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IBM 4459 PC/AT Tempest

RJBJR

Experienced Member
Joined
Feb 17, 2011
Messages
453
More digging through the junk. A 5170 motherboard in a hardened case. Case is aluminim and around 3/16" to 1/4" in places. The monitor is a hardened version of the PC, the keyboard is an 83-key PC style but with indicator lights like an A/T 101 keyboard and a different plug.

The computer is sitting on it's storage case which houses everything in a weatherproof metal box.

This was an old FEMA unit that I got from Moser Electronics in 2000.
 
Ah now this brings back some memories! What we in the USAF called an EMR AT. Had these things at what used to be called the 6920th Electronic Security Group in Misawa Japan back in the Mid 80's. Heavy little buggers to! These used to get so hot that the RAM and ROM would actually work there way out of the sockets and we would get a job called out because the computer stopped working. Just had to remove about a 100 screws holding the lid down. Just had to push them back down into the sockets and all would be ok again. As for the Hard Drive they were on removeable cartridges and if I remember they were 44Meg Drives. The OS they ran was Xenix 286. Brings back some memories these things. Also had an EMR XT as it's little brother!
 
the keyboard is an 83-key PC style but with indicator lights like an A/T 101 keyboard and a different plug.

Just a little correction: that is the standard 84-key AT layout. Quite a bit different from the old 83-key XT style.

It's interesting how they did the expansion slots on that thing... it looks like the standard slot layout inside, just with extensions plugged into the normal cards and routed out to the back panel. I'm guessing probably the reason they changed to a DE9 connector for the keyboard was because the standard DIN connector had no provisions for retaining screws?
 
Very neat. So the system actually runs inside of the thing it's sitting on? By tempest, does it say that on there somewhere? I'm guessing that it's tempest compliant although not 100% sure what changes were made beyond sticking it in that box. What's the J1 round connector for? (can't tell from the picture and not familiar with the model of system).
 
Just a little correction: that is the standard 84-key AT layout. Quite a bit different from the old 83-key XT style.

Certainly is the 84-key, I shoulda realized that....

It seems everything is just re-routed to the expansion slot, I have never taken this down farther than the pics so don't know exactly which cards are in there or if there are any real differences between them and a normal 5170.
 
Very nice. Hate to have to pay shipping on that... :)

You wouldn't happen to have a 7531 somewhere in your junk pile would you? :D
 
Very neat. So the system actually runs inside of the thing it's sitting on? By tempest, does it say that on there somewhere? I'm guessing that it's tempest compliant although not 100% sure what changes were made beyond sticking it in that box. What's the J1 round connector for? (can't tell from the picture and not familiar with the model of system).

The box is a storage box that acts as a table. It houses the whole system for shipping/storage. The connector on the back is for monitor power. The monitor I have has a standard 110v plug plus an additional plug for the back of the computer that would need to be wired back to original(assuming the 110v mod isn't OEM).

This is the TPC 4, Tempest is not printed on any of the labels, just the TPC designator.
 
You're missing the most important part of a Tempest setup--the shielded and screened CRT.

It's a Tempest monitor, TPC1 mono.

I guess FEMA only upgraded the CPU from TPC1 to TPC4 and didn't upgrade the monitors from TPC1 to TPC4, that would explain the extra round power plug for the TPC4 monitor that was in the storage box.
 
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What's the "K/B Inhibit" selection on the key port for? Smart of them (or the previous owners) to put the "Two Person Lift" sticker on it. It might be funny if you say, "I strained my back on an AT while ignoring the two person lift sticker.":)
 
What's the "K/B Inhibit" selection on the key port for? Smart of them (or the previous owners) to put the "Two Person Lift" sticker on it. It might be funny if you say, "I strained my back on an AT while ignoring the two person lift sticker.":)

locks the keyboard out of the system without shutting down the unit
 
Ah now this brings back some memories! What we in the USAF called an EMR AT. Had these things at what used to be called the 6920th Electronic Security Group in Misawa Japan back in the Mid 80's. Heavy little buggers to! These used to get so hot that the RAM and ROM would actually work there way out of the sockets and we would get a job called out because the computer stopped working. Just had to remove about a 100 screws holding the lid down. Just had to push them back down into the sockets and all would be ok again. As for the Hard Drive they were on removeable cartridges and if I remember they were 44Meg Drives. The OS they ran was Xenix 286. Brings back some memories these things. Also had an EMR XT as it's little brother!

