitude than the other, and became an advisor to the less competent one. Using that system, each technician (pair) had a "dedicated" computer to, program, troubleshoot and otherwise learn on. Remember, at the time, Main Frame Computers were extremely expensive — it was impossible to turn one of them over to student technicians. The Kenbak-1, was a marvelous computer training aid. Not until companies like Heath Kit began to make PC computer training devices was it discontinued. Even then, it was difficult to visualize the operations of the CPU in them. The Kenbak-1, had the ability to bring all data and registers to the front of the console. It could also be "Single Cycled". In other words, each individual step in the computer could be executed and observed, one step at a time.
Over the years and because of their frequent use our Kenbak-1, computers began to heat up. It appeared that because of the large quantities of small chips it was made up of, the heat generated was causing intermittent failure. We did notice that Blankenbaker designed the mother board with the chips separated from each other as far as possible, keeping with the small design of the computer. Keep in mind these little computers were in use by us for many years. The chips were readily available off the shelf and when some "failed", they were replaced but soon after, others failed too. We decided to increase the ventilation inside by drilling three small holes in the rear corners of the cabinet tops. That corrective measure was successful and the added circulation of air prevented any further chip failure.
The console had a row of "no bounce" keys, protruding from it. Entering programs or data was done by pushing "in" the key toward the metal plate making up the foundation of the console. For nimble fingers, the key action was extremely smooth and with some experience, programs were quickly entered. The contents of various registers could also be "Read". The operator simply entered the address desired to be read, pressed "Read" on the console and the console "display lights" indicated what binary information was at the requested location. Some students had a rather "heavy hand" when pressing in the "no bounce entry keys". If one of them became broken, it was a very delicate task to remove and replace it, however we accomplished that feat until we ran out of "keys". We experimented on one Kenbak-1, by replacing all of the keys with a no bounce toggle switch. It only toggles, when flipped down and it engages only for a brief time. That machine is still in working order, however without the row of "black and white" keys, its character has changed. It is still a working model of the Kenbak-1, in all other respects. The toggle switches appear to be more durable than the original keys. Perhaps they were unavailable at the time of the Kenbak-1s, design.
Electronic Technicians were programming "stop lights" using a Programmable Logic Array (Logic Gates built into a system whereby they could be connected, based upon the desired output) to perform the logic needed to sense automobiles in a reluctance loop, count and determine the length of time to hold a light green, then "time" the caution light, and switch on and hold the red light "on" for a predetermined period of time. Similar procedures were employed in factories to control industrial functions. With the advent of the Microprocessor, which was Medium Scale Integration, they had to be programmed in Absolute, but a Key Board was available to enter the code. Technicians had to learn the basics of a "Computer Central Processing Unit". Memory had to be understood, as well as the "Instruction " and "Execute Cycle". The feature for "Branching or Jumps" into "Sub-routines" and "Registers", including "Arithmetic Registers" and "Index" registers needed to "Alter" Instruction within the program needed to be understood. The "Computer Clock" definitely needed to be understood and the "cycle time" to process specific instructions was needed to control precise timing routines. I quickly recognized that the Kenbak-1, could simulate all those functions.
Understanding an "Output" and the variables under which a computer could provide one was required by technicians, because that would be the ultimate "communications" with the "out side world". The Kenbak-1, was the perfect machine to learn about all those things. Exposure to the Kenbak-1, provided enough for Electronic Technicians to get a grasp of the "stand alone" MSI Micro that replaced "discrete circuit" logic consisting of transistors and in some cases vacuum tubes that were in use where heat was a problem. In usual cases the input is received in industrial applications from an external sensor. That was the equivalent of entering a "digit" via the console keys of the Kenbak-1. The "output" derived from the program in a Micro is used to drive "mechanical relays" whereby high amounts of voltage may pass to "stimulate" heavy duty electrical motors, or pneumatic or hydraulic devices to perform robotic tasks. The "output" lights emulated that function on the Kenbak-1. One may remember the Intel 8080. As time passed, Large Scale Integration, improved the Micro’s and various systems for entering code were developed. Now, we have a computer on a "chip".
If one takes the time to analyze the power John Blankenbaker designed into his Kenbak-1, they would truly be amazed to learn that he incorporated a complete computer with everything needed to process data, except speed, a larger memory, output signals to drive printers, record on magnetic tape or discs rather than "lighted outputs" on the Console, which were great to get a "visual view" of the outcome of the program’s action. Those output lights also gave the programmer an opportunity to see his code and make corrections, prior to entering it, and to "read back the program, step by step to assure accuracy". To prevent the program from being disturbed, the Kenbak-1, could "Lock" it in place. The only Input would then be the Variable Data needed to be "Fed" the program. One had only to release the "lock" to perform that function. Once the program is entered, the Kenbak-1, performs all internal computing functions we use today, save the need for interrupts that John Blankenbaker mentioned. Naturally, it is slow in speed because of the time it was built. Its limitation is only "memory", "fast input" and "output to other devices". In all other respects, it is a "Computer". It is small, portable, programmable and useful. At the time it was produced, it was an excellent "tool" to expose qualified students (those with aptitude) to computer technology, including the design, programming and operations of computers.
