The Kenbak-1 - The World's First Personal Computer
The Kenbak-1 was created in 1971 by John V. Blankenbaker and recognized in 1986 as the world’s first “Personal Computer” by the Boston Computer Museum. This computer was designed before microprocessors were invented and consisted of small and medium scale integrated circuits mounted on one printed circuit board. I personally employed these computers at Nielsen Electronics College 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 “microprocessor” technology that was gaining momentum.
More information on the history of this amazing computer can be found online at the following resources:
This is my first hand, personal account of the Kenbak-1. A lot of people have displayed renewed interests in the first personal computers, but few can say they extensively taught and used them.
- 1 KENBAK-1
- 1.1 The Kenbak-1 - The World's First Personal Computer
- 1.2 FIRST EXPOSURE TO KENBAK-1 – WORLD’S FIRST PERSONAL COMPUTER (PC)
- 1.3 KENBAK–1 - EMULATES “MACRO” PROGRAMMING INSTRUCTIONS
- 1.4 KENBAK-1 – MARKETING OBSTACLES PRESENTED TO CTI
- 1.5 KENBAK-1 – DESIGNED MANUAL “COMPILER”
- 1.6 KENBAK-1 – ADVICE NOT HEEDED – HIGH SCHOOLS TO BE MAIN MARKET
- 1.7 KENBAK-1 – APTITUDE TO UNDERSTAND PROGRAMING IT BECOMES MAJOR PROBLEM
- 1.8 KENBAK-1 – IMPORTANT TRAINING TOOL IN ELECTRONICS TECHNOLOGY
- 1.9 KENBAK-1 – SIMULATES “MSI” MICROPROCESSORS
- 1.10 KENBAK-1 – I DEVELOPED VIDEO TRAINING TAPES – USED TO TRAIN INSTRUCTORS
- 1.11 KENBAK-1 – CTI RENAMED IT, COMPUTER SYSTEMS TRAINER - 5050
- 1.12 KENBAK-1 – ENTERED INVENTORY AT SCHOOL IN 1973
- 1.13 ALL KENBAK-1 MATERIAL ARRIVES AT CTI – WHAT I OBSERVED AT THAT TIME
- 1.14 KENBAK-1 – INVENTOR RELATES THAT HE BUILT HIS OWN COMPUTERS
- 1.15 KENBAK-1 – CTI GEARING UP FOR MASS PRODUCTION
- 1.16 NEITHER CTI NOR THE INVENTOR REALIZED THEY HAD FIRST PERSONAL COMPUTER
- 1.17 KENBAK-1 – VERY LIMITED SALES – ONLY 40 SOLD
- 1.18 MY SCHOOL – FIRST AND ONLY USE OF THE KENBAK-1
- 1.19 MODIFICATIONS TO THE KENBAK-1, THAT COULD HAVE BEEN
- 1.20 JOHN V. BLANKENBAKER – SHORT DISCUSSION ABOUT KENBAK-1
- 1.21 HISTORICAL VALUE OF THE KENBAK-1 – REALIZED VERY EARLY
- 1.22 KENBAK-1 – FIRST PLACED IN THE BOSTON COMPUTER MUSEUM
- 1.23 KENBAK –1, SCHEMATICS, MANUALS, AND VIDEO DISC, PLACED IN MUSEUM
- 1.24 KENBAK-1 – A COMPUTER PURPORTEDLY SOLD FROM EBAY FOR $20,000 DOLLARS
- 1.25 INVENTOR DISAPPOINTED – KENBAK-1 NOT USED TO TRAIN ENTRY PROGRAMMERS
FIRST EXPOSURE TO KENBAK-1 – WORLD’S FIRST PERSONAL COMPUTER (PC)
As best I can recall, it was somewhere around October or November of 1973, when I was contacted by CTI to inspect and advise them on a computer product they were considering. When I first saw the Kenbak-1, it made me very curious. It was a small blue box and it had a console. The console had push button keys, lights and a few switches. Unlike the other digital devices I encountered, there were no wires, other than the power cord. CTI explained that it was a “computer” and asked me if I would evaluate it for use in schools as a device to introduce students to computers and their internal programming requirements. I agreed and personally picked up the computer and training manual. In about a week, I was putting the small desktop sized computer through its paces. I was astonished at the “power” it contained!
