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carlsson
April 29th, 2006, 11:48 AM
I think I've posted about a local guy who used to be a PET/Commodore reseller etc. I went there before Christmas and picked up a bit of VIC-20 stuff, which is my main area of interest. Back then I didn't know exactly what he had to offer, but I took mental notes and sent out a mail to the cbm-hackers list. I got about a dozen requests for various items.

Today I finally went back there, equipped with my list of wants. My car is a tiny Skoda Felicia (as noted in the other thread), so it can not swallow too much. Also the shipping costs to distribute these machines across half the world are a bit intimidating, so I only picked up what people really asked for. I have at the same time got three requests from people on the list to bring a mini-van and load it with anything they can find.

http://www.cbm.sfks.se/pics/pet1.jpg
From left to right:
* PET 200 a.k.a PET 8032-SK
* PET/CBM 720 (256K)
* PET 3032

http://www.cbm.sfks.se/pics/pet2.jpg
With tape and wires: PET 8296-D (partly broken)
Two PET/CBM 610 (128 and 256K) a.k.a. B128/256 (?)
Two D9060 and two D9090 hard disks, plus a loose 3000 series motherboard

In the chair: three 8250LP dual diskdrives, one Corvus hard disk and two interface boxes for those hard disks.

I also got a bag full of IEEE-488 cables and power cables, the former a bit hard to obtain today I believe. I also picked a few items for my own liking, probably I'll at least keep one of the 610's since it is relatively small and takes composite video output in the same 5-pin DIN layout as VIC-20/Atari/TI-99 (?) etc.

All the computers were checked so they boot up to Basic, but not further than that. We found a few 7xx systems that didn't boot at all, and a few 610's that either had a bad keyboard or dropped into monitor (bad ROM?).

The good (bad?) part is that the guy has more than twice as much stuff left, in particular full-height IEEE-488 drives like 4040, 8050, 8250, 2031 etc. As you see, I only picked 8250LP's, partly because that was what people asked for and they are a bit smaller (and maybe lighter) to ship than the full-height versions. He also had boxes of unused 5.25" SSDD disks, c:a 200 in each box. I suppose there is some interest in those too, but I would've have wanted DSDD. There was a small selection of 5.25" HD disks though. And a few (two at least) Victor systems etc.

Phew. Now I'll gotta sort through which items goes to who.

carlsson
April 30th, 2006, 01:53 PM
A small update:

* The CBM 720 lasted for a few hours before the screen gave up its ghost. I'm happy I didn't pack it and ship to a customer who'd been rather disappointed. Perhaps there is one more of these systems, but the customer may just as well choose not to get one, since these 7xx machines had been stored in a garage and may all be of dubious reliability.

* The 8296D is still broken, but I'm toying with the idea if the monitor is compatible with the 720 monitor, and in that case could be replaced.

* One D9090 hard disk was fully functional. One D9060 was made functional after swapping boards and reseating some ROM chips. Two D9060 drives are still non-functional.

* Two 8250LP are fully functional, the third only operates on drive 1. But there were more of these to select from, so I can get a different unit.

* The loose 3032 motherboard works like a charm.

I haven't tried the Corvus drive yet, since I don't quite know how to attach or operate it. There should be a 32 pin flat cable between the "hardbox" and the hard disk unit, but I don't have anything like that. The hard disk also seems to be useable as a VCR (?), having "VCR Remote" and "Video in/out" plugs.

Terry Yager
April 30th, 2006, 02:30 PM
The 'VCR' jacks are for backups. Corvus used (cheap, easily available) VCR systems as a low-end backup for thier hard drive systems, rather than more expensive tape-backup systems of the time.

--T

carlsson
April 30th, 2006, 02:42 PM
Aha, cool. The need to backup a hard disk didn't strike me as obvious as the need to use a hard disk as a video recorder.. although I should've thought it was way ahead of time to achieve this in the early 1980's. :-)

Terry Yager
April 30th, 2006, 03:19 PM
The capacity & reliability was soon out-run by the alternate tape systems, which also rapidly dropped in price, rendering the VCR option quickly obsolete.

