Identifying Electronic Components

Being green is all the rage these days. It’s possible to be very involved in the world of electronics and to still be green. Part of that effort involves recycling, which can be done on your own with the right tools and the right information.

You’ll need some very basic tools to recycle most electronic devices. These include a soldering gun to remove the components from a circuit board, if necessary. You’ll also want various types of part pullers, which are specifically designed to remove certain types of parts from electronic devices. Of course, you’ll also want to know what you’re looking at when you’re hunting for something that might be recyclable and this information will help you to get that knowledge.

What is Considered Electronic Trash?

Old computers, blown-out stereo tuners, old video cards, radios that are far past their useful lifespan, and more all constitute examples of electronic trash. Electronic trash is actually a serious issue today. There are so many new devices being introduced onto the market every single year that it’s inevitable that there is going to be a lot of waste at the other end of the consumer use cycle. That trash sometimes contains pollutants and chemicals that can become serious environmental issues and serious health issues, as well.

Electronic waste also includes peripheral devices. Monitors, for instance, are electronic waste and, with the advent of flat-screen computers, there are certainly a lot of CRT monitors in the landfills these days. Printers, external hard drives, and other external devices are also forms of electronic waste.

Some nations actively recycle these forms of waste and others do not. There are good reasons to give electronic waste a second look if you live in a location where it is not recycled immediately, as you might be able to recycle a lot of what’s on those circuit boards yourself.

Which Parts of Malfunctioned Boards can be Reused?

For the purposes of salvage, you can break everything on a motherboard down into two categories: removable and non-removable. Essentially, anything that you can remove from a motherboard with a soldering gun or by other means can be reused, provided that it still functions.

There are other devices that have components that you can reuse. For instance, an old refrigerator may have some microcontrollers on it that can be removed and reprogrammed for different purposes. An old monitor may have high-voltage components that can be reused.

There are more obvious items that can be recycled, of course. A computer that is discarded with its hard drive, video card, and other cards installed can be a gold mine as far as salvage goes. Getting parts off of the board, however, is likely to be what most real enthusiasts will be interested in. There are oftentimes magnets on discarded electronics that can be useful, as well. Check speaker systems for those. Old power supplies have transformers, fans, and other components that are easily reused.

What’s important to keep in mind is that some of the components may actually still have a charge. This is particularly true of capacitors. If you are getting into recycling devices that carry a great deal of power—CRT monitors, for instance—be sure you’re aware of any safety issues that apply and that you know how to deal with them. Not doing so could result in serious shocks. The amount of power stored in the components of a CRT monitor can kill a person if they are discharged accidentally. Be sure you’re safe before you salvage!

How to Reuse Electronic Components?

Electronic components can be reused in many different ways. If you’re disordering capacitors off of a circuit board, for instance, they could simply be soldered into a circuit board that is in need of a component of the same specifications. Sockets, resistors, transistors, and other components may also be reused in the same fashion.

Some components really require no more than detaching mounting screws and disconnecting a power supply to be reused. For instance, case fans that are oftentimes tossed out with an old computer can be detached and reused quite easily, without any real modification or testing at all. If they work, they work.

Before you reuse any electronic component, be sure you do the following:

  • Test the component to make sure it’s still working
  • Verify the specifications of the component—voltage, amperage, etc.
  • Clean the component using an appropriate method

Which Electronic Component is Which?

The easiest way to identify the component you want is to look for an exact match on a motherboard or other electronic device and disorder it. You do have to know what you’re looking at, however, and this information will help you to figure out what’s in front of you when you’re ready to start salvaging.

Batteries are easy to identify. On a computer motherboard, they are usually the flat, circular batteries that are oftentimes used in watches, though they may be much larger in size than those batteries. These can be pulled, tested, and reinstalled in another device, provide the model of the battery is an exact match. Most batteries on motherboards can be removed without using any specialized tools at all.

A bridge rectifier will usually be a square or rectangular component with several pins that are soldered into the board. They are oftentimes marked with the letters “BR” to more easily identify them.

Capacitors will usually have a C on them to identify them. They do come in many different designs, however, so sometimes you have to double-check to be sure.

Capacitors are oftentimes cylindrical devices that look something like a small soda can. They typically have two leads that are connected to the motherboard or other board via solder joint. They have specifications printed on them to let the user know their exact working parameters.

Capacitors vary tremendously in size. The smallest are smaller than a fingernail and the largest can be almost as big as a 12oz beverage can.