Until the arrival of the Kenbak-1, all other devices I investigated for CTI could 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 small Arithmetic Registers could be assembled and tested. Lights on the console would confirm properly assembled circuits, or in some cases, voltmeters would give a (+) or (-) reading. As I recall, building the Central Processor Unit (CPU) was out of the question at the time. That particular kind of training allowed technicians to understand the components and electrical “sine waves” they would encounter in already manufactured “digital systems” but the technology could never emulate a completely assembled system.
Our “Digital Electronics Course” followed the normal instruction of the era and used stand-alone circuits. For familiarity, students would be taught Boolean Theorems, build “gates,” Half adders, Full adders and other simple digital circuits such as “seven segment” led numbering systems. Having a “lab” that could integrate those circuits into a complete system was out of the question until I examined the Kenbak-1 computer.
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 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.” A counting routing is important, because it can be used to stop counting after a specific time lapse and generate an impulse that could cause some industrial function to become active. A simple example would be controlling “traffic lights.”
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 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.
As I recall, I entered a number in memory, matched it and “branched/jumped” from the main routine into a subroutine to automatically stop the computer. Using the Console, I could verify the match visually. I also discovered I could modify or trouble shoot the program with ease because of its design. The Console permitted me to enter an Address in memory and display its contents visually on the Console lights. That included all the registers including the “Program Control Register.”
The computer allowed the programmer to predict the next instruction to be executed and it had a “Single Cycle” feature that sometimes was essential in troubleshooting programs. Of course, programmers would seldom be allowed to use that feature on Main Frame computers, however, Service Technicians frequently needed it. In my opinion, it would be a tremendous help to beginning programmers. I imagined later, as they gained experience, they would be using Print Outs of their complete programs with all kinds of computer-generated comments on improper Instruction Code to facilitate troubleshooting. When that happened, they would think they were in heaven compared to having to do it all through the console of the Kenbak-1. Making that change would be delightful and from the onset, they would know what the Print Out was, and how it was intended to be used.
The little computer‟s power was explored in depth and I became satisfied it had “programmable power.” Although the accompanying manual described many programs and provided 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 needed in the “housekeeping” steps. Because of me, the Kenbak-1, now had its first “Compiler.”
After coding, the programmer only needed to insert the actual code on the same line with the symbolic code. As any programmer knows, the use of Symbolic Programming prevents having to memorize the Mnemonic equivalent while working out the actual program. On the Kenbak-1, it meant a lot more. All the Mnemonic Instructions had to be further reduced to the “Absolute” Binary Code, prior to entering it into the computer. In other words, the computer was only programmable by inserting absolute Binary. All outputs were also in absolute. In my mind, the programmer could readily grasp the reason to submit the Symbolically Coded program to Card Punch Operators in preparation for having the computer do the compiling automatically and print, or punch out the complied program, ready to be corrected, processed against “test data” and “debugged.”
As I visualized it, the programmer‟s main concentration in learning the Main Frame computer would need to be on the “peripherals” attached to the computer and of course the Manufacturer‟s recommended Instruction Set. I also believed their Instruction Set would be easier to master, because the neophyte trained on the Kenbak-1, would have been introduced to many of them earlier. They would easily grasp the concepts of “dedicated memory buffers,” attachments such as a Printers, Automatic Card Punch Machines and Magnetic Tapes or Disc Drives as output devices. They would have experience with a Binary Output on the console of the Kenbak-1 that would reinforce learning the manufacturer‟s console. I‟m not indicating Binary Coded Decimal or Hexadecimal would not need to be further refined in the programmer‟s mind, only that it should be grasped more easily because of having exposure to Pure Binary or Octal on the Kenbak-1. When properly used, the “Hexadecimal” concept could also be demonstrated on the little computer.
