This wiki is part of a series of Manuals For Computer Refurbishers.
Monitors - CRT and LCD ¶
- The two most common types of monitors are CRT (Cathode Ray Tube) and LCD (Liquid Crystal Display).
- CRT is most common at this time although more LCD monitors are coming. Some LCD monitors require a separate power adapter. The power adapters are specific for each model. Try to keep them with the monitor if possible.
- The first step in working with monitors is the same as working with computers: triage to sort those to be kept from those to be repaired or recycled.
￼￼￼Initial sorting – Reuse or recycle? ¶
- Monitors contain hazardous materials and need to be handled carefully. CRT monitors contain lead that would be toxic if leaked into the groundwater supply. If the glass is broken in the CRT monitor, sweep the contents into a sealed container, be careful not to breathe the dust.
- LCD monitors contain mercury. If broken, handle with gloves.
Damaged connectors can make the monitor hard to test.
- For the purposes of refurbishing we do not advise removing the plastic case of the CRT monitor. The stored electrical charge in the capacitor can be dangerous. The vacuum tube in the monitor can implode if the glass is cracked and air rushes in. Glass can fly everywhere. Please handle carefully. Another section will cover the proper way to demanufacture monitors.
- Sort out monitors that are beyond testing such as:
- Scratched screens
- Burned in Screens
- Badly discolored or damaged cases
- Bent pins on the video cable
- Damaged video cables that can’t be repaired
￼Screen test ¶
- ￼￼This is a good, free test screen that can be downloaded from Computers for Classrooms under Tech Tips.
- It works very well if you have the image set up on another monitor so you can compare.
- Use the adjustment on the monitor to center the picture and margins, adjust the color and hue and check out problems. Many monitors fail because the screen is too dark. That is an indication that the monitor is failing.
- Monitors can be hot swapped, no need to turn off the computer when plugging in the video cable.
Comparing screens ¶
- ￼￼￼It helps to have a good monitor set up to use as a comparison. As the monitors age they often become darker. By having the comparison monitor it is easier to see variations in color and brightness.
- The adjustments on the monitor are used to align the picture and center it on the screen. If the controls cannot correct the image, the monitor should be set aside for recycling.
Handling monitors to be recycled ¶
- What will you do with your rejected monitors?
- Monitors may be [[Demanufacturing_for_Refurbishers#Section_Demanufacturing_monitors_and_televisions|demanufactured] or recycled.
- Before you accept monitors, decide how you will get rid of those that are defective.
- Many refurbishers have recyclers that will take all of their discarded electronics for demanufacturing, disassembling electronics for their scrap value.
- Decide with your recycler how to handle your discards.
- One method is to cut the power cords to make handling easier. There is a scrap value for the cords and handling monitors is much easier without cords dangling down to trip over.
- Monitors can be palletized for easy delivery to the recycler. See our unit on warehouse operations.
Other monitor issues ¶
- Monitors can appear to have missing colors if the video cable is crimped or bent. Be sure the video cable is straight when testing the monitor.
- Monitors may need to be degaussed. If the monitor has come close to a magnetic field, the colors may become distorted. Many modern monitors have a built in degaussing function that can be found along with the other adjustment features accessed from the front of the monitor. This is not as common of a problem with modern monitors.
- Some refurbishers have purchased an inexpensive kit to turn the monitor into a television set. There is a market for very low-cost television sets more typically in third world countries.
- Some businesses repair monitors as many monitors have a defective circuit board. We will not get into monitor repairs that include removing the case. Each monitor has a transformer and a powerful capacitor that can contain 35,000 volts of power. The vacuum tube is fragile, and risks breaking, causing an explosion of leaded glass. Additional training should be received before handling dangerous equipment. That is beyond the scope of this wiki.
￼￼￼Printers – ink jet ¶
- Ink jet printers are often difficult to refurbish. The cost of new printers is often negligible when pricing the cost of the ink alone. Older printers often suffer from having dried ink clogging the heads. The costs of time to soak and clean the heads, replace the ink cartridges and test the computer are often not cost effective. Some high-end ink jet printers such as office all-in-one units that have high-capacity ink cartridges, and can fax, scan, and copy may be worth spending the time to repair.
- Another common problem with printers is that the rubber rollers get dry and cause paper feed problems. Try a product called Rubber Renew.
- The web is a wonderful resource. You can download information from the manufacturer’s web site, find others that have solved a similar problem with the same model printer and find kits available for purchase if the printer is worth it.
￼Laser printers ¶
- Laser printers are popular, as the cost of the toner is much less than the cost of inks.
- Plug in the laser printer and try to print a test page. If you look up the model on the Internet you can find the keys to press to get the diagnostics on the printer. Generally, you just press the main button before turning on the printer and hold it down until you see a blinking light. You will be able to find the total number of pages that have been printed as well as important information about the age, and wear the printer has sustained, as well as the remaining amount of toner and drum life.
Look for a jet direct network card or hard drive.
- Many of the older laser printers are real workhorses and can have a very long life. The cartridges in the older printers often hold more toner and are more economical to run.
- Look for jet direct network cards as they are easily removed and transferred to another similar laser printer. Next to the jet direct card may be a hard drive. Be certain to remove the hard drive and wipe it as a security measure.
- The jet direct card may need to be reset. Generally, this is done by doing a “cold boot” of the printer that changes back to the default settings when the printer was new. You can follow the menu on the printer or browse the web for the printer manual for directions.
- Laser printers may also have feed problems similar to ink jet printers. You can try Rubber Renew on the rollers or look online for a kit to solve the problem.
Save the USB printer cables ¶
- Most printers have a USB printer cable with it. The cables often sell for $10.00 to $15.00 dollars when new. They can easily be reused.
- Refurbishing printers is a topic beyond this wiki. Many printers are usable with cleaning and possibly replacing the toner cartridges and the drum. If the print is blurred during the initial test the problem may be the toner cartridge. Some donors have purchased used cartridges that may not be of the best quality. Some problems disappear after using full, good quality cartridges.
- It is a good idea to check out the make and model on the Internet to see if other owners have had a good experience with a particular model, or if it the printer is known to have problems.