CAUTION: Capacitors can remain in a charged state on a discarded electrical appliance. Particularly if you’re working with a capacitor that holds a significant charge—such as in the back of a television or monitor—your need to discharge the device before handling it. Have someone train you to do so before you remove any large capacitors.

Crystals are usually pretty easy to spot. They’ll be marked with an operating frequency and are oftentimes protected by a metal case. Look for the letters X or Y on these devices to identify them. These can also be pulled out of old radios and reused. They may vary tremendously in size.

Diodes look very much like resistors in many cases. They are usually differentiated by having the letter D printed on them, however. They also come in designs that are square, rather than having the classic resistor look. Diodes and resistors use different color coding schemes, which also provide an easy way to identify these devices.

Fuses are typically not at all hard to identify. Some of them have clear glass cylinders so that their state can be assessed visually. Be sure they’re not blown before you pull them.

Fuses will have an amperage (A) and voltage (V) rating on the side of them to identify their operating capacity. These markings are easy to spot and serve as a handy way to identify a fuse.

Inductors are usually not hard to spot, but it can be hard to figure out their specifications. There is a color coding system that can be used to identify their operating specifications, which may be helpful if they are color-coded. They are identified by the marking “L” on the device. They may need to be tested once they are harvested to identify their inductance.

These appear as what most people call “chips”. They are usually rectangular devices that have several different pins that are used to affix them to the board. They will have either IC or U on them, in most cases.

The outside of these devices is not a reliable way to determine their function. The easiest way to do this is to check the manufacturer site, look up the appropriate device and get all the information about it from there. The literature for these devices also tends to have suggested applications, so it’s good to find the right literature for any IC that you pull.

Oscillator is another word for crystals. See the information above on crystals to learn how to identify these devices on a motherboard.

Potentiometers are oftentimes directly accessible through the case of a device, such as by the knob on a volume control. These are variable resistors and they’ll have their specifications written on the outside of the device.

These devices typically have the letters VR stamped on them, making them easy to spot.

Relays may look like an integrated circuit or another component at first glance. Most of them are contained in a plastic housing. Look on the housing for the letter K. This indicates that the part you’re looking at is a relay.

You’ll find resistors all over circuit boards. These typically have colored stripes on them that serve as a color code indicating their resistance in ohms. They sometimes have the ohms printed right on the side, as well, however.

These devices may look something like a capacitor in some cases, so be sure you check the device before you remove it. It should have an R printed on it.

Transformers are usually a bit larger than other electronic components, though this is not always the case. They are easy to spot and will have a T written on or near them. They are most often found in power supplies, where they are easily removed and repurposed. These devices are very durable and make great candidates for your salvage operation.

Transistors generally sit at an elevation off of the board and have three connectors. They are marked with a Q. These devices are easy to remove and very versatile, so they should be harvested whenever the opportunity presents itself.

What is Electrostatic Discharge (ESD) Protection and How is Relevant for Reusing Electronic Components?

Electrostatic discharge happens when a component is shorted out and electricity flows across or through the device. It can happen because of induction, static electricity or, in the case of capacitors, because the device is charged and was not discharged before it was removed and the contacts were somehow bridged.

Usually, ESD makes quite a spark, so it’s easy enough to know when it happens. This is not always the case, however.

ESD needs to be considered when salvaging electronic components. Most electronic components can be destroyed by such a discharge. This is why computer techs take measures to ensure that their bodies don’t have any static build up when they touch the components inside a machine. One static discharge into a processor and it’s fried for good!

You can use a mat to insulate yourself so that you don’t build up a charge to avoid this. You can also use a strap to ensure that there is an alternate path to ground for any static you may have. Most techs will also touch a metal portion of the computer they’re working on before touching anything inside.

Remember that a motherboard, even if it’s been unplugged for a while, may still be carrying a charge. Be sure you don’t drop screwdrivers or other tools on it while you’re working, as such a device may short out the components and cause an ESD.

There is a greater hazard of having an ESD in conditions that are very dry, particularly if the device is being worked on in a room with a carpeted floor. Take the extra time to discharge any static on your body and use a strap to ensure that you’re not building up any more and you shouldn’t have trouble with this.


  1. I’m not sure where you’re getting your info, but great topic. I needs to spend some time learning more or understanding more.
    Thanks for fantastic info I was looking for this info for my mission.

Leave a comment

Your email address will not be published. Required fields are marked *