The Air Force always had the coolest stuff to play with(and still do) while we ARMY grunts had to make do with whatever Jimmy Carter saw fit not to throw away. I used my first computer in the ARMY, it was a FADAC, had to program it with paper tape and it's output was on a teletype. That computer was replaced with a TI-99 <g> things have come a long way since then.
 
If memory serves me this was basically a 5170 motherboard placed in a shielded case. This has all the covers, port openings Etc. covered with the metallic mesh to form Electro Magnetic Resistance shielding. The 9 Pin DE-9 KBD was terminated into a 5 pin DIN inside the case. These systems were usually inside an SCI facility and processed Top Secret information. Hence the EMR AT name. Didn't want sensitive info "leaking" out. At least the ones we had were. I guess FEMA got these as left overs from USAF depot. And yes it was a 2 man lift. As I said they were quite heavy. ;)
 
I disassembled it because I wanted to see what tape drive it had. It's a Syquest SQ-312 10MB that is attached to an Adaptec card that has an BIOS, seems the unit may have booted either from the tape drive or the Frontier Industries network card that also has a BIOS. The other cards are an IBM serial/paralell card, an IBM HDD/floppy controller, and an IBM mono/paralell card. The floppy is an IBM 360k drive, seems odd for a 5170. Lots of screws and a couple clips hold the whole thing together.

The main board is a regular 5170 Type 1 with 512k of memory.

It would be nice to have the color monitor but it came with the mono and to keep it original it will stay mono. The mono monitor seems to be, from outward appearances, an IBM 5151 that is tagged as an TPC Display 1, Model 4451, with a heavily shielded video cable and heavy duty 110v plug. The Type 4 color monitor, which would have been EGA ? (from what I have read) besides having the shielded video cable would have plugged into the back of the computer with a round metal plug. At least I have the round metal plug <g>, suppose I could take an 5154 and hack the plug and put a EGA card in it, but will keep this original so whoever ends up with it gets it complete.

The whole unit is a hernia looking for a place to happen. Almost forgot to mention the official FEMA black rotary dial desk-top phone that has it's own special cubby hole in the case <g>
 
When googling for similar units for sale (didn't see any) it does look like that was a standard feature for that model line for having the removable hard card system for the OS/data. Although yes I suppose one could have tried to do a bootp diskless setup which would be pretty spiffy.

Do you have a picture of the whole setup with the phone? That system is too cool.
 
Just a little correction: that is the standard 84-key AT layout. Quite a bit different from the old 83-key XT style.

It's interesting how they did the expansion slots on that thing... it looks like the standard slot layout inside, just with extensions plugged into the normal cards and routed out to the back panel. I'm guessing probably the reason they changed to a DE9 connector for the keyboard was because the standard DIN connector had no provisions for retaining screws?

While it's apart , here are a couple pics of the expansion extension. Lots of resistors....
 
When googling for similar units for sale (didn't see any) it does look like that was a standard feature for that model line for having the removable hard card system for the OS/data. Although yes I suppose one could have tried to do a bootp diskless setup which would be pretty spiffy.

Do you have a picture of the whole setup with the phone? That system is too cool.

Just looked at the phone, ITT push-button from the 70's/80's, it is just a phone , doesn't plug-in to the computer but has a couple "not-secure" markings.

Not sure what other pics with the phone? Gotta put the beast back together to get any more assembled pics...
 
Oh yeah the Frontier card. Forgot about that one. But my old memory can't remember how this thing booted. Oh well don't drop it on you foot!
 
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