Assembly kits – an excellent introduction to the world of electronics

A do-it-yourself kit usually consists of three elements: a project-specific PCB, a set of components and a schematic diagram with a description and instructions. Once soldered and put together, you get a device that performs some (usually simple, but still useful) function. They can also act as a gateway to the fascinating world of electronics.

• Types of kits
• How to choose a kit
• What will you need?

Below, you can read more about the types of devices that can be made in this way. First, however, it is necessary to address the usual comments about such products ‒ because there are two different opinions about ready-prepared electronic kits. One, usually formulated in a rather condescending manner, is that they are “low-quality toys” that “teach nothing” and are actually “a waste of time” (these are genuine judgements collected during a brief search of two large forums dedicated to electrical engineering). Meanwhile, on the other side, there are counter-arguments that show more openness and deeper reflection. Proponents of do-it-yourself kits point out that:

• such products teach you to recognise electronic components;
• the assembly provides the opportunity to acquire information on reading electronic diagrams and symbols used in electronics;
• they provide an excellent chance to learn soldering skills (a ‘feel’ of a soldering iron, how to work with fluxes, plan the order of component assembly, work with precision tools);
• they minimise (but do not fully erase!) the difficulties and failures that come with the first steps in the practice of PCB construction, helping to make the first steps in this difficult hobby.

It is worth pointing out that even professionals who work with electronics on a daily basis often reach for the kits to learn about their design solutions, practice soldering, and sometimes, just for the sheer pleasure of it. In fact, the education and “added value” aspects of such products depend primarily on the attitude of the person assembling the kit.

Types of kits

In the TME catalogue, you can find several types of do-it-yourself kits, varying in complexity and functionality. The two most popular types of such products are classic projects for those just starting out in the electronics field: analogue audio circuits and digital lighting effects. They are manufactured using popular components (e.g. TDAxxxx amplifiers or 555 timer), so that when assembling, the constructor becomes familiar with common parts, how they are powered, how signals are fed in and out, and with all their possibilities.

It is worth bearing in mind that the audio circuits available from the TME catalogue are not limited to amplifiers and preamplifiers, although at the same time it must be stressed that, when compared with the 'ready-made', factory versions, they have an almost unbeatable quality-to-price ratio. What's more, some kits make it possible to manufacture devices that are not so easily available as prefabricated equipment ‒ such as bargraphs, volume unit meters, universal time switches or simple moisture detectors (which can notify, for example, when a washing machine hose leaks). These are the projects which provide you with functional and practical devices, which can be easily put into use in the home or workshop. Applications in the latter include, for example, settable power supplies, testers, probes, generators, etc.

Choosing the kit

The choice of kit can be dictated by either its design features or its functionality.

If the product you are purchasing is intended to serve a primarily educational role, you should take into account its complexity, the type of components used in the circuit, etc. Sometimes a complete amateur should start with a circuit with a very large number of similar components (e.g. LEDs) to be able to practice soldering. Further on, it is good to familiarise oneself with the technique of attaching other THT components, resistors (which also entails deciphering their values), IC bases, etc. What’s more, at this stage already, the “apprentice” will come across the issue of the polarity of components, i.e. the fact that they must be placed in the correct orientation. It is also important to know the optimal order in which to place the components on the laminate, so that you can work comfortably. All that information and reflexes are completely obvious, even instinctive, to the professional, however, they can only be acquired through personal experience.

As for the use of the product: if you order a kit primarily because of the function it can perform, and at the same time you are not skilled in assembling electronic circuits ‒ you must realise that some of the kits from suppliers such as Velleman or Nord Elektronik, are complex designs equipped with a number of integrated circuits, not the easiest to assemble, and even less so to troubleshoot, when a malfunction occurs or manufacturing defects become apparent.

Of course, there is another key point that cannot be overlooked: do-it-yourself kits are admittedly ready-prepared sets of parts, but their manufacturers assume that the constructor has the basic equipment and consumables, i.e. soldering iron, solder, cleaners for the circuit that is being constructed etc. In this context, a few other details that may escape the attention of amateurs should be clarified.

Don’t overlook the details

To avoid disappointment, it is always necessary to take into account the additional cost of getting the kit up and running, and especially its regular use. Most kits are supplied without a dedicated housing, it’s just the circuit itself ‒ therefore, in order for the device to function, you need to provide it with an appropriate body..

Another important issue is power supply. Here, the range of products provided by the manufacturers varies: some circuits (e.g. audio amplifiers) will require a separate, symmetric (bipolar) power supply, which is achieved using a specialist transformer, bridge rectifier and regulating capacitors, or a two-channel laboratory power supply. Other circuits can have a very wide voltage tolerance (owing to the parameters of the components used in them), and require direct current to run, allowing them to work with many standard and commonly available desktop power supplies (sometimes even a laptop charger). In terms of power source, the simplest to operate will be battery-powered designs, or those that incorporate a voltage regulator and protection into the circuit. It is also increasingly common to see kits that include a coaxial power socket, which makes it much easier to adapt the device for everyday use. Unfortunately, kits adapted for power supply via cables, connectors and USB chargers are still rarely offered.

It is also worth mentioning that some of the circuits (again, audio amplifiers can serve as an example here) require cooling, e.g. by means of a heatsink.

Transfer Multisort Elektronik (TME) is one of the world’s largest global distributors of electronic components, electrotechnical parts, workshop equipment, and industrial automation. The catalog includes over 1,300,000 products from 1,300 leading manufacturers. TME’s modern logistics centers in Łódź and Rzgów (Poland), with a combined area of over 40,000 m², ship nearly 6,000 packages daily to customers in more than 150 countries.

TME also invests in the development of knowledge and skills of young engineers and electronics enthusiasts through the TME Education project, and supports the tech community by organizing the TechMasterEvent series, promoting innovation and experience exchange.