test-drb January 2014

test-drb@ccmp.vtda.org

224 participants
263 discussions

Intel MDS 225 system being auctioned by Chicago Transit Authority

by brad＠bettercomputing.net

I just bought one of those off ebay for $50. ?Shipping was a killer though. ?Very nice machine. ? Just wish I had a boot disk for it. Brad Sent from Samsung Mobile <div>-------- Original message --------</div><div>From: Jason T <silent700 at gmail.com> </div><div>Date:01/02/2014 1:46 PM (GMT-08:00) </div><div>To: "General Discussion: On-Topic Posts Only" <cctech at classiccmp.org> </div><div>Subject: Re: Intel MDS 225 system being auctioned by Chicago Transit Authority </div><div> </div>On Thu, Dec 12, 2013 at 3:48 PM, Colin Howell <colin.d.howell at gmail.com> wrote: > The Chicago Transit Authority is auctioning off a whole load of > miscellaneous stuff (including a couple of rail cars!). One of the items > being auctioned is what appears to be an Intel MDS 225 "Blue Box" (4 MHz > 8085A system) complete with an MDS 720 disk expansion unit and some sort of > Control Data hard disk. > > The specific lot is here: > > http://ricklevin.nextlot.com/public/lot/15005194?section=photos Despite being local *and* placing a low bid on the lot, I completely dropped the ball (mouse?) and forgot about the closing. Did anyone here end up with this fine blue machine?

11 years

SWTPC TVT-II

by brad＠bettercomputing.net

Hey everyone, I'm a fairly middle-weight collector based in Squamish, BC. I have about 70 machines total, a few of which are projects that I'm seeking advice/help on. One of them is an SWTPC TVT-II CT-1024 terminal. I bought it a couple of months ago, complete on ebay. I've tried to read as much documentation on these as I can find, but there are a few things I can't figure out. I've posted a few videos of it -- including this one: https://www.youtube.com/watch?v=c2rX10-m8GQ Initially when I turned it on, I got just garbled screen. The first monitor I attempted to hook up to was my Apple III, which apparently can't handle it at all. Then I went to my Commodore 1702 and 1084, and I can adjust things enough to make out a picture and characters, but it's repeated several times, as you can see in the video. On the first few powerups I'd see the occasional flickering of a full field of questionmarks, but it wouldn't stay. I learned about the voltage trimmer on the PSU and have trimmed it to 5V exactly, and now when I turn the unit on, the field of question marks comes up and stays. There is a switch I've discovered (none of them are labelled) that causes that field to disappear. I think this puts the unit into terminal mode. The keyboard is connected to the serial card (I think there is a connector on the motherboard where it could go also if you didn't have that). I also played with some trimmers on the motherboard that adjust horizontal position and so on. Anyway, what you see in the videos up to the most recent one is the most I can make it do. It doesn't seem to respond to keystrokes, and the documentation I have is limited or a bit over my head. Mainly I'd like to figure out why the screen is so messed up. Much appreciated if there are any of you out there familiar with these old timers and would have an idea where to begin looking. Brad

11 years

2BSD and RL02 (was Re: Need DEC BC80J-20 cable)