Although there has been no indication that the following assumption would be true, I am sure if it had been successfully marketed, John Blankenbaker would have eventually sold attachments for it and it would have become more user friendly to further enhance its use in classrooms. The attachments I speak of would have been a "Ten Key" pad to enter code, later an "Alpha-Numeric" keyboard and a small "Dot Matrix" printer. I know a lot about CTI Education Products, Inc. I am certain that had the profit potential they hoped for been realized, they would have most certainly made those enhancements to it.
I also made training videos and provided personal instruction to teach salesmen how to demonstrate the Kenbak-1, as well as helping electronics instructors to use it in classroom environments. Unfortunately, the concept was so new that educational salesmen could not convince schools and colleges to implement it for teaching "Computer Concepts" or "Programming". No doubt had the Kenbak-1, been a success, schools and colleges over the United States would have produced "Computer Literate" graduates much earlier than actually happened. In my personal opinion, "Educators" missed an opportunity to provide their students with "computer backgrounds" earlier because of their unwillingness or "mental" inability to work their way through the Kenbak-1.
To my knowledge, Nielsen Electronic Institute was the only Junior College or for that matter the only school, to effectively use the Kenbak-1, as a learning tool for programming or to enhance the understanding of Main Frame computers and the actual visualization of memory, arithmetic, index and instruction registers, during the execution and instruction cycles of programs, by electronic technicians. The latter was because the Kenbak-1, could be "Single Cycled" and by proper use of the console, everything could be visualized by bringing it up on the output lights. It is truly a miraculous machine. Sometimes, I wonder what Bill Gates could have done with it, had he been made aware of its power.
A Kenbak-1, was first placed in the Boston Computer Museum and it has since been transferred to The Computer History Center in California. Another was placed in the First Computer Museum of Nova Scotia. Those two are the only Kenbak-1, computers that I know of on public display. They are extremely rare because only forty (40) were built. Of those built, I now control seven (7). Fortunately for me, when CTI went out of business, I purchased the training manuals, schematics and some pieces and parts. I still have the video tapes (old commercial style) of when I was demonstrating to the CTI salesmen how to program simple counting routines, enter the program, read it back for accuracy, enter the data to be counted, Lock it for safety and finally execute it. The video also demonstrates troubleshooting the program or interrogating the Instruction Registers to determine the next instruction to be executed, or reading the Arithmetic Registers to determine its/their contents. Reading the contents of memory cells was also demonstrated.
Because the Kenbak-1, is "architecturally" sound, I realized that as time passed, it would have historical value. I also knew that the sales of them were extremely limited and surmised that because of teachers and or students using them without the necessary aptitude, many would be discarded. When I decided to close the Junior College in 1999, I pulled them off the storage shelf along with schematics, some training books, and the videos, still in their plastic cases and stored them in my garage in a large "boat box" I purchased for that purpose. Each time I moved, the big box moved with me. They were not well packed and I believe some of the "no bounce" keys got damaged in the moves. In a trial run of all the computers, only one was actually working. Because the console "keys" are the only way to "input" a program, a broken or loose key prevents any further testing. I started to re-attach some of the keys with super glue, but decided that should be done by an expert, possibly in the restoration section of a museum.
In addition to the copy provided to the Boston Computer Museum and the First Computer Museum of Nova Scotia, there may be another copy in circulation. Mr. John Blankenbaker indicated in a telephone call I made to him (year 2000) that his Daughter had reported that she heard that a Kenbak-1, was sold on E-Bay. Notwithstanding those three, other than the seven in my possession, I do not know of any others. If I am correct there would only be ten (10) in existence. When I was talking with John, I asked him if he had any computers, he stated that it might be possible for him to put a copy together from some parts he had stored somewhere, however he indicated that he now had other interests and that his time and investment in the Kenbak-1, was wasted. I personally do not believe he will attempt to put another Kenbak-1, in operation.
I praised the little computer to John. He acknowledged that other "programmers" really liked his invention and expressed an interest in it, just as I had. But he informed me that his computer wasn’t designed for experienced programmers, it was designed to "teach students" how to program. The fact that other programmers liked it didn’t impress him — it appeared he was disappointed that it could not be sold in quantities to educational institutions, to teach people about computers, which was his ultimate goal. I got the distinct impression from him that he himself would have been an excellent educator in "Computer Science". Because so many years had passed when I was conferring with him, he indicated that the computing industry had passed him by with technological advances. His main interest was now in the Genealogy of his ancestors and he was devoting all his time to building a Blankenbaker web site.
In the same telephone call I asked him to: "Please write your Auto Biography as there is definitely a place in history for it". He replied, "Bob, I’m only 70 years old. I’ll do that when I’m too old to work on my other interests". I chuckled at that thought and we soon ended the conversation. Now, I’m 70 and feel just about the same way! Unless John reads this story, he probably does not know how valuable an asset his little computer was to my Junior College and the students that had an opportunity to be trained on it. They would number in the high hundreds, and perhaps in the thousands.
