Impact Printers – CompTIA A+ 220-1001 – 3.11


Dot-matrix printers continue to be used for those niches where laser, inkjet, and thermal printers simply won’t work. In this video, you’ll learn about dot-matrix print heads, printer ribbons, and tractor feeds.

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An impact printer is a type of printer that is making an impact on the page to be able to create the output. One of the most common consumer impact printers is the dot-matrix printer. The dot-matrix printer has a series of pins on the print head that are pushing through a ribbon and impacting the page to make these letters and characters. Because there is a physical pin that is pushing onto the page, this is a good printer to use if you’re looking for something that uses carbon or carbonless forms to make multiple copies at one time.

This is also a relatively low cost of printing and doesn’t take much power. There’s no heat involved. You’re simply pushing a pin and hitting a page of paper. Because of this impacting process of the pen hitting the paper, this tends to be a very noisy printer to. Use this would not be a good printer to use in a library or anywhere else where you didn’t want to make a lot of noise with the printing process.

You can also see from this output that this is not the highest resolution output. This is very commonly used for numbers, letters, and characters, and not commonly used for images or graphics. But you’ll still find dot-matrix printers used at airports, car rentals, or places where multiple copies need to be made in a single pass.

We call this a dot-matrix printer because the printer head itself has a matrix of pins that are being used to form these letters and characters on the page. This print head is going to move back and forth across the page, and as it’s moving, those pins will push into the paper to create the character or the letter on the page.

There’s only one single matrix on this print head, so the print head has to move all the way across the page and back again to be able to create the output.

Here’s a close up of the entire head. The small pins are behind the print head. There is a ribbon in front of those pins, and there is paper behind it. So as the pins push through the ribbon, they create the output on the page.

Here’s a view of this matrix of pins from the paper side. These are the pins that are pushing out of the print head and creating the output. This is a 24 pin matrix of pins. There are other nine pin dot-matrix printers that are common, as well.

The ribbon itself is usually this modular case that contains one very long ribbon, and you send the ribbon through multiple times until you get to a point where the ribbon itself has lost enough ink that it’s difficult to read the output on the page. But because this is a modular ribbon, it’s very easy to pop it out of the printer and pop a new one in and have a fresh ribbon ready to go.

The size and style of these ribbons varies greatly between the different printer versions. So if you are replacing this ribbon, you want to get exactly the same ribbon type that matches the model of the printer that you’re using.

It doesn’t look like the ribbon would be that long, but inside this ribbon cartridge, you’re compressing down the ribbon into these smaller areas. So the only ribbon that you’re seeing is on the front as it’s passing through, and then going back into this compressed part of the cartridge.

With laser printers or inkjet printers, we’re usually using paper that is in single sheets and one page is printed after another. With a dot-matrix printer, you tend to have these continuous sheets of paper that are one very long piece of paper with perforations in the middle so that you can separate them.

To be able to feed this paper through the printer, you’ll often find that this continuous form has these small holes on the side of it. This is called a tractor feed, and it uses these holes to be able to pull the paper through the printer. This means that you have to be sure that the holes on the paper are lining up perfectly with the tractor feed that’s on the printer. If they’re not, you’ll find that the paper is not feeding properly through as you’re trying to print out a page.

Here’s a view of the tractor feeder that’s on the printer that is pulling the paper through using these holes. You’ll notice this paper has perforations so that you can separate the tractor feed holes from the paper once you finish printing. This means if you’re buying new paper, you want to be sure to get paper that has these tractor feed holes so that you’re able to use them on your dot-matrix printer.

And usually when you’re buying paper, you have the option to purchase paper that has the perforations so you can remove the tractor feed, or it might be paper that doesn’t have perforations. This one, obviously, you can’t remove those holes. This is what we call green bar paper because of the green bars that go across, and once you finish the print out those holes will always be part of that paper.