Antenna 433 MHz. Antennas at 433 MHz with their own hands

In most cases, when it comes to antennas, people imagine large "plates" that are installed outside the window or on the roof of the house. However, it is worth noting that this is far from the case. The fact is that the size of the antenna depends on what frequency and wavelength it will catch. Naturally, if you want to catch the satellite signal to broadcast several dozen television channels, then you will need a large antenna. But not always you need such a signal. That's why it's worth considering such a thing as the 433 MHz antenna. This device is very different from those antennas that you used to see on windows and roofs. It is very small and, as already can be seen by the name, does not take the longest waves of the signal. Why such waves can be useful? Most people do not pay attention to them, however, if you like filling your house with various items working on remote control, then you definitely will need far more than one 433 MHz antenna. If you learn to use their properties, you can create in your apartment such things as a radio wall socket or even a feeder for a pet with remote control. Are you interested? Then read the article further and you will find out what the given antenna is, how to use it, where to buy it, and most importantly - how to make it with your own hands, if you do not want to spend money on buying.

What is this antenna?

So, first of all it is necessary to understand what the 433 MHz antenna is. As you could already understand, this is a device that allows you to set up a specific device for a particular frequency, then interact with it. By installing the antenna into a specific device, you can then send it a signal at a certain frequency to activate this device and monitor it. This is a very useful feature in any home, since you can greatly simplify many processes. However, not everyone will be able to do something like this - you need to be well versed in this area to adjust the instruments to the desired frequency. But if you set a goal, you can definitely reach it. You just have to try hard, and start with studying this particular antenna, because it is one of the most important elements. You definitely need to know that the 433 MHz antenna is of three types: the whip, spiral and etched on the PCB. How do they differ? Which is better to choose? This is exactly what will be discussed later. You have to find out what each of these antennas represents and what is best for your specific purpose.

Whip antennas

How can you get an antenna at 433 MHz? It's quite easy to make it with your own hands, but you can also get it ready, which will cost you a bit more, but it will save a little time. In any case, you first need to decide what type of type you want. And the first type, which will be discussed, is a whip antenna. Its main advantage is that it has the best technical characteristics compared to the rest of the species. That's why almost always people make a choice in its favor. Moreover, it is much easier to make it with your own hands. So, in general, this is the best antenna at 433 MHz, made with own hands or bought in the store. However, you do not need to think that it is perfect. If this were the case, then there would simply be no need for other kinds. That is why you need to separately consider the shortcomings that this type of antenna has, so that you are aware of all the features before making a purchasing decision.

Disadvantages of whip antennas

The first drawback of having a 433 MHz pin-shaped directional antenna is the susceptibility to environmental influences. The problem is the very strong reflection and interference that occurs if you try to use the antenna indoors. Thus, it is more suitable for portable devices, and not for home appliances, because in homes because of the small amount of space, obstacles in the form of furniture and walls, the signal can be distorted, lost and not reach the target device. So first of all you should think about the purpose for which you are going to use the antenna, and then decide on its purchase. However, this is not the only drawback of whip antennas, which could initially seem ideal. It turns out that the pin in this antenna should be practically (or completely) parallel to the grounded plate on which the structure itself is located. As you can easily understand, in small household appliances it is very difficult to implement. Therefore, you could already understand that the 433 MHz pin directional antennas are best suited for various portable devices of more or less large dimensions or those on which the antenna can be installed from the outside. At home, it is not recommended to use such antennas. But what to replace them then? As you remember, there are two more kinds of such antennas, so it's time to pay attention to them.

Spiral Antennas

The easiest way is to give you a pin-like homemade antenna at 433 MHz, however, as you may have noticed above, it is not ideal. Therefore, it is worth paying attention to other types, for example, a spiral antenna. How is it different from the whip? First, it also has good technical characteristics, so in this regard you can use with complete tranquility both the first and the second kind. What about jamming? It turns out that they are also present in the spiral antenna in enclosed spaces, and sometimes they are even stronger than those of the whip antennas. Therefore, it remains to look at the last parameter - compactness. As you remember, whip antennas because of the design feature should either be placed on the device body, or inside it, but there should be quite a lot of free space inside the device, which is difficult to achieve when it comes to small home appliances. And according to this parameter, the helical antenna bypasses the whip antenna, because it is extremely compact and will allow you to make radio-controlled almost every device in your home. Naturally, a 433 MHz homemade directional antenna made in this way will take you much longer, but if you are going to buy an antenna, then you definitely should take a look at the spiral versions, as they can help you and help you very much.