KENBAK–1 - EMULATES “MACRO” PROGRAMMING INSTRUCTIONS
Computer Manufacturers pride themselves on powerful instruction codes. To add power, they produced “Marco” instructions. These instructions were not normally “hard-wired” into the computer. They were included in the instruction set, but the Compiler program recognized them and produced a series of program instruction codes in the form of a small “Routine” that was added in every detail to the program being written. These small subroutines could allow for leaving the Main Routine, “memorize” the point it left, “Branch or Jump” to another routine, fully execute the Sub-Routine and automatically “return” to the place in the Main Routine it had left. Instructions of that nature prevented a need for “detailed” coding by a programmer. Macro‟s were designed by software programmers and were “pre-programmed” and usually a coding format meeting certain specifications were required. The little Kenbak-1 could simulate on a small scale how a Macro could do such functions!
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 they truly had a small copy of
I was so impressed with the Kenbak-1 that I promised
KENBAK-1 – MARKETING OBSTACLES PRESENTED TO CTI
Because I wanted to assist
I acknowledged current text materials covered all of that, but it was theoretical and highly abstract in nature. I explained that the instructor teaching those things had to be highly qualified to be effective with a medium-sized class. By using the Kenbak-1, students would have the advantage of getting accustomed to the internal workings and procedures for programming a computer and avoid mistakes later on, as they began running their test programs on “full-blown” computers. Students with the proper “aptitude” would have little or no difficulty-absorbing computer programming concepts on the Kenbak-1.
KENBAK-1 – DESIGNED MANUAL “COMPILER”
Additionally, if CTI would follow my advice, I would provide them with a “Symbolic Coding Sheet, whereby the Kenbak-1, Instruction Set, could be manually coded against a flow chart and easily converted using manual techniques to Machine Code. That simple step would explain to students in a very personal way how the Software of a full-blown computer, could automatically take their coded program and make the conversion into Machine Readable Code for them. In other
The work they would be doing on the Kenbak-1, could be related to any Main Frame computer on the market. Knowing the “Console” on the Kenbak-1, would greatly assist them when they encountered the “real thing.” In short, I envisioned the early programmer, “Flow Charting,” “Coding,” “Compiling,” entering and running several simple programs on the Kenbak-1, prior to taking up and wasting “valuable” time on the actual “Main Frame Computer” in their school or college.
KENBAK-1 – ADVICE NOT HEEDED – HIGH SCHOOLS TO BE MAIN MARKET
Unfortunately, CTI had their ideas on marketing the Kenbak-1. They wanted to concentrate on “High Schools” and use them as a market. Personally, I thought that would be a mistake. In my opinion, the High School teachers lacked the professional knowledge needed to teach the Kenbak-1. I reminded them that my experience with students coming into the Electronics Program from such schools
I also explained that High Schools, had few “Out Come Evaluations” placed on the teachers of those courses and students were allowed to “skate by” many of the theoretical evaluations within the course. I warned CTI that based on
I warned CTI that based on
It took time to schedule the sales staff, as
I learned at the initial presentation with the
KENBAK-1 – APTITUDE TO UNDERSTAND PROGRAMING IT BECOMES MAJOR PROBLEM
The Kenbak-1, was a small portable “Main Frame” and to fully comprehend it, one required the same programming aptitude needed by professional programmers. Because of my experience with hundreds of Computer Science Students, I assumed some salesmen and schoolteachers would be unable to grasp the necessary concepts. I was correct in that 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. Some of them were sold prior to CTI‟s involvement through magazine advertisements. Of the forty sold, I purchased eight from CTI.
KENBAK-1 – IMPORTANT TRAINING TOOL IN ELECTRONICS TECHNOLOGY
My Kenbak-1, computers were not used to teach Computer Science. The college had NCR and IBM, Main Frame computers to accomplish that. The
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
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 Blankenbaker designed the “motherboard” with the chips separated from each other as far as possible, keeping with the small “
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
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 the cars and determine the length of time to hold a light green, then “time” the caution light, turn it off, switch on and hold the red light “on” for a predetermined period of time and later return to the beginning only to repeat the process. Similar procedures were employed in factories to control industrial functions. Problems like this one were a natural for the Kenbak-1.