--T

carlsson
May 1st, 2006, 07:38 AM
* The CBM 720 lasted for a few hours before the screen gave up its ghost.
Or perhaps it is the motherboard as well. I can't determine, but it only makes a tiny hiss. The monitor has the same pinout as in the 8296, but they don't seem to use the same refresh ratios etc.


* Two 8250LP are fully functional, the third only operates on drive 1.
I tried to swap chips (2x 6502, 2x 6532, 1x 6522) but no improvement so far. I accidentally put in all chips in reverse position, but it doesn't seem to have broken any chips more than they were before. :eek:

However, I have also noticed that the 128K CBM-610 (B128 ) seems to have a broken IEEE-488 interface, but boots properly in other ways. The 256K unit can access the same drive with the same cable, so it must be the computer.

Oh well, the more I test this stuff, the more faults I find, but at least in the case of 8250LP and CBM-610, there were a few more (functioning or partly broken) units to pick from.

carlsson
May 1st, 2006, 11:26 AM
the 128K CBM-610 (B128 ) seems to have a broken IEEE-488 interface
One man's (computer's) loss, the other man's gain. Thanks to Commodore, they tended to put a lot of easily broken chips in sockets (but not on all machines, even of the same model). I replaced the 6526 CIA from the 610 with the same chip from the broken 720, and now both 610's have a working IEEE interface again. :D In theory, I have a broken C64 which could've donated a 6526 too, if the other chip wouldn't have worked.

carlsson
May 1st, 2006, 12:00 PM
Besides, unlike the earlier PETs and also later VIC/64, some of the graphic characters are positioned in a rather bizarre fashion. The computer has two modes: NORM (upper + lower case) or GRAPH (graphics + upper case).

Pressing shift+L in NORM mode results in a capital L, which translates to a |_ in graphics mode. However, shift+L in GRAPH mode translates to a cross, which in text mode equals capital V.. :roll: This anomaly translates into at least a handful letters/graphics, perhaps even more on this unit which is localized with Swedish characters.

carlsson
May 6th, 2006, 12:16 PM
* One D9090 hard disk was fully functional. One D9060 was made functional after swapping boards and reseating some ROM chips. Two D9060 drives are still non-functional.
Out of the two broken drives, at least the noisy one has a working disk. I temporarily swapped boards again, and after threatening it with a format (!) command, it sprung to life. The disk is full of sequential files referring to something called WVKOM (sounds like a bulletin board system), but still reporting more blocks free than it should as being empty, so I'm making a vain attempt to validate it. Not that it matters much, as long as at least one interface board contains problems, but the potential receivers are handy with soldering irons so they can replace damaged RAM chips or whatever is the problem.

The more silent one doesn't do an iota..

Update: the noisy one seems intermittent, now it doesn't respond neither

carlsson
June 12th, 2006, 02:31 PM
Yesterday I picked some more items, and again looked at the boxes full of mainboards (3032, perhaps some other model) and ditto boxes of loose keyboards of various types. I know there is a circuit by Nick Hampshire in PET Revealed (1979) that discusses how to get composite video from the user port or internal video, and there is one more similar circuit out there.

While I'm the worst person to do hardware hacks, I'm toying with the idea to craft small (heh) power supplies, put the motherboard and a keyboard in a box (something like a CBM B-series in size, I suppose) and add a small circuit to get composite video in the back. I have no idea how much work it would take, which kind of shell (metal?) would be needed and what the manufacturing costs would be, but it would be a cool hack to make a few, perhaps up to five such units, given that the motherboards themselves are OK. All the other connectors for tape, IEEE etc are already on the board.

Jorg
June 13th, 2006, 08:28 AM
Oh man!

What all treasures are hidden in the beautiful country of Sweden..

carlsson
June 14th, 2006, 01:43 AM
Not generally. I live in a city where the number of vintage computer/video game finds on flea markets, second hand shops and alike the last five years can be counted on the fingers on one hand. We're a half dozen people, some more collector-like than I am, who have agreed this is true. So, in view of that, this old PET reseller with a basement full is a big break from the usual.

If I had more storage myself, I might buy it all out in one go for better access. I've even toyed with the idea to rent an extra storage room from my tenant association.

carlsson
June 29th, 2006, 02:07 AM
Hm, I picked up a 700-series cartridge "Handic Word Result" with one of the machines. I don't have a functional 700, so I tested it on a 610 (low profile) but it didn't boot.