by ethan.dicks＠gmail.com

On Fri, Jan 3, 2014 at 4:17 PM, Mark J. Blair <nf6x at nf6x.net> wrote: > I'm just getting started in DEC stuff in general and RL02 drives in particular. I'm > putting together a PDP-11/44 system, and I hope to try running both RT11 and > BSD on it. The 11/44 has split I&D so you can go with 2.9BSD or 2.11BSD. Generally speaking, you'd probably want to go with 2.11BSD because you can. > Would a two-drive system be sufficient, or would I need more storage space? > I have four RL02 drives in unknown condition, but I was only planning to rack > up two of them with the PDP-11/44 and a Kennedy 9610 9-track tape drive. My experience is that I was able to fit the base install on the first RL02 pack, but there wasn't room to pull the sources and rebuild the kernel without more storage. Even so, 20MB total was kinda tight, maybe too tight. Back when this hardware was current, it was IIRC easy to plunk 2BSD onto one or two RK07s (28MB each). When I started playing with simh 15+ years ago, it was easier to define an RP03 and install into one big 60MB pot (which is how I helped find a simh bug long ago). You can give it a try now with simh by practicing with a couple of 10MB image files and the 2BSD distro tape images. It's an authentic experience in terms of the approach you'd have to take and the commands you'd have to type (without bad blocks and tape errors to pull you astray). If it fits on 2x RL02 in simh, it'll be the same on real hardware. That reminds me - you have to have error-free packs. DEC used to sell RL02-EF packs for use with UNIX (RT-11 can mark bad spots on the disk and if they aren't in the first tracks or if there aren't too many, you can mark those sectors allocated and work around them. Not so with BSD). For RT-11, even a single RL02 is plenty of space. I used develop applications on an 11/23 and an RL01 was enough for the OS and all my code. > My PDP-11/44 pile came with an RL11 board and the cable from it to the > first RL02 drive. It doesn't have a bulkhead fitting; it just goes from > the controller directly to the connector that plugs into the back of an > RL02 drive. I haven't looked at the cable carefully yet, but I can > examine, measure and photograph it if that would be helpful to anybody > else in this thread. The bulkhead bracket was convenient but not essential. To get out of the CPU cabinet, you almost certainly have a flat 40-pin cable, then the transition connector, then probably the usual drive-to-drive round cable, but just laying in a line, not bolted to your rack. It will work just fine but there's a risk of kinking or pinching cables if you move the drives around a lot (the bracket has a spot to screw down a tab on the shield of the round cable as a strain relief with either a 6-32 or 4-40 machine screw). I know I have at least 1-2 bad cables from excessive flex/pinching (I've thought about cutting them at the point of physical damage and trying to make one or two of them into a BC80M cable since I have the right crimper for those Berg pins). > BTW, I am looking for drive ID lenses for my RL02 drives. I need a "1" and > a "2", and I could either buy them outright or trade "0" lenses for them. My > RL02 pile came with three "0" lenses and a "3". My recollection is that it was common to have 1-2 drives, but not 3-4 (for reasons of cost), and as systems were consolidated, there were more "0" plugs than the others combined. I've thought about molding replacements or even 3D printing them (they'd be suitably light-transmissive if made from natural ABS or especially natural or clear PLA) but I haven't tried making an STL of them. There'd be a risk of the fingers snapping off and getting stuck in the switch mechanism, but I think an ABS drive plug that was subjected to the acetone vapor treatment would firm up nicely and be resistant to the layers separating. Anyone care to make up an engineering drawing of the plug with tolerances in the 0.1mm range? -ethan

11 years

Keeping a Heavy Machine on a Domestic Suspended Floor (UK)

by robert.jarratt＠ntlworld.com

I recently bought a lovely PDP11/45 in a H960 rack, with the CPU, a Unibus Expansion box and an RK05 drive. I am guessing the whole thing must weigh at least 100Kg, possibly 150Kg or even more (my worst case estimate is 200Kg). I am concerned whether the floor of the upstairs room where I now have it can bear the weight. I have placed it right next to a load bearing wall to ease the strain on the joists. Can anyone tell me what sort of weight a normal UK upstairs floor can bear? If my guessed weight is anything close to the limit I will weigh parts of the machine to get a more accurate idea of the actual weight. Thanks Rob

11 years

BNC Video out and LCD monitor with VGA D-Sub video in

by hp-fix＠xs4all.nl

You'll need a Sync On Green to VGA converter to separate the sync signals. -Rik -----Oorspronkelijk bericht----- Van: "Andreas Holz" <aswood at t-online.de> Verzonden: ?4-?1-?2014 09:24 Aan: "cctalk at classiccmp.org" <cctalk at classiccmp.org> Onderwerp: BNC Video out and LCD monitor with VGA D-Sub video in Hello all, how to connect a HP 9000/300 with RGB BNC video out to a modern LCD monitor, which has only a D-Sub VGA video connector. Can I simply use a classic BNC to VGA cable just reverse connected? Since from 2015 on there will be no new monitor supporting VGA singnals anymore what we have to do to connect our old workstations? Andreas

11 years

VAX 4000-500

by me＠GarrettMeiers.com

I purchased a VAX 4000-500 last month and am pretty excited. I've only owned MicroVAX'es in the past, and this is the first larger VAX I've had.. Although, it's more of a medium-sized VAX. :) ?Came with an Infoserver 100, and a R400X? Expander with three drives. I haven't fired it up yet, but was told it all works. I have the DSSI cables, and need to do a little reading before I connect these up, and fire it up. Any pointers for working with this setup -- in particular DSSI and the Expander, would be appreciated. https://www.dropbox.com/sc/4ziahrtsp5lw57l/fy1lCpcoar#/ ?Thanks, Garrett Meiers Founder, BitHistory.org & President, ConsulNIX, LLC www.BitHistory.org www.linkedin.com/in/theunixguy

