The Binford Monitor

May 1996

A computer is of little use unless it can somehow interact with you. (Note that it really does not need You to talk to It!) We are all familiar with the Personal Computer paradigm of a keyboard and a monitor. But even a computer buried in the bowels of an automobile has some means by which it can communicate to a human. It may be through the car's radio display, or you may need a big honking diagnostic center, or maybe you have to connect a logic analyzer to its pinouts, but sooner or later, every computer that I am aware of provides some means of displaying information to its human.

When I first started using computers, CRTs were available only in the most esoteric of research labs and NASA and places like that. We used the good solid industrial strength ASR 35 Teletype, which ran at a full 10 characters a second (CPS). Sometimes we reverted to an ASR 33, which was the cheaper plastic version of the ASR 35. Once I even had to deal with a Badot Teletype, which was slower yet, and which used an internal coding structure that was only six bits long, not the seven bits that ASCII has, or the eight bits that the PC implements internally.

Over time we got a few 15 CPS Selectric terminals, with the golf balls. They were quite reliable for a 3 CPS secretary to type on, but failed miserably when a computer would try to use the full bandwidth of the device. Then 30 CPS terminals showed up, generally with pin printing heads, rather like the really cheap personal computer printers we still find available today.

A salesman walked into my office one day in the early 70's from, of all places, the Corning Glass company. They had developed a CRT terminal for office use, and they were trying to sell these things for a lease rate of about $200/month, in 1970 dollars. After we got up off the floor laughing (my mortgage was only about $250/month in those years), we asked him how we were supposed to get printout off this thing. He said, oh yeah, you still need one of those other printer terminals too. Printout was essential in those days, because nobody had yet developed a full screen editor, not even a crummy one like 'vi', at that time. We threw the guy out the door, and the Pirex trademark never did become a household name in the computer business.

A few years later, near the middle of the 70's, CRT terminals had finally come to be affordable. There were a whole raft of companies selling these things, most of whom are now out of business, like ADDS, and ADM, and the still hanging in there DEC. These things could crank all the way up to 1000 characters a second, and a few even to 2000 cps. They were still black and white (or green and white). I saw my first color terminal in 1981, and it cost near $10K then.

They all spoke ASCII, but the commands used to control the enhancements, like reverse video, blinking, and cursor movement, were all incompatible. In the early 80's an attempt was made to come up with a compatible protocol for these terminals, and after a lot of yelling and hollering, an ANSI standard was established, essentially based on the DEC VT100 terminal. Thus, anybody that today uses their PCs to dial up a bulletin board or a character based Internet service provider, needs a package called a Terminal Emulator. Procomm is one such. The Windows program named Terminal, or the Win95 program named HyperTerminal, are others. All terminal emulators give you some selection of terminal protocol, which defines the enhancement codes used by all these old CRTs, and just about everybody defaults to the VT100 code, which was essentially the ANSI standard. Over the years, even DEC enhanced things (VT200, VT300 and so on) to the point where we still have a babble of incompatible terminal protocols. That was the nice thing about Microsoft's DOS -- when it came out, they laid down the law, and pretty much everybody writing a DOS or Windows program adhered to that standard.

The PC originally came out with two monitor types, the Monochrome high resolution monitor, and the incompatible CGA monitor, which had four colors only, and crummy resolution. People doing number crunching generally bought the Monochrome one (because it had a good graphics mode), and most home people bought the CGA one (because it was cheap). At World Wide Widgets in about 1983, a year after the PC was introduced, we did implement an industrial process control display using the CGA monitor, where it showed a dynamically changing bar chart of the thickness of the Widgets being produced, and the intensity of some spray nozzles spraying cooling fluid onto the widget making machinery. We were able to present all the information in a compact form using different colors, although the graphs were quite grainy by today's standards, and the four colors available were a pretty icky selection. My recollection is that it was shades of purple and blue.

A couple of years later, IBM introduced first the short lived EGA display, then the still existing VGA display. The reason the VGA display has survived this long is, I believe, that unlike the previous two color displays (the CGA and EGA), the video input to the VGA monitor is an analog signal, whereas the other two were digital. Thus, the EGA display was forever limited to 16 colors, because there were four input signals, and the signals were discrete (on or off). The VGA has only three input signals, but those signals are analog, allowing the monitor, with an appropriate computer adaptor card, to generate the full (24 bit) 16.7 million colors that people consider a full color monitor requires to display real looking images. (Most adaptor cards do not put out the 24 bit signals, but are limited to 8 bit (256 colors) or 16 bit (32768 colors), but this is a problem with the adaptor card, and not the monitor design).

