I thought I share my work:
Over the past three years I've made some S100 boards for my Altair 8800 build. Two years ago I've bought an empty optima case from Ebay. To make
a working 8800a computer I worked on the PCB's and the frontpanel (artwork). First the artwork. Luckily there's a good scan online (https://www.vintage-computer.com/images/altairfrontpanelscan.jpg) for
designing a new frontpanel. I've made a new version in GIMP by selecting, tracing and pixel editing to get a clean frontpanel for printing. I think it's a nice attempt if I say so myself.
I've printed the frontpanel on aluminum so there's a metal feel to it. I've integrated the logo strip because the printing company (photo on aluminum) can print transparent pngs.
Then the pcbs. When I started with the pcbs I never made anything in Kicad. Now I'm somewhat of a pro
. Some of the schematics from MITS are messy (as you probably know) so for
example with the 8080 CPU I've bitmap converted the pcb scans to trace the tracks after I've made the schematic from the manual. I did this with every pcb. The boards are not a replica or a pixel
perfect clone. This is because I chose for a schematic / PCB approach rather then a scan / gerber. an advantage is that you can easily make changes. (For example, A 8080 CPU pcb change with the clock mod)
8080 CPU (works, KiCad replica. needs cpu clock tuning. Schematic cleaning necessary):
Front Panel (works, KiCad replica. Schematic cleaning necessary):
For the main board I've used scans available on the internet. This board is also remade with Kicad:
Then I needed ram. I like using old boards and old ICs so I started with a 1k static ram board. It's a simple board but I don't have the pcb scans. The board is finished and working. Protect / Unprotect works.
MITS 1k static ram board (works, Kicad new design based on pictures. No original traces):
For the PSU I used an original PS DB supply pcb and bought transformers to use the system with 220volt. I've scans available when I stripped the PCB but it's better to use a switching power supply these days.
I worked on my Altair for a very long time. Now I'm at the point where I can play kill the bit on my machine. I'm not a electrical engineer. Just a network IT-er with a passion for old machines. Keep that in mind when looking at the Kicad images
At this moment I'm working on serial communication. The schematics for a 2SIO board are messy and I've made a prototype from the manual with problems. I would love to get pcb scans from a bare pcb. That would be really great. In the last couple of weeks I've made two
other serial boards. The Solid State Music IO-4 and a MITS SIO-A board. These two boards are arrived last week and I'm waiting on the last ICs to test the boards. The traces on the IO-4 are autotraced so not that nice. For now that's enough.
MITS SIO-A:
Solid State Music IO-4:
The last project I'm working on is the Tarbell Cassette Interface. I've a finished schematic plus a PCB traced from the manual (very difficult thing to do!). The KCS mod is not included. I need to test this pcb in the coming weeks but a working serial board is my priority.
Tarbell Cassette Interface 1001:
I don't know if people are interested in the PCBs. I will setup a site when people are interested. I know Grant's very nice clone is neater but a more affordable alternative is desirable I think. If you do not want to work with 74xx logic, I would like to refer to the Altair 8800c
Maybe someone can help me with bare pcb scans from 1k static ram, SSM IO-4 or the 2SIO card. I would love to trace those boards to Kicad perfection and also find the problem with the 2SIO board.
Regards,
Martijn from Holland.
Over the past three years I've made some S100 boards for my Altair 8800 build. Two years ago I've bought an empty optima case from Ebay. To make
a working 8800a computer I worked on the PCB's and the frontpanel (artwork). First the artwork. Luckily there's a good scan online (https://www.vintage-computer.com/images/altairfrontpanelscan.jpg) for
designing a new frontpanel. I've made a new version in GIMP by selecting, tracing and pixel editing to get a clean frontpanel for printing. I think it's a nice attempt if I say so myself.
I've printed the frontpanel on aluminum so there's a metal feel to it. I've integrated the logo strip because the printing company (photo on aluminum) can print transparent pngs.
Then the pcbs. When I started with the pcbs I never made anything in Kicad. Now I'm somewhat of a pro
. Some of the schematics from MITS are messy (as you probably know) so forexample with the 8080 CPU I've bitmap converted the pcb scans to trace the tracks after I've made the schematic from the manual. I did this with every pcb. The boards are not a replica or a pixel
perfect clone. This is because I chose for a schematic / PCB approach rather then a scan / gerber. an advantage is that you can easily make changes. (For example, A 8080 CPU pcb change with the clock mod)
8080 CPU (works, KiCad replica. needs cpu clock tuning. Schematic cleaning necessary):
Front Panel (works, KiCad replica. Schematic cleaning necessary):
For the main board I've used scans available on the internet. This board is also remade with Kicad:
Then I needed ram. I like using old boards and old ICs so I started with a 1k static ram board. It's a simple board but I don't have the pcb scans. The board is finished and working. Protect / Unprotect works.
MITS 1k static ram board (works, Kicad new design based on pictures. No original traces):
For the PSU I used an original PS DB supply pcb and bought transformers to use the system with 220volt. I've scans available when I stripped the PCB but it's better to use a switching power supply these days.
I worked on my Altair for a very long time. Now I'm at the point where I can play kill the bit on my machine. I'm not a electrical engineer. Just a network IT-er with a passion for old machines. Keep that in mind when looking at the Kicad images
At this moment I'm working on serial communication. The schematics for a 2SIO board are messy and I've made a prototype from the manual with problems. I would love to get pcb scans from a bare pcb. That would be really great. In the last couple of weeks I've made two
other serial boards. The Solid State Music IO-4 and a MITS SIO-A board. These two boards are arrived last week and I'm waiting on the last ICs to test the boards. The traces on the IO-4 are autotraced so not that nice. For now that's enough.
MITS SIO-A:
Solid State Music IO-4:
The last project I'm working on is the Tarbell Cassette Interface. I've a finished schematic plus a PCB traced from the manual (very difficult thing to do!). The KCS mod is not included. I need to test this pcb in the coming weeks but a working serial board is my priority.
Tarbell Cassette Interface 1001:
I don't know if people are interested in the PCBs. I will setup a site when people are interested. I know Grant's very nice clone is neater but a more affordable alternative is desirable I think. If you do not want to work with 74xx logic, I would like to refer to the Altair 8800c
Maybe someone can help me with bare pcb scans from 1k static ram, SSM IO-4 or the 2SIO card. I would love to trace those boards to Kicad perfection
and also find the problem with the 2SIO board.Regards,
Martijn from Holland.
