Recent content by P-man

Well, I think MOS was planting the seed of microcomputing by engineering out all the mundane stuff you had to work out yourself on earlier systems. Things such as having microcode in rom for interfacing the keypad, the 7-seg LED displays, a cassette interface, serial interface (!), and routines...

hi all, Recently got hold of a pretty impressive example of a 70's homebrew computer system. The original owner got hold of a release model MOS KIM-1 and designed and built their own S-100 interface card, built an enclosure and keyboard, added ram card and serial terminal card to make for an...

hi all, as the title suggests - looking for one of these if you have one and can mail it, please let me know!

Excellent information thankyou. The rom has a blank label, so that's no help.. but please find a dumped ZIP attached here, plus photos :) Ok, so it looks like i need to find this System Support 1 PCB, there's space in the chassis right next to the existing drives so a Gotek 8" doohickey...

hi all, Recently picked up this seemingly unused TEI chassis containing a good group of entirely CompuPro cards installed in it, with two 5.25" drives. All cards are Godbout/Compupro branded. Looks like theres 256k of ram on 4x 64k SRAM cards, an Interfacer 1 a floppy controller, and the...

I have an STB multi-function card with ram and it has an unusual RTC chip - the SAF3019P.. I can't find any timer/setclock utilities for it, has anyone seen this before?

I would like this for an XT project, message sent!

You shouldn't put anything at C000 anyway, c800 is the safest universal location that will work from PC through x86 up to Pentiums. DiskOnChip modules *only* work between C800/D000/D800 to avoid conflicts.

Found this piece of paper for the above mentioned speed displays in an old case, useful for minuszerodegrees!

For anyone reading this in the future - after looking at the schematic and what it was doing in-circuit I figured a 2N3055 would work in its place, and indeed it does now work fine replacing the 171-1 transistors :)

Just to add that this morning I repaired the PSU by replacing the two bad 171-1 transistors (one had a B->C short, the other was leaking C->E). As the -12v transistor had shorted, I decided to also replace its ua723 regulator at the same time. I checked the state of some of the caps in the...

hi Jon, Thankyou for the schematic for the PSU though that will be a help! Currently i have a bad 171-1 transistor on the -12v rail. On removing the others to service the rest of the psu board i found the other two measure differently from each other as well. Do you know if a more easily...

I thought I would make a separate thread for this new system i got (mentioned in another thread about the psu). I recently got a an Intel i661 chassis and it came with a manual (145340-001) but I wasn't able to find this online so i scanned it myself. It is just JPGS though so it needs turning...

hi all, Just picked up an Intel i660 (Multibus) chassis with a bunch of cards but the psu is bad. I am figuring it out, but would be nice to have a schematic.. seems like my chassis/PSU is from 1978 but the rest of my SBC cards are from late 1984.. any hints appreciated!

hi all, I have an LED mhz speed display in a case I am building right now marked TD-38S , I did not see listed on minuszerodegrees, but several that are close. I used K-568 for the diagram to help me suss out where the normal and turbo pins were for each unit. I took photos of the group of...