11 years

Need DEC BC80J-20 cable

by charlesmorris800＠centurytel.net

On Jan 3, 2014, at 5:18 PM, cctalk-request at classiccmp.org wrote: > From: Ethan Dicks <ethan.dicks at gmail.com> > To: "General Discussion: On-Topic and Off-Topic Posts" > <cctalk at classiccmp.org> > Subject: Re: Need DEC BC80J-20 cable > Message-ID: > <CAALmimndRqNj0eDbaYdyFGz+VsO0pikpHK_1O5wn4R-n2eV5sg at mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > On Fri, Jan 3, 2014 at 1:35 PM, Al Kossow <aek at bitsavers.org> wrote: >>> BTW, Continental Computers answered my quote request with they can >>> "let it >>> go for $145"... that's about four times what I expected to pay for >>> one! >> >> The BC80M listed for 57.50 should work fine. > > That one looks to be 6' (BC80M06) which is the only length I've seen > in person. They also have a BC80M25 for three times as much. > >> You'll probably have to fiddle with the big drain cable on the >> controller end. > > I remember that big fat braid. ISTR it was not easy to find a > convenient place to bolt that down on a BA23. > > -ethan I am sure I can find a place to fasten it, even if I have to modify the braid (or the chassis) slightly... Anyway I was thinking of just bending over and paying the $57.50. Until I got to "standard 9-13 day shipping $15.00" and it goes up from there. Postage rates have really gotten ridiculous and the companies (except McMaster-Carr who are quite reasonable for shipping) are adding on their profit too. Perhaps I can locate some surplus multiple twisted pair cable and carefully solder the ends to a header connector. There are 13(?) twisted pair differential signals and the rest are no-connects or grounds. As Henk pointed out, some of the trouble may be the 6' of unshielded ribbon cable (which is also smaller gauge than the twisted pairs)... -Charles

11 years

No Console on MicroVAX 2000 if Disk Not Plugged In

by robert.jarratt＠ntlworld.com

I have come across a strange problem with my MicroVAX 2000. If the hard disk is not plugged in I get absolutely nothing on the console, as if the machine was dead. I have perused the technical documentation and I cannot find anything that describes this behaviour. Does anyone know why it might do this and which signal(s) prevent the console coming up? I need this to be able to do some initial testing of a basic emulation of the RD5x disks with an FPGA. Thanks Rob

11 years

older memory, tested on memory tester

by sales＠elecplus.com

No reasonable offers refused J Desktop: 8MB 60ns 11 16MB 60ns 78 32MB 60ns 301 64MB 60ns 19 64MB PC100U 169 64MB PC100E 16 64MB PC133U 17 64MB PC133E 8 128MB PC100U 152 128MB PC100E 11 128MB PC100R 12 128MB PC133U 179 128MB PC133E 9 256MB PC100U 71 256MB PC100E 8 256MB PC100R 11 256MB PC133U 20 256MB PC133E 14 256MB PC133R 8 512MB PC100R 6 512MB PC133U 7 512MB PC133E 1 512MB PC133R 23 1GB PC100R 2 1GB PC133R 3 Laptop: 128MB PC133S 2 256MB PC133S 9 512MB PC133S 3 Cindy Croxton Electronics Plus 1613 Water Street Kerrville, TX 78028 (830)792-3400 phone (830)792-3404 fax AOL IM elcpls _____ No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3658/6971 - Release Date: 01/02/14

11 years

Commodore PET 2001 with screen problem

by brad＠bettercomputing.net

One other project I'm having some difficulties with is a Commodore PET 2001 that I've had for 10 years. In that time, turning it on only ever produced a 'blank' raster screen, as in this video: https://www.youtube.com/watch?v=m5Rkwu858zA For years I assumed the computer was basically dead and kept it on static display. But just recently I acquired a good working 2001-16, and discovered that I could use its monitor with the 2001-8. I discovered the standard garbage screen, and after acquiring a whole bunch of rare NOS 6540s, and some 6550 RAMs, was able to get the 2001-8's motherboard fully functional. The screen however remains the same. I have connected it to the other working PET to no avail. I have even used the working PET's own cabling. So my problem is basically the video board. I've fixed the brightness control but that's as far as I've dared go given the voltages involved with a CRT. Wondering if anyone has any other ideas on where my problem could be. Thanks!! Brad

11 years

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test-drb January 2014