Yesterday, I carefully opened the cartridge, and found a socketed ROM chip. Not too spectacular, if it was sold commercially they would have manufactured real ROMs. The interesting detail was the part number of the chip. I looked it up, and it seems to be a character ROM, no more, no less. The board is machine made and not really room for an additional chip. Perhaps someone at one point has replaced the application ROM with a character ROM chip, but I can't see why. Nevertheless, I understand why the cartridge won't boot, as the character ROM probably doesn't contain the required startup sequence.

There is a box worth of other 700 series cartridges I could pick up, but I don't know if it is useful. Maybe I'll try one more, as I have one 610 with 256K and ROMs labeled 700 series.

carlsson
July 25th, 2006, 01:08 PM
I haven't tried the Corvus drive yet, since I don't quite know how to attach or operate it. There should be a 32 pin flat cable between the "hardbox" and the hard disk unit,
Now I have assembled all parts and all information! After finding a suitable power adapter for the Hardbox and the proper flat cable, it still didn't work until I read some reseller (!) documentation mentioning some switches on the underside of the front panel. After setting them properly, the hard disk is operating!

This Corvus + Hardbox are intended for PET 8032/8096 series. First, I tried it with a CBM 610 (B128 ), but transfer was dog slow and often the directories were suddenly abrupted. Then I tried with a PET 600 (8296-SK) and it runs in lightening speed. Apparently there is some major timing differences on the IEEE implementation on these two rather different systems.

These Corvus disks came in capacities of 6, 12 or 18 MB. A simple directory listing suggests 496 blocks used and 192 blocks free. Those are standard Commodore blocks, giving a total capacity of 172 kB. That is floppyesque. However, the disk can be partitioned into up to 64 user areas. I'm unsure how to find out, but 172*64 = 10.75 MB, which would be more like it.

Hmm, found a program called USERS. It shows that this hard disk is divided on three users:

system: 350 kB
meny: 50 kB
dms: 5193 kB

Interesting.. now I got to play some more.

carlsson
July 25th, 2006, 02:50 PM
http://www.cbm.sfks.se/pics/corvus.jpg
At one time, this might've been a hot system for company use. On the other hand, I believe it is post-IBM PC, so mainly interesting for already existing PET users. The hard disk contains some register program, but it is protected with a hardware dongle that I don't own so I can't try it..

The floppy drive is only there for size estimations; I didn't have enough power cables to have everything running at the same time.

Bill_Loguidice
July 26th, 2006, 06:49 AM
Phenomenal finds and great job getting it to work. I'm quite jealous. So far I've only collected two SuperPet's (one complete) and an 8050 dual disk drive. The 600 is one amazing looking system case-wise...

carlsson
July 26th, 2006, 07:20 AM
Yeah, the PET 200/600/8296 and subsequently CBM 700 series are said to have been designed by Porsche. I don't know, but if it is so, maybe it makes them even more valuable. :-)

Next attempt will be to use an IEEE interface on the VIC-20 and see if this Corvus disk accepts it. The software to select user, format disk etc of course are written for PET 8000 series, but being written in Basic, it should be easy to convert if required. Mostly I'm interested to see if it is the CBM-II series that has slightly different timing, or if every IEEE implementation is different. Those units developed by Commodore themselves probably have enough error margin to function with all interfaces, but third-party systems tightly developed for one type of computer may not have as much fault margin.

carlsson
July 26th, 2006, 01:00 PM
It took some fiddling - these IEEE cables don't daisy-chain so easily - but eventually I got the Corvus to work with VIC-20. Of course, it has no CATALOG command so one has to LOAD"$",8 but it is reasonably fast and no obvious glitches. It got me curious, and I tried a CBM-II (610) again. All access using device number the "old-fashioned" way works fine.

