• Please review our updated Terms and Rules here

Best home Mainframe

A

acorn_1401

Experienced Member
Joined
Mar 1, 2023
Messages
116
Location
South UK
Very random thread:

What is the best mainframe (by your justified opinion) what the best mainframe you can have that one might be able to have at home - e.g. while it might be possible that someone has say a 1401/360 or something at home it isn't likely but might have say a PDP8 or something that they picked up and able to maintain at home that doesn't require that they have mega bucks.

It doesn't require you to have this system, but that there are enough of them that one being at a home isn't so out there e.g. PDP1's I think there are only handful still around and they are all in one place (CFH) tho might be wrong on that so don't have a go at me on the one point.
 
Weirdly, I can count multiple people who own IBM S/390 family machines. It is with one hand but it's still a lot more people than you would expect.

A PDP-8's and 11' are not mainframe systems. It's a minicomputer. In that case a machine like the IBM System/36 and AS/400 are appropriate and I can count the number of people I personally know with machines like that with two hands.
 
Depends on what you're willing to call a "mainframe'. And what your resources are. Recall that there are people who have installed theater pipe organs in their homes. I believe that one of the Apple founders had that set up for a home in Woodside, though I don't know if it happened.

I do know that Jacques LIttlefield had constructed an auditorium with a custom instrument (Ruffatti?) at his home in Portola Valley. Jacques also collected tanks (the military type)...

Depends on what your resources look like.
 
Well yes I wanted to put some budget on it as while not a mainframe but one of the guys from Microsoft has a difference engine (No2) in his house (it was in his office at one point but last time I read it was at his house) that cost him a few million.

the idea of it was more along the lines of a device (maybe a bad title of the thread used) that was at your home that is big enough that most people would only think live in museums.
 
acorn_1401 said:
the idea of it was more along the lines of a device (maybe a bad title of the thread used) that was at your home that is big enough that most people would only think live in museums.
Click to expand...

Computer-Guy.jpg


Oh, I know a LOT of people like that. (myself included with my System/32) For many of them though it's the case of the CPU itself takes up a rack or two of space and the rest of the basement is just peripherals. I think the biggest limiting factor for people like that is the cost of real estate these days, plus if you live with anyone else, like a wife. ;)
 
Last edited:
I knew a fellow who had a PDP 11/70 in his garage, complete with peripherals. Not terribly huge and still very mainframe-looking. Best is that a lot of those were built, so not horribly uncommon.
 
Another option might be a small VAX, say an 11/730 or 11/750. Still pretty mainframe-looking.

Do be aware that these old systems do drink a fair amount of lightning-juice, so take that into account. At least you won't have to install a chilled water supply or MG sets.

Biggest question: Are you married? If so, would your wife entertain the competition?
 
On the CDC 6000/Cyber mainframes, they were left on 24/7. Powering down and then back up usually entailed a few hours of CE time. The really big old mainframes did not like to have their power cycled. On the other hand, that meant that I could schedule hours of block time in the dead of night or on weekends and have unfettered access. It was very convenient because I was involved in OS programming and trying to beg an hour or so during normal business hours to run your own deadstart tape was pretty difficult. It was a regular thing for me to end my workday with the 9 AM status meeting.
 
I maintained the OS on a Honeywell 6000 series mainframe in the late 70's. The machine was not used from 6:00 PM Sunday until 3:00 AM Monday, but was left powered on so it would not temperature cycle. I used that time to test new OS versions. It was easy to boot an test a new OS myself.
 
Chuck(G) said:
Another option might be a small VAX, say an 11/730 or 11/750. Still pretty mainframe-looking.
Click to expand...
Yea, but the PDPs have all the blinkenlightens and flippinswitches. VAXes look like washing machines without the dials. 1401s look like a chest freezer (at least the ones I've seen). Anything with a visible reel-to-reel tape drive will look like a mainframe, even it's it's interfaced to a Z80.

The best, modern, illegitimate thing is that PDP-11 kit that interfaces to a Raspberry PI running SimH. Very impressive, low power, can keep it in the house along with the wife.
 
Well, CDC big iron as well as Cray didn't have lots of blinkenlights (any?) or flippenswitches either. Cray was a visionary, way ahead of his time.
 
Chuck(G) said:
Well, CDC big iron as well as Cray didn't have lots of blinkenlights (any?) or flippenswitches either. Cray was a visionary, way ahead of his time.
Click to expand...
Oh the CDC CYBER and 6000 series had a deadstart panel with plenty of switches. The deadstart panel switch settings were the equivalent of a boot ROM.
While these machines had not many visible blinkenlights (the CYBER 170 series machines had many status LEDs behind the doors which were normally shut), but they had something much better. They had the DD60 or CC545 consoles which provided much more information and control than blinkenlights and switches ever could.
 
I don't think it would make sense to run a real mainframe at your home (unless your are a billionaire), but you could run an emulator. For IBM 370 and later that would be Hercules and for CDC 6000 or CYBER series that would be Desktop CYBER. There are several other mainframe emulators I am not too familiar with.
 
thunter0512 said:
Oh the CDC CYBER and 6000 series had a deadstart panel with plenty of switches. The deadstart panel switch settings were the equivalent of a boot ROM.
Click to expand...
You don't have to tell me--I worked at CDC SVLOPS SSD for several years developing software that the world is blissfully unaware of. I left just before the 170s made their appearance--at that time, I was on the STAR-100 project. We had a whole MCU with a drum memory (like the 7600) to start the system--no blinkenlights or switches.

The DS panel was nowhere near the operator's console in any case.

I've tried the Desktop Cyber and it's not that good. Try deadstarting SCOPE 3.1 and bring up DIS on a control point. It doesn't work. I wonder how well MACE would come up...
 
Tried on my (Linux) system, didn't get anywhere. Did an AUTO. after deadstart and then 3,.DIS Nothing

Ah, forgot the period after 3.DIS. Too used to SCOPE 3.4 console entry with autocomplete. However, if I shutdown and deadstart a second time, x.DIS. drops with a "JOB FILE READING ERROR ON 1BJ". If I omit the AUTO. entry, it comes up fine. Any clues?

You don't happen to know the whereabouts of a 3.3 or 3.4 deadstart tape, do you?
 
Last edited:
As I wrote, maybe it is an operator problem. The SCOPE 3.1 manual will shed some light on how to properly use SCOPE 3.1. Regardless, user trouble with guest operating systems has nothing to do with the quality of the hardware emulation in Desktop CYBER.
 
Picked up the 3.0 Operator's Manual off of bitsavers. Slim, with not a lot of information.

Could be that a lot of this is slipping through my wetware, as my experience was almost 50 years ago--and that was with very unconventional system software. We had just enough support for SCOPE to run builds--the CMTR and many PPs were our own code. We'd occasionally get someone from CPD who would ask if they could run a job--and then often give up out of frustration because of the incompatibilities. No permanent files, no 6RM, etc.

It might be fun if an old Zodiac deadstart tape showed up.

By 1974, I was on STAR and by 1977, I was deep into microprocessor work.
 
Chuck(G) said:
You don't happen to know the whereabouts of a 3.3 or 3.4 deadstart tape, do you?
Click to expand...
No, but there are some NOS/BE deadstart tapes which would be the closest thing to SCOPE 3.4.

Of course NOS and NOS 2 are the OSs the majority of sites ran. They were easier to use, operate and customise to your particular hardware configuration.
SCOPE and NOS/BE were less user friendly.
 
You must log in or register to reply here.
Back
Top