Good afternoon to all,
I am starting the process of selling off some of my vintage computer systems, so as to not burden anyone I leave behind.
The systems I list here are available for viewing in Bedford, NH, just west of Manchester, NH. Anyone interested can send me an e-mail message and we can set up an appointment for you to visit. Cash and Carry, of course, and reasonable offers will be considered.
Altair 8800c — $2500
I constructed this system early in 2019. I built the front panel and front panel interface boards, and soldered up the backplane. The rest of the boards were purchased assembled and tested. You can see the Altair 8800c story here: https://deramp.com/altair.html The system is fully tested and working, currently using virtual Altair disk drives via the Deramp application. Plenty of documentation.
Single 8 inch disk drive in a dual drive cabinet — $500
This physical disk drive has been paired with the Altair 8800c in the past. Works fine. I included will be an 8 inch disk drive that used to be in this cabinet until the power supply failed. I believe this drive can be repaired. Included will be another 8 inch drive that is the wrong form factor to fit into the cabinet. Purchased on eBay, untested.
Altair 680 — $2000
I acquired this system on eBay back at the end of 2018. It was not working, but a bit of troubleshooting discovered bad ram which was replaced. The least significant LED of the address display does not light, but I’ve tested that the proper signals are there. I simply did not want to risk changing out the LED. This system comes with the 4-slot riser, but the connectors are not yet soldered in. No add-in boards. Plenty of documentation.
Complete SWTPC 6800 clone system from Corsham Technologies — $400
I acquired this system from Bob at Corsham in the middle of 2018. It is the complete setup, with the full 64K ram and the virtual disk drives. Documentation available at Corsham Technologies: http://www.corshamtech.com <http://www.corshamtech.com/>
Northstar Horizon — $800
I purchased this system on eBay as a running system. From time to time I had problems with the top 8K ram on the Horizon 64K ram board. The 64k ram board has been replaced with a Compupro Ram 17 (or clone), works great, no problems. I will include the glitchy Horizon 64K ram board. FYI, a Deramp Virtual Sector Generator works great with this system, eliminating the need for hard sector diskettes. https://deramp.com/vsg.html
Thanks for listening!
smp
- - -
Stephen Pereira
Bedford, NH 03110
KB1SXE
Good afternoon to all,
I am starting the process of selling off some of my vintage computer systems, so as to not burden anyone I leave behind.
The systems I list here are available for viewing in Bedford, NH, just west of Manchester, NH. Anyone interested can send me an e-mail message and we can set up an appointment for you to visit. Cash and Carry, of course, and reasonable offers will be considered.
Altair 8800c — $2500
I constructed this system early in 2019. I built the front panel and front panel interface boards, and soldered up the backplane. The rest of the boards were purchased assembled and tested. You can see the Altair 8800c story here: https://deramp.com/altair.html The system is fully tested and working, currently using virtual Altair disk drives via the Deramp application. Plenty of documentation.
Single 8 inch disk drive in a dual drive cabinet — $500
This physical disk drive has been paired with the Altair 8800c in the past. Works fine. I included will be an 8 inch disk drive that used to be in this cabinet until the power supply failed. I believe this drive can be repaired. Included will be another 8 inch drive that is the wrong form factor to fit into the cabinet. Purchased on eBay, untested.
Altair 680 — $2000
I acquired this system on eBay back at the end of 2018. It was not working, but a bit of troubleshooting discovered bad ram which was replaced. The least significant LED of the address display does not light, but I’ve tested that the proper signals are there. I simply did not want to risk changing out the LED. This system comes with the 4-slot riser, but the connectors are not yet soldered in. No add-in boards. Plenty of documentation.
Complete SWTPC 6800 clone system from Corsham Technologies — $400
I acquired this system from Bob at Corsham in the middle of 2018. It is the complete setup, with the full 64K ram and the virtual disk drives. Documentation available at Corsham Technologies: http://www.corshamtech.com <http://www.corshamtech.com/>
Northstar Horizon — $800
I purchased this system on eBay as a running system. From time to time I had problems with the top 8K ram on the Horizon 64K ram board. The 64k ram board has been replaced with a Compupro Ram 17 (or clone), works great, no problems. I will include the glitchy Horizon 64K ram board. FYI, a Deramp Virtual Sector Generator works great with this system, eliminating the need for hard sector diskettes. https://deramp.com/vsg.html
Thanks for listening!
smp
- - -
Stephen Pereira
Bedford, NH 03110
KB1SXE
Group,
Ive got a tape here from what I believe to be a VM system. The
structure is unknown to me, although I can possibly take a stab at it.
