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Litton - Monroe

37 years for Monroe Company, from adding machines to computers, by Bob Heptig:
Thinking back on the 37 years I worked for Monroe Company is a bit difficult now as there are so many memories that have been lost. Basically I remember that I was an auto mechanic and not to happy about doing that for the rest of my life so when a couple of ham radio operators that had been working for Monroe, the calculator Company, asked me to put in an application in for a service technician opening. After several tries over a period of 3 years, they finally accepted my application in the year 1962.

I went right to work learning how to repair adding machines, bookkeeping machines and calculators. At that time I didn't even know what a calculator was nor had I ever seen one before. Not only did I have to learn to repair the current models being produce which of course used an electric motor to make them work, but also had to service pre-WWI crank operated machines some of which were still running since the Founders, Monroe and Baldwin started the company in 1917. To management's delight and to my own as well, I found my niche and told myself I will retire with this company some day.

It seems like a whirl wind now but I quickly went to many schools to learn repair on the Monroe products. The schools were held in various cites scattered through out the U.S, between New York and Los Angeles California. Schools lasted 1 or 2 weeks and up to 3 months at a time. As time went buy, and in the 70's as I remember, a new unimaginable calculator was introduced. It did all the things the old mechanical calculators did except it had no moving parts except for the key's on the keyboard going up and down. This used a light bulb like glass tube, with filaments that resembled the numbers 1 through 0 in it. It was called a nixie tube display. There were 8 or 10, inch long and 4 inch high circuit boards lined up in a row like grave markers in a cemetery. They were plugged into something they called a "Mother Board" There was no such thing as double sided circuit board in those days and the memory was made up of two of these plug in circuit board which had little donut shaped magnets with a coil of wire wrapped around it. These little donuts held the calculations so were called the memory. An interesting thing about them is that you could shut the calculator off at night and the figures were still there in the morning when you turned the machine back on.

Later technology developed a new thing called an integrated circuit. Now I had to learn a bunch of new little centipede looking things called "integrated circuit". Inside them were "and gates, NAND gates, NOR and OR gates and flip flops". Amazing little things that properly used would take the place of transistors, resistors and many other electronic components used in the early machines. This enabled the new smaller versions of the calculator. Now they have developed double sided circuit boards but didn't have the technology to get the voltage and signals from one side of the board to the other. So they used what they called a "feed through pin" which was a small wire that soldered on one side then turned over and soldered on the other. A few months on the market and the trouble began. It seems that when the machine warmed up to the normal operating temperature, the feed through pins expanded and contracted at a different rate then the circuit boards did, thereby causing a momentary bad connection between different feed through pins at different times. Now the service technician, about every six months, had to travel to every calculator sold and remove all the circuit boards to re-solder every connection on them. Needless to say the service man never lacked something to do. Later they developed a means to make double sided circuit boards with plated through holes to connect both sides of the circuit together.

Now the biggest problem became developing a printer that would connect to a calculator and keep up with it and the operator's high speed fingers. Believe it or not some good ten key adding machine operators became so proficient they could add up a long grocery list faster then the printer could print it out. So the next big problem was to correct this by adding memory to the printer so the operator would have to sit back for a few seconds till the printer finished printing out the tape. Later they developed the dot matrix printer that did a pretty fair job of keeping up.

In the 70's Monroe developed an office computer called the "Monroebot" A huge piece of equipment that took up one wall of a good sized office. Thankfully I didn't have to learn or work on that. But from the Monroebot came one of the first desktop computers called the Monroe 8810. It combines an 8 inch orange monitor, the keyboard and motherboard all in one unit. It was determined the orange display was easier on the eyes after a full day behind the computer in an office. The motherboard was on the very bottom of the computer and was loaded with almost every kind of integrated circuit that was available at that time. It also used something called a "delay line" which enabled the data to fall into the correct place while it was circulating throughout all the gates and flip flops. In some cases it acted almost like a screen door spring which delayed the signal as it passed through it. The "Central Processing Unit" (CPU) had not been developed yet but was soon to come. As a result the little centipedes like integrated circuits had to work very hard to handle all that was required of them. A hair dryer and a can of Freon would be used to find intermittent problems in the computer's logic. It could take as long as weeks or months of heating and cooling individual components trying to determine which would quit working properly after it had warmed up or cooled down.

Finally after several years the single chip was developed that would do what used to take a hand full of integrated circuits. And after that came the single chip CPU and modular circuits. and finally the throw away circuit boards. So here I sit with all this knowledge of trouble shooting circuit boards and operating oscilloscopes. The know how of replacing integrated circuits, using tools called soldering iron's and solder suckers and am as obsolete as the old Monroe hand crank adding machine. But that's ok, I don't mind. I feel like I have had a hand in the development of the American electronic era. Wow that sounds important.

Fond memories, by Jennifer Comstock:
This was the first computer my family ever had.  I believe we had one in 1984.  I probably have a couple of pictures of it in the family photo album.
The most interesting thing about this computer was the orange button in the upper left-hand portion of the keyboard.  This button had the ominous word "STOP" printed on it.  No one could tell us exactly what this Stop-button did--they said to *never* push this button.  Apparently, very bad things would happen if it was ever pressed.  So my mom was always very nervous that one of us kids would press this button and break the computer.
One time I was talking to my mom while she was entering customer account info into the system.  I distracted her so badly that she accidentally pushed the Stop-button.  All of the data she'd entered was lost.  She was on the phone crying with tech-support the rest of the day.
I believe now that this was maybe a memory dump.
I remember using the Monroe BASIC interpreter to write my first programs (today I'm a software developer).  It also was my first interaction with Wordstar which I used all the way through high school on various computers.
Fond memories of this computer.  It sat in a corner of my parent's bedroom for years after they upgraded to a new system.  Eventually he gave it away to some very lucky person.

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