KENBAK-1 – SIMULATES “MSI” MICROPROCESSORS
Understanding an “Output” and the variables under which a computer could provide one was required by
If one takes the time to analyze the power John Blankenbaker designed into his Kenbak-1, they would be truly amazed to learn he incorporated a complete computer with everything needed to process data, except speed, a larger memory, output signals to drive printers or otherwise record data on magnetic tape or discs. His output was by “lighted outputs” on the Console, which
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. That step is referred to as “housekeeping.” One had only to release the “lock” to perform that function. Once the program is entered, the
KENBAK-1 – I DEVELOPED VIDEO TRAINING TAPES – USED TO TRAIN INSTRUCTORS
I also knew 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. In order to facilitate the task of teaching the instructors, I set out to make the same demonstration for them I made for CTI and record it on
The rehearsal indicated he would need to keep the camera on the computer and my hands. At other times I would need to refer to written material and he was to focus on that and follow my “pointer.” Because of that
The VHS was converted to DVD and the disc shown below has a “dim” but understandable presentation of the Kenbak-1, which takes 3 hours to view in its entirety. Scenes of Nielsen actually manipulating the computer console push buttons and visuals of the corresponding lights show up extremely well.
Digital Instructors would have a personal session with the Kenbak-1 and me and then be allowed to watch the video presentation. After that, they would have an opportunity to ask questions again. Eventually, they were required to solve the exact identical problem without the benefit of the video presentation or help from me. Once they passed that step of their training, they had to prove to me they could troubleshoot the computer. That entailed having to read the contents of memory locations to me, predict the next instruction to be executed, display the arithmetic register, change “constants” to lengthen the “loop” time and otherwise demonstrate they had a full understanding of what needed to be taught to students at a minimum.
Some instructors had never worked in an industrial environment and had to be shown how the Kenbak-1 could be used to simulate Microprocessors. I normally accomplished that by “talking” them through simple industrial functions and explaining how the small voltage from activated sensors provided “input” to the micro and after processing the input against other variables, it could produce an “output.” Hypothetically, the output would engage electronic circuits or relays outside of the computer to perform specialized industrial tasks. I also asked them to emphasize that some micros could take more than one input and through programming, make tests of the inputs and make more complicated decisions for various industrial processes. The use of outputs would be basically the same. Further, they must explain to students the “output” of one micro, could easily be the “input” to another and further “processing” would be required to perform or not to perform a certain industrial function.
KENBAK-1 – CTI RENAMED IT, COMPUTER SYSTEMS TRAINER - 5050
Appendix I consists of the written material used by students to perform the minimum course requirements in the Electronics Technology Course, using the Kenbak-1 (
The “sleeve” of this publication contains a DVD that was copied from the very old training tapes to train the Nielsen Electronics Institute instructors. It will also parallel the printed material used by students. I gave the original old training videotapes to be displayed alongside the Kenbak-1, computers I sold to The First Computer Museum of Nova Scotia. I also provided them with the DVD and suggested they set up a TV and use a “push and play” system so visitors could see the Kenbak-1 in action.
KENBAK-1 – ENTERED INVENTORY AT SCHOOL IN 1973
In order to establish when I purchased my first Kenbak –1, I used the Inventory Records published by the school CPA. Those records indicate it went into inventory and began to depreciate in 1973.
ALL KENBAK-1 MATERIAL ARRIVES AT CTI – WHAT I OBSERVED AT THAT TIME
I had an excellent working relationship with CTI. When they got their shipment of Kenbak-1, materials in, (1973) there were about eight or ten fully assembled Kenbak –1 computers, several PC cards (the term mother board was not coined at the 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 John V. Blankenbaker sold out to CTI and that included everything, “lock stock and barrel.” In any event, CTI gained control of it. After CTI closed its doors, I had control and owned the copyrighted material.
