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Digital VT 102 Terminals

by billdeg
Total messages in this thread: 5
Updated: [ Repairing dead vt102 ] 09/19/2012
Digital VT 102
Digital VT-102 Terminal
Picked up 4 of these, I will make one working unit, sell/donate the rest. More Pics">... [ read more ]

A Sick IBM 5170 AT

by billdeg
Total messages in this thread: 3
Updated: [ IBM AT 5170 update ] 08/26/2012
The IBM AT Model 5170 front-left
Display when the system was working perfectly, all software running normally.
I removed the battery. Now the system does not recognize the hard drive, and the display mode is in 40-columns. Unlike the IBM PC/XT, the system configuration is stored in memory ROM requiring battery power.
The IMI 5012H is I am told a clone of the Shugart ST-512, which is a type 1 drive.
I verified that the jumpers on the motherboard were OK. I was not able to find the manual for the IMI 5012H. NEXT: Run the AT diagnostics, guess/assume that the drive type is "1", and see what happens. If it's not a type">... [ read more ]

CorData Technologies, Inc. Cordata PPC

by billdeg
Total messages in this thread: 3
Updated: [ Next steps ] 08/26/2012
Here's a rare one...The 1985 CorData Technologies, Inc. cordata PPC computer. The logo on the machine looks similar to the Corona Data Systems' logo, but there's no reference to this model within the Corona catalog. Corona is kind of close to Cordata...Maybe they changed their name late in the game? Pics">... [ read more ]

Cybernetic Systems Inc. Mathiputer

by billdeg
Total messages in this thread: 2
Updated: [ Mathiputer Diagnostics ] 08/26/2012
The 1975 Cybernetic Systems, Inc Mathiputer. Click image for larger view.
This device is intended to instruct children on basic math skills. Not functional, needs to be cleaned and tested. more to come.">... [ read more ]

TRS 80 Model 4P Repair

by billdeg
Total messages in this thread: 1
This is a program I use to test RAM on a TRS 80 Model 4 / 4P. It will id whether you have 64K or 128K and run through a test pattern on the screen to test video RAM as well. I forget the company who made it. Note the "128K" in the upper right corner.
I learned something while repairing a customer's two TRS 80 Model 4P computers. If you have 128K installed and the system does not boot (gives you CRC error during POST of the OS disk), try removing the back 64K RAM (remember to move the jumper back to 64K mode) before you assume it's the disk drive. There have been times when I thought the CRC error was always due to disk drive not being able to load the OS, when it was actually the RAM in error. It's a lot easier to find and replace a bad RAM chip, even if you have to do it one at">... [ read more ]

MITS Altair 8800 Power Supply

by billdeg
Total messages in this thread: 1
Pictured is a MITS accessory box. No I do not have original MITS power supplies for sale or otherwise.
ALTAIR 8800 original power supply specifications (at the end): (From Dan Roganti [CORRECTED]) T1 transformer Output = 8VAC, 8A This is used to power the TTL logic on the cards in the backplane(+5V). It was very underpowered when many of the slots were populated with cards. T2 transformer (dual output) : This is just a strange part just so they can have a separate 8VAC power supply. This is a "nice-to-have" part but it's entirely unnecessary. Because the Front Panel can't operate without power on the CPU and the CPU can't operate without power on the Front Panel. They just had some unwarrant">... [ read more ]

Hewlett Packard 9835B

by billdeg
Total messages in this thread: 2
Updated: [ Testing the HP 9835B ] 08/03/2012
HP Hewlett Packard 9835B
The Hewlett Packard 9835B computer. Click image for larger view.
Untested. More to come. pics ">... [ read more ]

Hope 9 - July 13-15 2012

by billdeg
Total messages in this thread: 2
Updated: [ History of Portable Hacks Talk at HOPE 9 ] 08/01/2012
Mimeo Apple 1
The MidAtlantic Retro Computing Hobbyists exhibited single board computers and trainers at the 2012 HOPE 9 convention in NYC July 13-15. Among the systems exhibited was this replica Apple 1 computer. Click image for larger view.
HOPE 9 Mid Atlantic Retro Computing Hobbyists Exhibit
Here's Jeff telling tales of computing days past to an interested booth visitor. Jeff helped man the exhibit booth for 12 hours at a time, the club owes a lot to him for sharing his knowledge and his dedication to the club. Click image for larger view.
... [ read more ]

PERQ System F Workstation Computer

by billdeg
Total messages in this thread: 1
Three Rivers Computer PERQ System F Workstation
The PERQ System F workstation computer is I believe the first commercial workstation, if you don't include the Xerox Alto.
She's filthy and missing the keyboard but this is quite rare. pics">... [ read more ]

Tandy TRS 80 Model 16B

by billdeg
Total messages in this thread: 1
TRS 80 Model 16B
Here is a TRS 80 Model 16B, capable of running both Model II / 12's Z80 software and Motorola 68000 XENIX.
Ran a quick test. Lit up the RIFA cap, but I noticed that the system flashed the expected request for a boot disk. Should be restorable. Keyboard status unknown. pics">... [ read more ]

Digital VT-103

by billdeg
Total messages in this thread: 1
Digital VT 103
Digital VT-103 Terminal with dual cassette drives.
So far I have downloaded the manual, more to come. More Pics">... [ read more ]

Diagnosing Error Codes Franklin ACE

by billdeg
Total messages in this thread: 3
Updated: [ Franklin ACE RAM - MK4315N ] 07/30/2012
The Franklin ACE 1200 computer was an Apple II clone. This system has the version 2.3 ROMs. Click image for larger view.
This is the persistent error code that appears on the screen when attempting to boot an Apple II diskette in drive 1.
NEXT: Determine what the error codes mean, and repair. I am guessing I have bad RAM, 3715 could be a RAM memory address, the other codes probably represent diagnostic values that explain the error, the pointer or stack value at the time of the error, or something like that. We'll see. Here is a link to the Apple Monitor program. The Franklin was cloned from the Appl">... [ read more ]

ADDS Regent 20

by billdeg
Total messages in this thread: 1
ADDS Regent 20 Terminal
This is an ADDS Regent 20 terminal, the only one I have seen with no numeric keypad. This terminal can be set for current loop or RS232 operation. Click on image for larger view.
This guy needs some serious cleaning but it actually powers up and displays a prompt. More to come. Pics">... [ read more ]

ME1702a EPROM Programmer

by billdeg
Total messages in this thread: 1
Built by a friend from the kit, I am now the proud owner of a ME1702a ePROM programmer unit. Martin Eberhard did a spectacular job on this device. I insisted on using an original 70's ZIF socket, which needed a squirt of DeoxIT, but other than that it worked perfectly the first time. Now what to program, what to program???? Next I plan to put MINOL on 7 1702a's, see how that goes.">... [ read more ]

Adventure!

by billdeg
Total messages in this thread: 3
Updated: [ Log Dump from Adventure Play ] 07/18/2012
This screen shot shows the use of Digital's OS-8 to enter commands. The first command demonstrates how to load BASIC. The second command, "RUN RKB0:ADVENT", loads and runs Adventure! This and the images to follow are photos taken while running on a PDP 8/e computer using a VT 52 display. That's me in the screen reflection.
Opening credits screen of Adventure!
Adventure! is probably the most famous "interactive fiction" program (text adventure game) written for a computer. Adventure was originally written for the PDP 8 computer, I believe the PDP 8e, but I am not 100% sure about that. The whole interactive fiction genre has received a lot">... [ read more ]
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