Lots of data between tapemarks that seems to consist of a number of
records that start out something like this (translated from EBCIDC):
> 00000000 02 43 4d 53 46 30 30 30 31 31 32 30 35 31 31 32 |.CMSF00011205112|
> 00000010 34 37 30 37 36 30 31 32 32 32 31 31 30 31 31 31 |4707601222110111|
Another example:
> 00000000 02 43 4d 53 46 44 41 54 41 20 5f 4e 55 4c 4c 5f |.CMSFDATA _NULL_|
> 00000010 3b 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 |; |
> 00000020 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 20 | |
The data itself appears to be a bunch of 80 character card images.
I found a mention on the old yahoo groups H390-VM discussions, but no
clarity was ever shed on the subject.
Does anyone know about this tape format?
--Chuck
Seems like rather than going through MUSIC/SP it'd be easier to just fire
up VM/CE 1.2 (which is VM/370 r6) and use CMS TAPE (which is present)
directly from the CMS UI. You can probably attach the file you've got as a
tape device; not entirely sure Hercules will like the format, but it
wouldn't hurt to try.
Adam
I'd like to get an ISA based transputer card. Something with multiple
cpus (so not the B004).
A B008 or one of the clones that accepts multiple TRAM modules would be
ideal (https://www.geekdot.com/inmos-b008)
It doesn't have to be TRAM. I saw this multi-cpu board on ebay.ie but a)
it's more than I was hoping to spend b) I can't find any info on it.
Whatever I get I want there to be reasonable docs and archived
software: https://www.ebay.ie/itm/234283597489
Suggestions on what to look for welcomed. I'm in no rush and good things
come to those who wait. I'm in the USA but have family in the UK and go
there often so I'm looking on ebay.co.uk
Thanks!
Hello all,
as it will be soon of importance to us, I am seeking for the systems
engineering manual and drawings, well, everything about the IBM 727 tape
drive (not the 729!). I especially need the module locations charts and
the module schematics.
I see that there is the CE manual on bitsavers. Eventually, the other
manuals are available somewhere, too?
Christian
I have a non-functioning VT100. I think it is failing in the POST during the
RAM check. I don't know for sure because I can't get it to light up the LEDs
on the keyboard, however I used my logic analyser (a HP1630G) to see what
values were written to the UART to send to the keyboard and I see it sends
the values FF then 1, 2, 3, 4 and finally 5. The last value corresponds to
the RAM test so I am fairly confident the RAM test is what is failing.
I have disassembled the VT100 ROM and if I have understood it correctly it
zeroes out the RAM (high address to low) and then for each address (low
address to high) it tries first to read back the zero and then writes 0xAA
to the location and tries to read that back.
I am also confident the 8080 is working OK because I was able to capture an
address trace on the ROM that showed it executing the program as per the
disassembled ROM.
My problem is getting the logic analyser reliably to tell me how each RAM
chip is being addressed and what data is being read or written. I am seeing
strange values for the addresses (sometimes) and I am not sure I have setup
the logic analyser correctly. I have read the datasheet for the 2114 chip
and I am not entirely clear that I have understood it correctly. Here is how
I have set it up:
Trigger on the -ve edge of Chip Select (pin 8)
Capture A9-A0 as the address
Capture WE as an indication of Read or Write
The timing diagrams show the write cycle where the WE signal and CE signal
seem to transition at the same time and the data may be only valid a bit
later then the CS -ve edge. But this may just be me not knowing how to read
the datasheet. Using the +ve edge of CS seems no better.
Is there something I am missing about how to analyse how the RAM chips are
being used?
Thanks
Rob
Not quite computer tech but I figure this is the best place to ask:
Does anyone recognize the display tech that was used on the Concorde's in-cabin display?
Examples:
https://samchui.com/wp-content/uploads/2016/02/CON15.jpghttps://samchui.com/wp-content/uploads/2016/02/CON16.jpg
The display had fully-formed digits and letters, and showed either Mach and Feet, or Temp and MPH. Some pictures show the display in green and others show it in orange - which of course were popular monochrome CRT colors, yet the display looks too "flat" to be a couple CRT's. Those colors were also popular for Electroluminiscent displays which matches the evident "flatness" but I'm not sure I've seen any EL's with fully formed digits like this with no visible segmentation?
I want to guess it was individual digits back-projected - which was a popular control-theater display tech at the end of the 20th century - but I can't rule out, say, really well-done edge-lit character plates. In any event there doesn't seem to be any visible jitter up and down between digits that I might expect with either of those technologies.
The "FEET" display in the above-referenced JPG's shows some artifacts at the left and right edges which might be a clue?
Some pics of the BA Concorde interior had a simple 15-segment and 7-segment green LED display. Don't need help with that one 🙂.
Tim N3QE