KENBAK-1 – INVENTOR RELATES THAT HE BUILT HIS OWN COMPUTERS
I feel very strongly that because some of the Kenbak-1 computers were fully assembled, John V. Blankenbaker, its inventor, personally put them together. If such is the case, I consider them invaluable. In September 2003, I sold seven (7) Kenbak-1 computers to The First Computer Museum of Nova Scotia and retained one for myself. I firmly believe all Kenbak-1 computers in existence were built by John Blankenbaker or his helpers. I‟m absolutely certain CTI never built a Kenbak-1, computer from scratch. I also do not believe they sold any, other than to me.
KENBAK-1 – CTI GEARING UP FOR MASS PRODUCTION
I was present when
Because the electronics field was advancing very rapidly, the older, Philco Ford training devices were fast becoming obsolete. Heathkit was entering the training market with professional “breadboard” trainers, completely supported with student manuals. They offered, Direct Current, Alternating Current, Semi-Conductor laboratories and manuals. The labs would support Basic, Advanced, and Digital circuits. It became obvious to me that without an infusion of more advanced electronic training equipment, 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 the capable instructors, and me, whom I taught its “power” to. We had a job to train Electronic Technicians about computers, and we did, oblivious to the fact we were also using the world‟s first personal computer to do it! Amazingly, it served its purpose into the mid 1990‟s.
NEITHER CTI NOR THE INVENTOR REALIZED THEY HAD FIRST PERSONAL COMPUTER
The report indicated that over 320 entries were received. A panel of judges using previously prescribed criteria analyzed each entry to determine if it 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‟m 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.” Nielsen Electronics Institute had already been using the little computer for about 13 years when that announcement was made!
Very little was published in that report about the Kenbak-1, and John V. Blankenbaker has been serenely silent about his accomplishments. I hope the material presented here will further enhance his status and his remarkable invention. I am honored to have spoken and written to him about the Kenbak-1. The information he provided to me is considered invaluable and hopefully, one day, he will amplify more on his background.
I‟ve tried hard to provide a comprehensive history of the Kenbak-1, when it was actually used by students, in a highly productive way as they earned the Associates Degree in Electronics Technology at Nielsen Electronics Institute. Its use in my school is the only known instance where the Kenbak-1 was integrated into a technological curriculum offered commercially to train students in a school or college. Because its design matched the conventional design, of mainframe computers as well as Micro Processors, the Kenbak-1 was kept in constant
“I pioneered the use of the world‟s first personal computer and placed the first microprocessor “styled” emulator in the hands of electronics technicians.”
In other words, I pioneered the use of a microprocessor into an electronics training program.
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 V. 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 to Medium Scale Integration – the microprocessor as we know it today had not yet fully “bloomed.”
KENBAK-1 – VERY LIMITED SALES – ONLY 40 SOLD
Without the advantage of using a microprocessor chip, John V. Blankenbaker 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. Between The Kenbak Corporation and
MY SCHOOL – FIRST AND ONLY USE OF 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 and use of “solid state” 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, the contents of every instruction, memory cell or register could be visualized by bringing it up, either from Registers or Memory on the output lights. It‟s truly a miraculous machine. Sometimes, I wonder what Bill Gates could have done with it, had he been made aware of its power.
MODIFICATIONS TO THE KENBAK-1, THAT COULD HAVE BEEN
Although there has been no indication the following assumption would be true, I‟m sure if the Kenbak-1, had been successfully marketed, John V. Blankenbaker would have eventually sold attachments for it and it would have become more
JOHN V. BLANKENBAKER – SHORT DISCUSSION ABOUT KENBAK-1
I‟ve been in contact with the inventor by telephone and Email. When I asked John if I was correct and 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 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 he still had a set of the original schematics. The PC board was magnificent in its design and John shared the fact it was also his design. Everything inside the cabinet was a perfect fit. There was space above and below the PC motherboard to allow air to circulate for cooling. The power supply was attached to the back panel and a fan, also attached to it assured the components were kept cool. Its Console was the front panel. The design was amazing. Only a small amount of space was required for students to use the Kenbak-1, and refer to the training manual at the same time.