I've figured out that one selects area (partition) with PRINT#1,"L:area" and one can change user with U:user. Some commands are prefixed with an exclamation mark !U: but yet I don't know what it means. There are other commands like LOCK: and UNLOCK: and probably a lot more I haven't seen. The docs I have are reseller material, so not very technical. Maybe I can find more stuff elsewhere, although I doubt Internet in this case.

carlsson
October 10th, 2006, 12:56 PM
Four hard disks in one picture:

http://www.cbm.sfks.se/pics/corvus-2.jpg

At the moment, only the upper two - 6 and 20 MB - function reliably. One of the other drives emits error codes and I barely got it to work. The last drive doesn't even light its LEDs. At a later time, I'll investigate those two and see if I can find something obvious (maybe swap drives, as both are of the 10 MB model).

nige the hippy
October 10th, 2006, 03:26 PM
Yeah, the PET 200/600/8296 and subsequently CBM 700 series are said to have been designed by Porsche. I don't know, but if it is so, maybe it makes them even more valuable. :-)

It was Porsche Industrial Design, started by the brother (I think) of the car man.

I think the third coolest looking bit of computer hardware ( the coolest being the cray-1 (designed to be sat on, whilst teraflops go on behind you), and the second being those terminals that look like Kenny from south park, but white (anyone know who made them??) .

carlsson
October 10th, 2006, 03:41 PM
There is a woman, Ira Velinsky in New Jersey who is credited for the patented design of these PET/CBM computers. I've recently read that at one point, Commodore "fell out with" whoever Porsche they were working with. Maybe this woman was working for Porsche Industrial Design, and at the time things screwed up, she left the company to finish the work for Commodore instead?

Maybe if you have access to a basement + garage full of these darlings, you don't find them so cool looking anymore. It is like a rare coin. If you have one, you value it highly. If you have five, you keep track where you've laid them. If you have a hundred identical rare coins, you may one day use a few for change.

Terry Yager
October 10th, 2006, 04:30 PM
I've seen that discrepancy before. Some sources claim a Porche design, while others credit Ms. Velinsky. Your possible explanation is certainly plausible.

--T

apple2fan
October 10th, 2006, 09:27 PM
My dad used to have a commodore 64 when they first came out. He bought It at a Kmart, I think. It cost him $500. A lot cheaper than an apple II back then!
Not sure what happened to It though.:(

carlsson
October 23rd, 2006, 12:12 PM
One of the other drives emits error codes and I barely got it to work. The last drive doesn't even light its LEDs.
No luck. I swapped controller boards, and got the opposite behavior with respective drive. The drive porition of the controller consists of two cards on a passive backplane. I even tried to swap only one of those, but no difference. Probably both drive mechanisms are "best before", but different states. I'll try some more, by swapping the actual drives in case the one that doesn't seem to power up at all is due to power problems.

By the way, look: four Z80 chips on one circuit board!
http://www.cbm.sfks.se/pics/corvus-3.jpg

carlsson
October 23rd, 2006, 12:31 PM
Is this likely to be a ST412/506 compatible interface, just like in those Commodore 90X0 drives I fooled with earlier? One drive says model number 5012H and one says 5018H, but both supposedly are 10 MB. The make is International Memories Inc, USA.

http://www.cbm.sfks.se/pics/corvus-4.jpg

rolandboedeker
October 30th, 2006, 10:14 PM
Hello, I'm searching for a keyboard of my 8032-SK computer. Does anybody know where I can find it?

carlsson
October 31st, 2006, 02:52 PM
Eventually, I'll be able to help you. I will send a PM with more details.

carlsson
October 22nd, 2007, 07:21 AM
Resurrecting an old thread with a fresh photo taken yesterday, after I had carried down a load of broken equipment into my basement. Now I only have a few working computers upstairs. The table is rather ugly looking, but fills a purpose and would even allow me to sit and work at the table if I wished to (and connected a few power cables).

http://www.cbm.sfks.se/pics/pet-bord.jpg

MikeS
November 16th, 2007, 05:24 PM
Is everyone aware of the World of Commodore event in Toronto on Dec.1, 2007?

m

Jorg
November 17th, 2007, 01:58 AM
Resurrecting an old thread with a fresh photo taken yesterday, after I had carried down a load of broken equipment into my basement. Now I only have a few working computers upstairs. The table is rather ugly looking, but fills a purpose and would even allow me to sit and work at the table if I wished to (and connected a few power cables).

http://www.cbm.sfks.se/pics/pet-bord.jpg

Owww..VERY nice picture