PC Maintenance Class 16

This is the class we missed....we'll have a catchup class tagged on at the end of the term before Easter!

PC Maintenance Class 15

Tonight's class was a hardware practical session.  For the first time ever in PC Maintenance, our first midi-tower shaped PC. The group had quite a good session at dismantling the computer and reassembling it.


Here are a selection of pictures from the session:

PC Maintenance Class 14

Printers....printers.....printers....hard to sometimes live without, and often the bane of our lives! Tonight's class was all about the different types of printers there are, troubleshooting them, and setting up a wireless printer.


The five types of printer we discussed were:

• Laser Printer
• Inkjet Printer
• Dot Matrix
• Thermal Printer
• Plotters

For a detailed description, click on each of the headings above.

There are lots of different types of printer on the market, with markedly different prices, print speeds and features. You probably have a rough idea of what it is you’re after, but there’s no point paying for capabilities you will never need. 


Start with a list of basic requirements and prioritise those. Is it more important to be able to have the option of producing colour output, or do you need to keep costs down and print speeds up?


How to choose a printer: Colour or straightforward monochrome?


If you usually need to print text documents such as letters and reports, a mono laser printer will best suit your needs as it offers the crispest text output and the best combination of fast page-per-minute output and low ink costs.


If, however, you occasionally need to print in colour, choose an inkjet printer with a strong emphasis on detailed text output. If colour is the main thing and you’re going to be pintoung out lots of photos or artwork, a dedicated photo printer with individual cartridges for each colour (rather than a single combined colour cartridge) is what you need. For fine skintone nuances and other subtle shading effects, a six-colour printer with a light cyan and magenta and a rich black ink should produce better results.


How to choose a printer: Printer types


For everyday printing duties, you’ll want an A4 printer. A3 printers are considerably more expensive and for all but art departments and creative teams, it’s generally more cost-effective to outsource print jobs involving larger paper sizes.

Inkjet printers used to offer only mediocre text reproduction, but the technology that places the tiny drops on ink on the page is now so refined that you’ll be hard pushed to distinguish between a laser-printed document and one produced by an inkjet printer. Instead, the trade-off now is between the greater number of features and the luxury of colour printing versus the raw print speed and lower cost per page of a colour laser printers.


Confusingly, there are now some very good value colour laser printers on the market too, though for home users rather than offices, a multifunction printer or photo inkjet model will probably be the best bet. Most, but not all, will have an adjustable paper tray that helps you align 6x4in and 7x5in photo printing paper.


Variously known as multifunction devices (MFDs), multifunction printers (MFPs) or all-in-one printers, the biggest slice of the consumer photo printer market is accounted for by these combined printers, photocopiers and scanners. As with dedicated photo printers, you’ll pay a bit more but get better results from an MFD that has six separate ink tanks than one with combined colour cartridges.


Unless you’re really in the market for a multi-function device, focus on the printer’s attributes (as this will get the most use) and treat the scanner and photo copying features as a bonus. They are, however, useful for archiving and for scanning in and digitising documents that can then be edited, as well, of course, as for making copies of photos that were originally taken on a film or slide camera.


Wireless and PictBridge features are useful on all types of printer. The latter allows you to take photos straight from a digital camera and print them out. However, many printers and MFDs now have media card slots (SD Card, MMC, xD Picture Card and so on) and USB ports so images can be read from external sources. A Wi-Fi connection will enable you to position the printer almost anywhere and have laptops and PCs to it without needing to be physically connected to the device.


How to choose a printer: Office printers


In an office environment you’ll want Ethernet connectivity so several computers on the network can access the same printer. If you’re an office administrator with responsibility for controlling print costs, PIN code access and the ability to determine who can use the colour features will also be important. An administrator interface will allow you to do this, though some printers also have some access functions on the device itself.

Yellow network cable plugged into the back of a laser printer.

If you’re choosing an office printer, as well as the print speeds and cost per page calculations, it’s likely you’ll need to factor in the cost of replacement toner drums (for a laser printer) as the higher use means this expensive part will wear out more quickly. You can generally save money by sending back expired cartridges and, sometimes, old drums, to the manufacturer when ordering replacement consumables.


In an office environment a printer that can produce 30ppm (pages per minute) of mono text documents should suffice, though higher up the price chain you’ll find models that can print even faster than this. You’ll also want a generous paper tray of perhaps 500-sheet capacity. This will save you or other users having to frequently replenish the paper in the printer.  Duplex printing – the ability to print on both sides of the paper – is another desirable feature and will save money on paper. It’s also ‘greener’.