Unfortunately, the concept was so new educational salesmen could not convince schools and colleges to implement it for teaching “Computer Concepts” or “Programming.” There is no doubt in my mind, 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 excellent opportunity to provide their students with “computer backgrounds” earlier because of their unwillingness or “mental” inability to work their way through the Kenbak-1. IBM used signs and they had a simple logo that appeared everywhere. It was only one word, “THINK.” I miss those signs even today and wish they would reappear!
HISTORICAL VALUE OF THE KENBAK-1 – REALIZED VERY EARLY
Because the Kenbak-1, is “architecturally” sound, I realized as time passed, it would have historical value. I also knew the sales of them were extremely limited and surmised because of teachers and or students using them without the necessary aptitude, many would be discarded. When I removed them from our curriculum, I also exercised my option and transferred them from the school to myself personally. 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” specifically 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.
KENBAK-1 – FIRST PLACED IN THE BOSTON COMPUTER MUSEUM
A Kenbak-1, was first placed in the Boston Computer Museum and it has since been transferred to The Computer History Center in California. I sold seven of my Kenbak-1‟s to The First Computer Museum of Nova Scotia. Some were in working order, others were not. Those nine Kenbak-1, computers are the only ones I know of on public display. They are extremely rare because only forty (40) were built. Of those built, I now control only one. Fortunately for me, when CTI went out of business, I purchased the training manuals, schematics and some pieces and parts. I also bought the right to all of their copyrights.
KENBAK –1, SCHEMATICS, MANUALS, AND VIDEO DISC, PLACED IN MUSEUM
I gave The First Computer Museum of Nova Scotia the original schematics of the Kenbak-1 to put on display in the museum. I kept a copy for my own use and consider it my personal property. I also provided the original “Electronic Technician” training materials, used to demonstrate most of the programming functions I‟ve described earlier for them to put on display. I kept the copies and also consider them to be my personal property. In both cases, the copies were more presentable than the originals because of their aging. I also gave them one of the earliest “Digital Trainers” made by Philco Ford. That is truly a treasure. There were two “video cases” containing materials I videotaped for the CTI Salesmen. I instructed the owner of the museum to have them opened, cleaned, copied and copies returned to me. The originals in the case could be put on display in the museum if he desired. As yet I have not received my copies. I had the original videotape I used to train my instructors, taken apart and recopied. The original was given to the museum for the purpose of putting it on display also. The Digital Video Disc (DVD) I made from my original videotape was provided to the museum and it‟s allowed to be “played” within the museum. I still consider all printed and video material to be my personal intellectual property. Much of it will be incorporated in this autobiography.
KENBAK-1 – A COMPUTER PURPORTEDLY SOLD FROM EBAY FOR $20,000 DOLLARS
In addition to the copies contained in the Boston Computer Museum and the First Computer Museum of Nova Scotia, there may be three copies in circulation. Mr. John Blankenbaker indicated in a telephone call I made to him (year 2000) that his Daughter had reported she heard a Kenbak-1, was sold on E-Bay for $3,000. There have been other sales reported to me. In one case a Kenbak-1 was sold for $2,000. In talking with the seller, it appeared he didn‟t know its worth and when he got a $2,000 offer he accepted it. Later I was told one sold on Ebay for $20,000 but I could not get confirmation of that sale. Notwithstanding those already mentioned, other than the one in my possession, I don‟t know of any others. When I was talking with John, I asked him if he had any computers, he stated it might be possible for him to put a copy together from some parts he had stored somewhere, however he indicated he now had other interests and his time and investment in the Kenbak-1, was wasted. In later years he contacted me asking for a “console” light. He built a complete computer for his son except for one of the Console Lights. I‟m sure he found one and completed it. If I‟m correct there would only be a little over a dozen in existence.
INVENTOR DISAPPOINTED – KENBAK-1 NOT USED TO TRAIN ENTRY PROGRAMMERS
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 his computer
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 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