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In the beginning was the computer room at Markham District High School, in Markham Ontario Canada. MDHS was the only school in the area that had a computer. It was an IBM 1130 with 8k of core memory. We're talking magnetic ferrite cores. I have pictures somewhere. There was a 2501 card reader off to the right side, and a 1132 line printer on the left. Each unit was about 4' high by 3-4' in width and about 2' in depth. This was serious machinery for the day... 1969. The machine had just been installed the summer before I started Grade 9 in September 1969. Being a geek (although that term wasn't a positive one back then!) I couldn't think of any place I'd rather be in that school, except maybe the Math office (which was just down the hall, so no great hardship to move between them.)
A group of about 6 gradually formed around that amazing machine. We eventually formed the Wednesday Night Computer Club, with the privilege of playing with the 1130 on Wednesday evenings. We were unsupervised, and used our time mainly to disassemble the computer, take pictures of the parts, reassemble it, and do otherwise crazy things we shouldn't have been doing. I'm amazed it never came back to bite us. We did some programming as well. The 1130 ran Assembler and Fortran. Yes, Fortran in 8k! At one point, we managed to partition the memory and run 2 processes, and Fortran ran even on the remaining 4k.
One of my programming projects was to figure out a way of speeding up the card reader. Reading cards in a Fortran program would take about 1 second per card. We knew that the physical limits were much higher, so I wrote an Assembler program to read the cards at maximum physical speed into a memory buffer. It whirred right along, at least 10 times faster. We used this trick in the most practical manner we could think of. We moved the card reader near the window, opened the window, and shot cards into the yard at about 10 cards per second. Very practical. It was the only time we got close to being shut down, when we had to explain why the yard was full of computer cards the next morning. Someone obviously dropped a box of them! That really did happen on occasion, which would lead to much bad language and many hours of manual sorting. Unless the programmer had remembered to punch sequence numbers into the cards, in which case we could use our sorter. That was another massive machine, about 4' high and 8' long. It didn't do a very good job and was seldom used.
Programming could be done 2 ways. The control console had a series of toggle switches and corresponding lights. You could flip the switches to a sequence representing a binary word, hit Enter on the keyboard to store that number, and move on to the next line. It was very tedious, and we only used that approach to load the boot program when we managed to corrupt the hard drive. That hard drive was in a removable cartridge, about 2' in diameter. I think it had a capacity of about 1MB. The other way to enter programs was of course via punched cards. These were the traditional 80-column cards. Each card contained a single line of code, usually Fortran. They were punched on a separate keypunch. There was no "undo", so accuracy of typing was critical. I still watch my fingers on the keyboard.
Another trick we found was to create a program with variable-length loops chained together. This would cause the CPU to emit an RF signal of varying frequency, that you could pick up on an AM radio. It was a primitive form of "computer music".
I understand that the 1130 was still in residence, although not used, until some time in the 90s. I hope it went to a good home.
You can learn more about the 1130 at http://ibm1130.org
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