Someone bought unknown ultra rare SpectraView 1 cartridge for $536!
But he didn't make it to work so seller gave him a refund and SpectraView 1 is relisted now:
I investigate this cartridge producer.
I found that Canadian company Compu-Cable Systems still exists but is renamed to Display Systems International, Inc. (DSI).
So I sent email with kindly questions about their Atari products. And I received an answer from DSI president and Spectraview designer - Dale Lemke!
He told me that all DSI Atari documentation and stuff (cartridges, prototypes, PCB, eproms, manuals, source code, etc.) is lost years ago Pity.
But Dale sent me comprehensive info about Spectraview cartridges.
I described this story here (in Polish, sorry):
This is an essence: the original letter from Dale Lemke (with my few comments):
Yes, sorry, very busy. Currently at a trade show in Orlando. I have compiled some of the information that I can remember about the SpectraView products. We do not have any old cartridges left, or any schematics, etc. All we have is what I can remember and have documented below.
Dale Lemke started DEL Compu-Cable Systems in December 1983. The company developed it's first product based on the Atari 800XL, called the SpectraView I. This product was developed for the cable TV industry to be used as a information channel, such as community events, public service announcements and elementary advertising channels. The SpectraView I allowed the user to create "pagesĒ of information with colored backgrounds. These pages could either scroll up, or could be set to change according to preset display times. You could also create a horizontal crawl line that would display at the bottom of the screen. An interface was developed that allowed a Heathkit Weather Station to be connected to the Atari 800XL through the joystick ports. The user could then display local weather information including temperature, humidity, wind speed and wind direction. All information that was entered, could be saved onto a single 5 1/4 inch floppy diskette. That way if the system lost power, it would restart itself, reload all the information and begin to display itís pages of information. The Atari 800XL had excellent composite video output, which made it perfect for the cable TV industry. You could also use a Graphics Tablet with a stylus  to create pictures. Those pictures could be saved on the same 5 1/4 floppy diskette and then those pictures could be scheduled to display between the pages.
The creation of the SpectraView I was no small feat. The program was written entirely in 6502 machine language assembly code. The source code was stored entirely on twelve 5 1/4 inch floppy diskettes. When changes were made to modules, all effected modules had to be recompiled and then all the object code had to be loaded into memory. That memory then had to be burned onto EPROMS. The entire program was 22K in size, but had to be made to fit into an 8K cartridge space. A bank switching cartridge was developed. This cartridge had four 4K spaces on it (two 8K EPROMS). One 4K space was always resident in memory, and the other three 4K spaces could be switched in or out, one at a time . This got 16K of the program into the Atari, but 6K still needed to be dealt with. The final solution was to remove the BASIC language chip, which took up 8K space. To begin with, the basic chips were removed from the Atari 800XL and a socket was put in itís place, where the final 8K EPROM was placed . This was a great deal of careful work, and it was later discovered that we did not need to remove the BASIC chip. In fact all that was necessary, was to clip the power lead to the BASIC chip, and then piggyback solder the EPROM on top of the BASIC Chip. A couple of jumper wires were also required to finish the installation of the EPROM over the top of the BASIC chip. If you turned on the modified Atari 800XL without the SpectraView I cartridge plugged in, there was a small program that would display horizontally scrolling colored lines, which would mean the computer was OK and the EPROM chip was installed correctly over the top of the BASIC chip . Once you plugged in the SpectraView I cartridge, the entire system would work as an information display system.
DEL Compu-Cable Systems second product was to trim down the SpectraView I software and to remove some of the features, so that the program would fit into 16K. This second product, called the SpectraView II, did not required a modified Atari 800XL computer. Therefore you could buy the cartridge only, and purchase an Atari computer separately. The Graphics Tablet did not have anyway to type text onto the pictures that you would draw . Therefore, the Graphics Tablet cartridge was de-compiled and it was found that there was enough blank space on the cartridge so that software could be added to allow a user to type text over pictures. Typing software was developed, again in 6502 assembly language, and a new EPROM was burnt, and then soldered over the top of the Graphics Tablet chip.
The first SpectraView I system was sold to a small cable company in Zainesville, Ohio in 1984. The SpectraView I and SpectraView II were sold over the course of 1984 till about 1991 or 1992. If I remember correctly, (and I probably donít), but I think the SpecrtraView retailed for about $2000 US and the SpectraView II cartridge retailed for about $900 US. An exact count was never kept, but at one point, it was estimated that DEL Compu-Cable Systems sold a total of about 4000 SpectraView I and SpectraView II. Since then DEL Compu-Cable Systems was re-organized and became Display Systems International, Inc. in 1991. During the years, other platforms and programs were developed for the Atari ST and the Commodore Amiga. Ultimately, DSI has been developing software for the IBM PC under windows. DSI started with a program for Windows 3.1 and continued with versions for Windows 95, Windows 98, Windows XP and Windows Vista.
Thanks for your interest and I hope this helps you.
Display Systems International, Inc.
 I suppose Dale mention Atari CX-77 Touch Tablet.
 It must be memory banking simmilar to Supercartridge by OSS ("Action!", "BASIC XL", etc.). Compare to http://www.retrobits.../osscarts.shtml
 This method sounds strange today but not in 1983...
 If you put SpectraView 1 in regular (unmodified) Arari 800XL you also can see only these raibnow bars.
 I suppose it means "Atari Artist" cartridge.
Edited by nosty, Tue Jun 30, 2009 5:07 PM.