In the past few years, monitors have become capable of higher resolution. VGA is 640 X 480, which means that it will display pixels at 640 positions across the screen, and 480 lines down the screen. This is actually far better than your TV set, but they use different philosophies in how they display their images. TV sets are not digital, and do not really restrict themselves to concepts of pixels, whereas to display a 7 point character on a monitor clearly, you really do need very reproducible places where to turn your light beams on, and so need to pixelize the image. Monitor resolution capabilities have grown to the alleged super VGA of 800 X 600, and the more standard workstation resolutions 1024 X 780 (which is what I personally use at home and in the office), and 1280 X 1024. We are starting to see some 2048 X 1600 monitors too.

The problem with such resolutions, is you need a lot of real estate on your monitor to display the image in a size big enough to see the characters. That is why I use 1024 X 780. At home, I have a 17" monitor, and at work a 20" monitor, both capable of higher resolutions, but my eyeballs are not equipped to read the resulting text even on the 20" monitor. And monitor price seems to go up exponentially with size. A 15" monitor seems to run about $300, a 17" about $600, a 20" about $1500, and you can quite quickly get into the multi thousands of bucks by going larger from there.

And these things are heavy. My office monitor weighs about 60 lbs, and takes a large animal and a strong boy to schlep it around. We have had the need to make computer presentations to small and large groups of people, and it gets quite old real quick to have to unplug your system, wheel it into a conference room, and set it up, and still have the guys in the back of the room griping about how they can't see any of the details.

When I first arrived at my current assignment within the WWW organization in 1989, we found the need for frequent group presentations because we were finally getting PC technology down to the engineer's desk, after they had been allowed only on manger desks for the previous several years, and we had a lot of training to do. About this time little devices became available which were liquid crystal displays that sat on top of a conference room overhead projector, which would project a black and white image of what was on your computer monitor onto a projection screen. The little device plugged into your monitor port on your computer and took the place of your monitor, although it itself had a plug to let your monitor plug into it, so you could still have both available. These things did have a simulation of colors, in that they had allegedly 16 levels of grey scale, although I could never discern more than about four, and for all that, they cost about $2000. The early ones had the problem that after about a half hour on the overhead projector, the liquid crystal display started to fade out for some reason and you had to let everything cool down. This problem eventually got corrected.

A couple of years later, color displays came out, for a price around $4000. Their problem was that you just about needed a searchlight under it to see any kind of image on the screen, because the internal technology was so opaque. To some extent, this is still the case, and the the vendors of these devices still recommend a really strong overhead projector bulb for adequate presentation.

At the Spokane Computer and Business Show held here last October, there were a couple of companies that were displaying a new advancement in this technology, where everything is self contained. You can get this little black box, which contains a very high intensity bulb, and a liquid crystal screen all in one package, along with a zoomable focusing projection lens. This device also connects to the VGA port of your computer, and some of them even will connect to soundblaster ports and produce not only a video image, but any audio sound that your program would generate. These things weigh about 15 lbs, have a carrying handle, and can be bought with an optional shipping case. They will display very clear and crisp images as large as 10 by 8 feet or larger, in full color, at whatever resolution you want to pay for. The zoom lens helps to size the image to the screen you have available. Some of them have the added feature in that they will connect to a TV signal or VCR output, so you can use these things for your superbowl parties or other video presentations. They allow simultaneous connections to both the computer, and the TV, and allow you to switch back and forth. Although of no interest to most business users, they also connect to Macintosh computers.

The downside is the price. While you can now get the color panels that sit on top of an overhead projector from $3000 - $8000, depending on features, these self contained units seem to start at about $6000 and quickly ramp up to the $12000 level. There are differences in light output and resolution, but most of them handle a true VGA signal with all the colors, and a few will do superVGA. For the real Binford Toolman type people, the people who have 300 hp lawnmowers and jet propelled chain saws, for only $57,495 (plus tax, lenses and VCR input extra) you can get a Light Valve Projector, 1280 X 1024 resolution, 2500 Lumens (the desktop models referred to above are about 150 lumens) for those extra large screens or "high ambient light areas", like on the beach at high noon in Hawaii when you are having your next annual meeting.

For a catalog of about 50 such devices, you can write Minnesota Western, 2633 Eastlake Ave. East, suite 207, Seattle, Wa 98102, and ask for their Computer/Video Projection catalog. This company was one of several that was displaying at the C&B Show, and seems to have the most complete catalog that I have seen. I have reason to believe that the prices listed in these catalogs seem to be heavily negotiable. A local company that I am aware of that sells such units is Modern Office Equipment. I do not know if they have a catalog. And, as always, you should start your search by leafing through the ads found in your local ComputorLink Magazine.