Because CTI went out of business, I felt compelled to purchase all the Kenbak-1, material they had in stock, which was not much. When they closed, everything was stacked in piles for the auctioneer. CTI had already done a major cleanup in the plant. I was fortunate to have a few front plates (console) complete with keys, power supplies and several mother boards. In addition to purchasing the hardware, I also purchased the "schematics" complete with component identification for insertion on the mother board. CTI sold me all of their "copyrighted" material as I was using numerous books on electronics published by them. I have not renewed any copyrighted material, as technology has long since passed it by. It should be in the public domain and anyone wanting to reproduce it would be entitled to do so.
My plans are to find a respectable "home" for the remaining Kenbak-1’s, the complete documentation, consisting of one complete lesson that was used by the college to teach how a simple problem could be handled. That included, the General Flow Chart, the Detail Flow Chart, use of custom made, Symbolic Program Coding Sheets, and Constant Information Coding Sheets. The steps necessary to Manually Convert or "Compile", the Symbolic Program to Numeric Code is explained and demonstrated. An Electronic Technician’s, presentation is demonstrated using a general description of all internal components needed by the execution of the program, with emphasis placed on the electronic connections of the necessary components during the Instruction Cycle and the Execution Cycle with space to record the contents of the Arithmetic Register, Index Register, Instruction Register and changes in Memory for each instruction executed within the program. The Memory Map is presented prior to execution and a separate Memory Map shows memory after execution. The "coding sheet" is broken down for further understanding of conditions of registers and memory for each step in the program. The use of each "training tool" is explained in depth. This one problem, taken from scratch, programmed and executed is demonstrative of the power the Kenbak-1, had as a teaching tool for Electronic Technicians. The Kenbak-1, could not conceal any mysteries for technicians that this special example would not uncover. The use of each "training tool" is explained in depth. Next, is the schematics for the Kenbak-1. They appear to be "used" but complete in all respects. Of course, the video material where I personally demonstrate a simple program and take the Kenbak-1, through its steps, is also available.
My only income is Social Security and I am not in a position to make a gift of the Kenbak-1 and its associated material at this time. Until someone expresses a "genuine interest" in them, and makes me an acceptable offer, I will keep them in my possession. I have been advised by experienced collectors, that if anyone bought the remaining seven, they would probably horde or destroy some of them to drive the market value up. That thought disturbs me greatly and I would have no part of it. I have had museums and collectors all over the world express a desire to own a Kenbak-1. Money always seemed to be their problem in the final analysis. I found a lot of collectors that pay the freight on used computers. I fear that one day, when they die, their garage full of "collectibles" will end up in a dumpster, headed for a land fill.
The only way I can protect the Kenbak-1s, is "sell" them for a substantial price. Anyone heavily invested would be more inclined to protect the treasure they had in their possession. Perhaps some day, I will once again contact foreign organizations and give them another opportunity to purchase one. Computer history, is certainly important and foreign countries need an opportunity to exhibit or demonstrate the historic Kenbak-1, for research projects, and other educational purposes. The Kenbak-1, should play a role in history just as all other technological inventions have. It must be protected!
At the present time I have no inclination to "reproduce" the schematics, however I am not indicating that each owner of a Kenbak-1, should not be entitled to a copy to lay beside the computer, allowing for the exploration of the methodology used by its inventor. The same should be said for the training manual, which describes the architecture, and instruction code as well as the operating principles of the Kenbak-1. A Kenbak-1, without the training manual would be hard to understand. A complete analysis of the mother board, without the schematics would be even more difficult. With the manual, it is self-explanatory to anyone familiar with computers — not necessarily someone considered "computer literate" by today’s standards, as there is no "software" to do the myriad tasks that professional computer software program writers have incorporated into the daily use of PCs today.
John Blankenbaker’s expertise in design is clearly demonstrated in the schematics used to assemble the mother board of the Kenbak-1, and in my opinion they are invaluable. I can hardly imagine, that some day in the future, someone will want to study in depth, the design. Without protective control of the schematics, they could disappear. Researchers and historians would be cheated out of their chance to study the Kenbak-1. One day, the schematics in my possession, with an accompanying Kenbak-1, will probably be considered priceless. It is the Mona Lisa of "personal computers".
It would he nice if the "Computer Museum of Nova Scotia" held a news conference pertaining to their new acquisition of the Kenbak-1. Even better, it would be nice, if this little story could make it into some of the major publications on PCs. If the United Press International (UPI) would publish an interesting article on it, it may quickly gain world wide publicity. Because so few are in existence, I believe there are owners of major computer manufacturing companies that would like to have the historic Kenbak-1, in their possession, but they need to know of its existence. In the past I tried to get the attention of Bill Gates, but to no avail. A well put together news conference with a UPI reporter or a story or two relating to the background presented here, may be sufficient to make such an article newsworthy. Perhaps it will happen! The Kenbak-1, has not yet seen its day of "glory". I hope that happens in my lifetime. It has provided me with so much satisfaction, I can hardly describe it!