Epson LX-86TM Figure 3-l.A capital T, Chapter, Elements of Dot Matrix Printing, The Print Head

Chapter 3

Elements of Dot Matrix Printing

This chapter is for those of you who want to know something about how your printer works. It’s a simple, non-technical explanation of the basics of dot matrix printing that will help you understand some of the later chapters.

The Print Head

The IX-86uses a print head with nine pins or wires mounted vertically. Each time a pin is fired, it strikes the inked ribbon and presses it against the paper to produce a dot. This dot is about 1/72nd of an inch in diameter. The size varies slightly depending upon the age of the ribbon and the type of paper used. As the head moves horizontally across the page, these pins are fired time after time in different patterns to produce letters, numbers, symbols, or graphics.

For example, to print a pica capital T, the head fires the top pin, moves 1/60th of an inch, fires the top pin again, moves 1/60th of an inch, fires the top seven pins, moves 1/60th of an inch, fires the top pin, moves another 1/60th of an inch, and fires the top pin once more to finish the letter.

Figure 3-l. A capital T

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