Antenna on the board

If you need a high-quality compact collinear antenna at 433 MHz, then you definitely should pay attention to this kind, that is, to the antennas that are embedded in the board. This means that this species is impossible (or very difficult) to do by one's own hands, therefore they will be considered only as purchased. What are their advantages over the two types described above? First of all, they have good characteristics. Of course, not as impressive as the previous two options, but good enough for everyday use. Their main advantage is compactness - such antennas can be placed absolutely in any device. But, as already mentioned above, their main drawback is that the dual-band 144-433 MHz antenna on the board made by own hands is something fantastic. This is why this variant will not be considered further because the rest of the article will be devoted to the creation of the antenna with our own hands. How difficult is it to do? What is needed for this? You will learn all this later.

Necessary calculations

But if you decide to make an antenna yourself, then you will need a lot of theoretical knowledge on this topic. The fact is that any deviation in the manufacturing process will not allow you to tune the antenna to receive a specific frequency. Therefore, everything must be done very accurately, so it's always recommended to start with calculations. Making them is not so difficult, because all you need to calculate is the wavelength. Perhaps you understand physics, so you will be much easier, as you will understand what is at stake. But even if physics is not your strongest side, you do not need to understand what each variable means to make the necessary calculations. So, how is the length of the 433 MHz antenna calculated? The most basic equation that you need to know is that which will allow you to calculate the required length of the antenna. To do this, you must first calculate the wavelength, since the length of the antenna is one quarter of the wavelength. Those people who understand physics, can calculate the necessary wavelength for a particular frequency: in this case it is 433 MHz. What needs to be done? You need to take an indicator of the speed of light, which is constant, and then divide it into the frequency you need. As a result, it turns out that the wavelength for a given frequency is about 69 centimeters, but with this detailed adjustment it is better to use more accurate values, so it is worth saving at least two decimal places, that is, the final result is 69.14 centimeters. Now it is necessary to divide the received value by four, and you will get a quarter wavelength, that is 17.3 centimeters. This length should be your J-antenna 433 MHz or any other kind that you want to use. Remember that regardless of type, the length of the antenna should remain unchanged.

Use of the received data

Now you need to use the data that you got, in practice. An antenna 144-433 MHz can be made in various ways, however, the practical application of theoretical information should always be the same. What is it about? First, you must always take the wire a few centimeters longer than the desired length of the antenna. Why? The fact is that in theory everything turns out quite accurately, but in practice everything will not always work the way you plan. Therefore, you should always have some reserve in case something goes wrong or the signal is not caught at the frequency you wanted. It is always possible to bite off the wire at a particular place easily when you determine the required length. Secondly, you should always remember that the length is measured from the place where the wire comes out of the base. Thus, the resulting 17 centimeters should be counted from the bottom of your antenna. Most often you will need to use a slightly longer wire, since you will need to solder your antenna. The 433 MHz pin antenna will work better, the more pins you use, so you should make sure that each one is the same length.

Preparation of materials

So, with the theory over, it's time to practice. And for this you will need to take all that you need to create your own antenna. First of all, this wire or rods, which will constitute the main receiving part of your antenna. Secondly, you will need a base for your antenna. It is desirable that it has several holes, which you can use to fix the pins. If these holes are not, you will either drill holes, or solder directly to straight metal, which is not very convenient and will not allow you to calculate the length in advance. Therefore use the base with the finished holes. Naturally, you will need other things, such as, for example, a soldering iron, but everyone knows about it, so it makes no sense to list all such items.

Performance of works

First of all, you need to prepare the material for further work. To do this, all the pins you need to clean, zaludit and processed with flux. After that, you need to cut the pins to the required length, but do not forget to leave a little length to adjust the finished result. Then you need to take up soldering - each of the pins must be sealed on the back of the antenna, and then take another one, which will be attached to the antenna. Its length no longer plays a role, since it will perform the function of the holder and will not be responsible for receiving the signal. It also needs to be sealed, after which you can already admire the result of your work.

Final Steps

Well, your antenna is ready for use. You have only to make the final steps. Cut off the extra length of the pins to make the signal perfectly. If you have a shrink - use it. And remember - this is just one example of a self-made antenna. You can also make a spiral antenna, and the whip antenna in your performance may look quite different. However, calculations to obtain the antenna length are relevant in any case, and the steps to create an antenna with your own hands will also differ only in details.