Phil’s Past Interests – How Stuff Works
PAST ELECTRONIC INTERESTS:
I have always, even as a child, been interested in how things worked and how they were put together. When I was three years old someone brought me a big red plastic fire truck which actually squirted water through the fire hose. Before the person who had brought the present left, I had the fire truck all taken apart. My dad could not figure out how to get all the pieces back together, and my parents were really angry!
I know that as a kid, the sight of a soda machine taken apart intrigued me. What was inside there? What made it work? I used to find old radios lying in prairies and would examine their insides. I would open up the capacitors and find nothing inside other than something like tin foil. Where was the magic? I would take apart alarm clocks and examine the gears. Whenever I would get something new, I would look forward to the day when I could take it all apart – this drove my parents crazy!
When I grew to be a teenager, my interests became more directed towards electronics. Absorbed in science fiction programs on TV, I attempted to construct a control system that consisted of a master control and auxiliary control. Master control could override auxiliary control, and there was a way for auxiliary control to override master control if you knew how to do it. This all revolved around a canister-type vacuum cleaner on wheels that would roll across our basement floor. My dad thought it sounded like a jet airplane, especially with the system I had invented for gradually increasing the speed of the 660-watt motor. This was great fun when friends came to visit, and I constantly found new ways to re-wire and revise the system. At the time I was around 15 years old and did not have access to a camera or computer to document this. I did, however, have access to a typewriter and hope to update these documents to computer format. When I have this available online, you can click here to see it.
During my later high-school years I began to collect and disassemble broken televisions and radios. I also collected old training manuals concerning TV/radio repair and television broadcast signal standards. In my junior year of high school, I built a 5-tube AM radio receiver. By the time I graduated from high school, I was repairing radios and TVs in my basement workshop. Click on the following pictures to see a larger version:
This basement workshop and the test equipment are now just fond memories of an obsolete era of my life. I thought that I could build a better mousetrap and make my fortune as an inventor. Most of my time was spent repairing radios, TVs, and stereos for relatives, coworkers, etc.
There was one little project I built during this time that was somewhat revolutionary, and represented the height of my achievements in this area. I designed a multi-purpose box that controlled my basement workshop. These are the functions it performed:
- It monitored the phone line and if it detected an incoming call would use a ringing generator to ring “illegal” extension phones. This was back in the 1970’s and I was told that Illinois Bell would measure the ringing current to detect if there were any unauthorized extension phones on the line. My box would monitor the phone line through a 1,000,000 ohm resistor so the current drain was minimal.
- It monitored the lighting in the area using a photocell to determine if someone was there. If the fluorescent lights were on in my workshop and there was a power failure, it would use a battery backup to start an overhead 12-volt fluorescent light so I would not be left in the dark.
- Using another photocell it also monitored the light by the stairway leading down into the basement. If someone stood at the top of the stairs and turned the south basement light on, off, on, and off again it would light the stairs for a predetermined number of seconds to give the person time to get down to the workshop. This was useful because my mother and I would “live” in the workshop area and once you got downstairs there was no way to turn the basement light off since the switch was at the top of the stairs. My mother requested this feature so we could save money on our electric bill.
- If a special button was pushed on the control panel it would light the stairs so someone could go back upstairs.
- There was a hold circuit such that someone on the phone could be put on hold in my bedroom or in the basement workshop and taken off hold in the destination location. There was a hold switch and indicator on the main control panel, and a switch and indicator on a smaller control panel in my bedroom.
This little box also had some special design features:
- All main circuitry was implemented on plug-in circuit cards. These cards could be removed for easy troubleshoot and repair. The most critical circuit board had a spare copy made to act as a backup.
- When the case was closed, all adjustment circuitry was still accessible from the outside of the case through the ventilation holes.
- All interconnections were through double banana plugs on the back of the unit.
There was also an eight-ampere power supply with battery backup that was used to power this and the stereo system in my basement workshop. It had constant and variable-voltage outputs.
UNFORTUNATELY, so much of me went into this project that I could not throw it away when it was no longer being used. Since I still have the pieces of the project and the plans that I used when I created it, I should be able to digitize all this. Maybe then I will be able to destroy these memories of the past and finally let go of that which I can’t admit I have lost.
