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The below info is a little old, and hasnŐt even been looked at for a while. We just got a digital camera so I should be able to get some new and better pictures, and IŐll try to update the rest of the page too. 6/18/00

IBM Series/1

Well, I've got a Series/1 minicomputer. It's huge! The company I got it from upgraded to the RS/6000 platform, which can run Series/1 software under emulation. They needed to get it out of the way, so they posted a message in the newsgroup, and I have a hard time passing up free computer equipment. I ended up bringing home over a half ton of computer, which was three 19" racks, two terminals, a box of 8" floppies, and a huge pile of repair manuals. There were four 4967 hard drives, weighing over 200lbs each and with a capacity of 200MB, a 4963 hard drive that weighed about 170lbs and a capacity of 68MB, a 4956-K00 CPU with 2MB RAM, two 4959 expansion units, an 8" floppy drive, a 4968 autoload tape drive weighing 80lbs and a capacity of 85MB, and a 4969 tape drive weighing about 180lbs. These are not normal tape drives, these are huge reel-to-reel drives. And the system runs on 220v, so I had to drag the cord to the next floor up(barely reached) to test it out after bending the plug to fit the outlet for the dryer. I could only plug in one rack, which at the time had a 4959, the CPU, the 8" floppy drive and the 68MB hard drive. Problem is that I had no idea how it works, but I plugged in a terminal and started it up. It's noisy! But it didn't IPL from the floppy drive, I'm not sure if it was the floppy drive or a bad disk. Nothing showed up on the terminal, the head on the disk didn't move that I could tell, and the system appears to freeze part way through the IPL. Now I have completely changed the setup of the system, and it now has a 4959, CPU, floppy drive, 4968 tape drive and a 4967 hard drive in one rack, I got rid of one of the racks and the third rack has the large tape drive stuck in it. The 4969 wouldn't come out of the rack due to a stripped bolt that needs to be drilled out. To make things worse, I lost my grip on the rack while taking it to the basement and it fell half the way. From the outside, there wasn't any obvious damage, but inside the diagnostic panel had several switches broken off and one of the control cables had snapped. So now I have a broken tape drive stuck inside a rack, making both of them useless, and it takes up a lot of room! On to the photos... This got a little confusing, so I don't even know what I did any more...

This is the CPU card, with 2MB of RAM and an FPU. The blue connector on the bottom left is to connect to the IPL and programmers consoles, the connectors on the edge next to the blue on is for connectors that attach memory cards.

This is the channel repower card, which acts as a bridge for the expansion channel between the CPU and an expansion unit like a 4959.

This is the interface for the 4968 tape drive, which stores about 85MB on 2400 feet of half-inch magnetic tape. And no, I don't mean those little cartridge drives like you use for backups. I mean big reels full of tape. I think the 4968 can use 8, 10 and 12 inch reels.

I have no idea what this is, so if you know let ME know... I can't find a matching drawing in either of the MLD binders and IBM's part number ID line is a 900 number...

This is a 4 line async communications card, needs the 8-line card to control two of these with a Y cable.

Well, there were a few bad blocks on the floppy I used in the digital camera, so this card doesn't have a big image. But from my QuickCam photo, it looks to be the 8 line asynch communications card. Connects to the 4-line card above.

This is the 4978 terminal controller. I have over a dozen of these cards, but only two terminals! I'm still looking for a 4978 terminal emulator for either Mac or PC.

This fun little thing is called a feature programmable multi-line communications card! I have no idea how to use it or what it does, but it's there.

This card controls the 200MB 4967 hard drive.

This card controls the 4963 hard drive. And it looks like I screwed up again, so there is no nice picture of this either...

And this is the controller for the 8" 4964 floppy drive.

This is the actual disk of the 4963, without all the control and power supply circuits in the way. And of course the frame is missing... The entire unit is similair in size the the 4967.

This is a 4967 drive, also without the control and power supply circuits which sit in a removeable upper frame about 6 inches think. Both drives pictured here are at OMSI in the electronics lab.

Well, that's everything for now.

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