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NEC PC-8201A Laptop

by billdeg
Total messages in this thread: 2
Updated: [ Correction - there is no Kyosel company ] 11/03/2009
For the past six months I have been doing a lot of reading and research on the early laptop computers. The NEC 8201A is not the first, but it's an excellent example of what "laptop" meant in 1983. The 8201 is actually a re-packaged Kyotronic KC-85 (named for it's Intel 8085 processor), and also is it's third sibling, the Tandy TRS 80 Model 100. Future issues of this web site will feature many more of these early laptops. Some call the Kyotronic "Kyrocera 85" but my Kyotronic has a company called "Kyosel" on the label. ?? The name must have changed to "Kyocera" at some point soon thereafter. ?? The real expert on this subject is Evan Koblentz of and he is a great source on laptop history. NEC PC-8201A">... [ read more ]

Saving Memory to Disk Commodore PET

by billdeg
Total messages in this thread: 2
Updated: [ Copy Machine Lang PET Cassette Programs ] 07/22/2010
Here are the directions for saving a block of memory (as in a program written to memory from a machine language program loaded from cassette) to disk. 1. format your disk. I have a 2040 attached to my Commodore PET 2001-16N OPEN 1,8,15 PRINT#1,"N0:DISKNAME, 01" 2. Load the program you have, know where it's been loaded. For example, BREAKOUT is loaded by cassette into memory locations 033F to 1491 SYS 1024 - command to load TIM monitor from READY prompt of PET .S "0:BREAKOUT",08,033F,1491 this means on drive 0, create a file called BREAKOUT on unit 8 that consists of what's in memory locations 033F through 1491. Drive 0 on unit 8 is the right hand drive of the model 2040. The disk drive should activate and create the file. Reboot. Load the program load "breakout",8,0 (assuming the disk is still in the right side drive) Enjoy.">... [ read more ]

Teletype ASR 33 Woes

by billdeg
Total messages in this thread: 4
Updated: [ ASR33 Update - Printing ] 10/25/2009
I knocked over my working teletype ASR 33. Now it does not work correctly. After locating all of the pieces, I carefully re-installed as much I could. I was only partially successful.
The typewriter part of the Teletype model ASR 33 responsible for moving the print head over one space at a time.
I do know that the teletype is sending data correctly from the keyboard to the computer through the serial cable, and the computer is receiving the commands. Output from the computer to the teletype is received and the print head itself is printing the correct characters. The problem is that the print head is not moving horizontally along the line, it just says in place and types each character on top of itself.
If I">... [ read more ]

PET 8032 with 64K mem expansion

by billdeg
Total messages in this thread: 1
The Commodore PET 8032. This unit has the 64K Memory Expansion Installed.
Because I don't have a working PET 4032 motherboard I decided to install a PET 64K memory expansion kits in one of my 8032's instead. The memory expansion board consists of 32 4116 chips. The Motherboard's 6502 is moved to the memory board. I have two PET 8032's - SN 01026512 (works, has a missing 4 key) and SN 01026512 (works, brand new keyboard, 2 Amp fuse mod). I chose the latter for the 64K upgrade because it was in better shape. The physical installation went just fine, the kit had all of the parts. A p">... [ read more ]

TRS 80 Model 1 with Composite Mod

by billdeg
Total messages in this thread: 1
I am working on hacking a TRS 80 Model 1 that will work with a composite monitor. I found this thread from 2003 about it. http://www.classi...uly/017197.html More detail to come.">... [ read more ]

S-100 Buffered Prototype Board

by monahan_z
Total messages in this thread: 2
Updated: [ I/O board ] 10/23/2009
Andrew Lynch and I have just completed the layout of a new S-100 Prototype Board that is designed to help take away the initial drugery of building S-100 prototype boards. We have laid out the board so all the address and data lines are buffered through 74LS245's or 74LS244's. Most of the common S-100 bus control and status signals are also buffered. So the user can right away get down to building useful circuits without the bus connection/IC overhead. Also the board is arranged so a daughter piggyback (no S-100) board can be attached via a series of connectors. This way you can have cheap simple test boards made before you "burn" your own real (more expensive) S-100 board. Currently we are getting 10 of these boards made for ourselves. If there is a strong demand we could possibly do more for others. We don't have an exact price yet but it should be south o">... [ read more ]

Burroughs L7000 Computer

by billdeg
Total messages in this thread: 1
I have been contacted by a jewelry store in Newark Delaware who has a Burroughs L7000 computer to donate. I have helped make arrangements to have this picked up and delivered to the MARCH museum in Wall New Jersey, part of the InfoAge complex at Camp Evans. pics">... [ read more ]