Here are the plans.
Here is the control panel.
Here is the power supply.
PAST COMPUTER INTERESTS:
When I was in high school and people saw what I was interested in and how my mind worked, they said I should be a computer programmer. I did not see that as the real challenge. I thought that I would design and build computers, and instead pursued a career in electronics. Besides, computers in the 1970’s were programmed through key punch machines and Hollerith cards – hardly fun!
My first memory of being really interested in having my own computer was in the late 1970’s. People were starting to build home computers, and I remember playing with a Teletype machine at work and storing messages on paper tape. Click here to see an example of a Teletype paper tape message from that period in my life.
As my career in electronics progressed, I realized that although I could build things using my skills, the real magic was in the programming that made it work. I always thought that I would build my first computer, and spent countless hours studying microprocessor data sheets, memory chip timing diagrams, and looking briefly at assembly language and compilers. Eventually, I decided it would be better to buy a computer and see if I enjoyed working with it before committing to a huge project.
My first computer was a Commodore VIC-20 that I bought for $80 at K-mart in the early 1980’s. At first, I didn’t have the cassette backup unit, and had to manually type BASIC programs into the machine every time I wanted to run them. My parents bought me the cassette unit for my birthday. The machine came with 4KB of memory built-in. At a later date I bought the 16KB memory add-on for $100. With 20K of RAM, I thought I was set! When I bought the VIC-20 I already owned a Teletype machine. I constructed an RS-232 to 20ma current loop interface using opto-isolators so I could use the Teletype as a printer. Eventually, I purchased a used Heathkit dot matrix printer to use with the VIC-20.
My next computer – and my first “real” computer – was a Kaypro II. It ran the CPM operating system which was a standard at the time. It had 64K of RAM (how could I ever need more?), two 200K floppy drives, a built-in monitor and keyboard, a printer port and a serial port. I remember being at the computer store where I had bought it – the salesman thought it was so complicated, and wanted to tell me how to use it. I had already looked at the manuals, and thought it was a cinch. I interrupted his talk about how to use the machine and said “What I need to know is how to input saved programs on paper tape from a Teletype machine into the Kaypro.” He stopped, gave me a totally blank look, and told me he had no idea what I was talking about. He realized that I was way ahead of his little tutorial. I later discovered that I could give the Kaypro a command to switch the system console out to the Teletype which allowed me to feed the paper tape into the Teletype after using the keyboard to enter the BASIC program – the Kaypro just thought it was the world’s fastest BASIC programmer. This was how I transferred all my Commodore VIC-20 BASIC programs into the Kaypro.
I used the Kaypro for quite a number of years, and I have fond memories of all that it taught me concerning telecommunications, programming, word processing, spreadsheets, etc. Eventually, as I neared the end of the 1980’s, I realized that the world was being taken over by the IBM PC. For years I admired them from afar, but they were way out of my reach financially. When I bought the Kaypro, all the hardware and all the software was $1500. Buying the IBM with the hardware only was $3500!! Around 1988 I managed to buy a used IBM PC (not an XT).
One of my first challenges was to get my programs working on this new operating system. After all, this was not CPM, it was PC-DOS. For instance, I had a program that I had written in COBOL. When I converted to the IBM PC, I wanted to make it work in some language that was easy to use on that machine. As I recall, I re-wrote the program in BASIC and when I could not get it to work, re-wrote it yet again in Pascal. The Pascal version worked fine. Another example of a program that I used extensively was one I created to allow me to change, test, and reset printer parameters on my Epson RX-100. I never really finished the program as I originally designed it, but the functionality it provided was very useful.
I immediately sank hundreds of dollars into the IBM PC to buy extra memory and interface cards. By constantly updating this machine I learned a great deal about computer hardware, although it was a very expensive lesson. Eventually I had replaced everything in the machine except for the motherboard. I could not afford a new computer, so someone convinced me that replacing the motherboard was not a big deal. In 1990 I bought a book to guide me through the intricacies of the process and bought an 80386SX 20MHz motherboard for $300. At that point, I had replaced everything in the case and was able to build a computer from scratch. Over the next few years I continued learning more and building computers, eventually becoming a network administrator at Motorola in 1992.