Some office printers have a secondary paper tray that the printer can switch to on demand if the other tray is empty or if you need to print landscape or on a different paper stock.

HP LaserJet with additional paper tray for extra capacity.

The average office workhorse printer of around 25 to 30ppm output and costing in the region of £300 to £400 should offer all the above, though you may need to pay a little more for duplex printing and additional, more capacious paper trays.


As with desktop printers - ones that connect directly to the laptop or PC from which you’re printing – you may decide a combined printer, scanning and copier is a more cost-effective option for your small office network. As well as Ethernet and, possibly, Wi-Fi, you may want to consider fax capabilities on top.


How to choose a printer: Colour control


Regardless of whether you’re buying a laser or an inkjet printer, or whether you’re buying for home or business use, you’ll want to be able to control colour printing costs. With several inks needing to be replenished and far more ink being laid down on each page than on a plain text document, printing in colour can soon get very expensive indeed.


Ideally, you’ll want the ability to switch off the colour ink tanks when you’re only printing draft documents or plain text ones, since in the long run this will be better value. Most printers – particularly ‘photo’ printers – will create a rich black from using some colour ink as well as black.


Some inkjet printers have a black ink tank and a combined one for the three colour inks cyan, yellow and magenta that are used. When one of these colour inks is depleted, you’ll have to replace all three ink tanks – wasteful and expensive. However, if you rarely print in colour anyway and are buying a cheap printer, you may not mind this. As an aside, unused ink sitting at the bottom of a cartridge soon shows its age and may clog up the printhead nozzles. Some brands of ink specifically state that they have anti-coagulants to prevent this, but as usual, it’s the more expensive ones that tend to offer this.


How to choose a printer: Print quality


Printer resolutions are expressed in dpi – dots per inch or, occasionally, lpi (lines per inch). A print resolution of 1200x1600dpi is about standard, but some printer manufacturers claim much higher print resolutions. Often, these higher figures will denote ‘interpolated’ resolutions that are governed by software. For a fair comparison of hardware capabilities and image quality, ensure you’re looking at the non-interpolated specification. For draft document printing, a resolution of 600x600dpi is fairly standard. You don’t need to print in ‘best’ or ‘fine’ print mode unless you’re producing a finished document that needs to look as good as possible; use draft or quick print mode wherever possible to save on ink.


In general, a more generous onboard memory cache on the printer will enable it to handle larger image files, but there’s no point trying to print out an incredibly detailed image on a printer than isn’t designed to do so. The printer may well grind to a halt under the strain and you’ll waste expensive photo paper and ink.


How to choose a printer: Ink costs


When choosing a printer, the cost of replacement inks is likely to be one of your biggest considerations.  This aspect is so important it’s usually quoted as part of the TCO (total cost of ownership) when buying a printer for business purposes. Be cautious of the figures used to come up with this figure. High yield ink cartridges can help keep costs down, as can separate inks for individual colours since you don’t need to replace all the colours just because you’ve run out of blue (cyan). However, calculating ink costs and TCO based on these higher yield cartridges is a popular ruse with printer manufacturers too.

When calculating ink costs you need add together the costs of all the inks involved and then divide the figure by the number of pages that can be printed. Since most printing involves text and a smattering of image such as logos, very few pages you produce will be completely covered in ink. As a result, the ISO standard measure that printer manufacturers use to calculate the page yields they cite for their printers are based on an average 15 percent page coverage. If you’ve ever printed out a full-page photo and wondered why the printer soon starts flashing a warning that its ink tanks are empty, it’s almost certainly down to gap between your expectation of being able to print photo after photo and the letter of the law when expressing page yields for ink cartridges.


If photo printing is your main priority, look out for figures exclusively based on full page coverage and this sort of printing and choose a photo printer that comes with the special photo inks we described earlier.


Note, however, that printer manufacturers invest an awful lot of money in creating inks that will show off your photos to the best advantage – and don’t take kindly to customers trying to use cheaper, ‘non-branded’ inks in their printers. Should your printer go wrong, they may cite a warranty invalid clause. It’s usually cheaper to shrug your shoulders and buy a new printer than to shell out for a printer repair yourself. Don’t get stung by buying a cheap new model that will cost a lot to keep in ink though.