1975 Microcomputer Directory

by billdeg
Total messages in this thread: 1
The COSMAC Microkit 1 (RCA) was an early 1801 microcomputer kit from 1975.
A directory of microcomputers was compiled by Robert M. Grossman, Associate Editor of EDN Microprocessor Design Series Volume II. Robert wrote an article titled µC Systems Directory: where have all the µP's gone?. NOTE: µC = "microcomputer" and µP = "microprocessor.
More 1975 microcomputing devices: The Microcontroller (Scientific Micro Systems), the M6800 (Motorola), and the MicroPac 80 microcomputer (Process Computer Systems)
MITS is listed as a manufacturer and so are a lot of very interesting other companies, some I never heard of, but I am missing the page that lists the models">... [ read more ]

Selected 1975 Microprocessor Diagrams

by billdeg
Total messages in this thread: 1
RCA 1801, Intel 8080, MOS 650x, and Motorola 6800 diagrams">... [ read more ]


by billdeg
Total messages in this thread: 1
Did you know that Compute! was "Compute." for the first two issues? For future reference here's what I have on hand: vol 1 issue 1 Fall 1979, issue 2 Jan Feb 1980. vol 2 issue 7 Nov / Dec 1980 vol 3 issue 1 Jan 1980 vol 3 issue 9 Feb 1981 -through- issue 16 Sept 1981">... [ read more ]

MITS Altair 8800a

by billdeg
Total messages in this thread: 1
Here are some pictures of my MITS Altair 8800a model. This unit has been on loan with Dan Roganti who has restored power to the unit by replacing some caps (I believe). More to come in early 2010.
The relatively rare Altair 8800a model was advertised by MITS for less than a year. Note the front plate variation compared with the original model. Click image for larger view.
See also front panel project: http://vintage...rowse_thread.cfm?id=317">... [ read more ]

Vintage Computer Festival East 6.0

by billdeg
Total messages in this thread: 1
Pictures from the Vintage Computer Festival East 6.0 held September 12 and 13th at the Info Age Science Center in Wall, NJ USA
William (Bill)Dromgoole's "..Ohio Scientific Superkit with a homebrewed power supply and no case, 25x25-character display, and external parallel ASCII keyboard. The Superkit consists of model 500a CPU board, model 480 backplane, and 440b video card. Also installed are a model 430b cassette I/O interface with D/A and A/D converters and model 420c memory cards. .." One of my favorite exhibits.
Pictures">... [ read more ]

Examine using Front Panel - problem

by billdeg
Total messages in this thread: 2
Updated: [ Examine using Front Panel - correction ] 09/25/2009
This is a note to self. I have an Altair mentioned elsewhere on this web site, SN 220744K, and the front panel has been mod-ed to with both IMSAI and Altair front panel connectors so either CPU interface card can be used. When the Altair card in installed, examine does not work. Here is a substitute for examine in the mean time assume you're starting from 000 000 but you want to examine what's in c000. deposit load the following: 000 303 jmp [a7, a6, a1, a0 up] 000 000 lower [all down] 000 300 upper [ a7, a6 up] = c000 reset put all toggles down single step = watch for a15, a14 up = c000 now that you have jumped to c000, you can use the examine next. NEXT: try system with imsai CPU card, see if examine works. If yes, then it's the cable, if no, then it's the front panel (someplace). See also post about the power supply capacitor for this system, needs replaci">... [ read more ]

Processor Tech General Purpose Module

by billdeg
Total messages in this thread: 4
Updated: [ Further attempts to fix PT GPM card ] 10/18/2009
For my own reference, I took some pictures of Bill Sudbrink's Processor Tech General Purpose Module card, which is similar to mine except that he made some modifications to protect some of the F000+ memory when CUTER and NorthStar DOS try to use the same spaces. Here are the pictures I took: Processor Tech General Purpose Module Mods for NS DOS and CUTER Of course now I have a problem with my CUTER program, I must have blown an IC. Next - find and repair the bad component. ">... [ read more ]

Televideo TS-816

by billdeg
Total messages in this thread: 1
I took this system out for a spin, it had been 4 or 5 years. Still works great. Here are some new pictures.
The Televideo TS-816 has no internal disk drive, only a tape unit, which is used for backup and restore operations. Fortunately the hard drive will still boot and support multiple terminal operations. I used the serial port from a laptop to load the BASIC program ELIZA from console mode and then ran the program on separate (Televideo) terminal in user mode.
">... [ read more ]
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