DIY antenna creation for a 3g modem

Mobile Internet is a convenience and the ability to always stay in touch. One can safely say that such an achievement is already a step in itself into the future, when information is needed constantly and at any step.

Mobile data technology is not yet so perfect as to be available at any given time, but is constantly evolving.

One of the convenient ways to access the Internet is familiar to many: this is the use of a 3G modem. This device is capable of catching the Internet, which is transmitted over mobile networks. Thus, it is now possible to be online in the country, in the country, in the park. The quality of the transmission will directly depend on the signal strength. Therefore, the problem of enhancing the reception of a mobile network using a 3G modem is relevant today.

How can I strengthen signal reception with a 3G modem

A feature of the standard 3G modem is that it has a rather weak antenna connector. He is quite capable of catching a signal in the conditions of the city, but problems can arise with a noticeable distance from the transmitting tower.

Standard signal conversion connector

It is because of this that there is a need to strengthen signal reception. In villages, suburban villages, you can successfully catch a mobile network, even at a considerable distance from the tower. There are several ways to do this:

• make a directed trap of radio waves;
• Connect the antenna to the 3G modem using soldering.

The easiest option is to position the modem most successfully so that the signal is caught stronger than usual. Extenders with USB adapters are often used for this. Their usual sizes are 3-5 meters in length. This is enough in most cases to choose the best location for a 3G receiver on the window, outside the window or in the room.

As an additional measure, antennas that do not connect directly to a 3G modem, but noticeably amplify the signal, have proven themselves well. They are simple enough to manufacture, and their work, at times, is enough to ensure a stable and high-quality reception.

An example of the simplest homemade signal amplifier for a 3G modem

When the network is not caught at all, some craftsmen make the well-proven Harchenko antenna. Such devices today can be purchased at radio stores or made independently. Why do they catch radio waves of the mobile Internet as well as possible? Because these antennas are precisely sized for the transmitted wavelength, they are often soldered to the main connector of the 3G modem, making reception the best, almost as possible.

But you will have to tinker with the Harchenko antenna if you try to do it yourself.

The first option is directional devices

When there is a signal on a 3G modem, but it is not strong enough, you can do with quite simple devices in order to achieve better quality of mobile Internet reception.

Usually this measure is to better position the modem and direct its standard antenna in the desired direction (towards the tower). For these purposes, an ordinary tin can, an old pan, dishes, or even a simple disk may be suitable.

For example, if we talk about a can antenna, you just need to punch at the base or bottom of the hole in which the modem itself would be securely mounted. In fact, the signal should increase significantly if you choose the right direction.

Homemade Canned Antenna Example

Even easier are those who use old drives to amplify the signal. The main thing is that they are opaque. But great achievements from this method should not be expected.

No special engineering skills are needed if old dishes are adapted to enhance signal reception. Colanders or pans with handles are particularly suitable. Then on the handle you can fix the USB-wire, and the modem itself a little put out in the interior of the dishes like this:

Another easy way to improve signal reception with a 3G modem

The second option is an external antenna

An external antenna for a 3G modem is also quite successfully done by one’s own hands. Moreover, this also does not require too much time and effort, and the signal quality will definitely please.

The main idea in this work will be to create high-quality insulation, so that the device can work in any weather, as well as choosing the optimal signal direction point.

The insulation tape can successfully cope with the insulation. Perhaps this is the most versatile way to prevent moisture from entering wires and connections. But it’s important not to layer the place where the device has an integrated trap, otherwise the signal will be worse and all the effort will be wasted.

As a reflector that will “collect” the radio waves, a metal sheet may come up. Well, if you can make it a little rounded to concentrate the signal at one point. You need to act on the principle of the well-known satellite dish.

Metal sheet reflector

For such a signal amplifier, even ordinary cardboard can come up if there is nothing metallic at hand. But the cardboard base must be covered with foil, otherwise the signal will not be reflected.

As it has already become clear, any metal can be used as a reflector. It is only important that he concentrates the radio waves at the point where the modem is fixedly mounted. Craftsmen fit for external antennas everything that at first glance seems like garbage. For example, the case from the old monitor, cut out the bottom of a large pan. If you try, you can get a very neat, beautiful antenna, which also perfectly copes with its functions.

The old monitor came in handy

The third option is the Kharchenko antenna

Harchenko’s antenna began its life in the middle of the twentieth century. But for such a long time its design has not changed at all. The principle of operation is based on the capture of electromagnetic waves, through which mobile Internet is transmitted.

How to assemble the Harchenko antenna with your own hands today is described in many sources. Different options may differ externally or with the materials used, but the principle of its action remains the same. It can be argued that the Kharchenko antenna significantly improves the quality of the received signal. It is useful in cases where the usual methods of indoor or outdoor devices are clearly not enough.

The great advantage of the Harchenko antenna is the range. Due to the fact that the signal is repeatedly reflected in the atmosphere and goes around obstacles, it can be caught at a considerable distance. It is important only to correctly assemble the components in a single circuit. But knowing the main parameters, there should not be any special difficulties with this.

• So, the key element in the Kharchenko antenna is the main element that receives the signal. For the frequency of 2100 MHz, on which mobile Internet is transmitted, you should choose a copper wire with a cross section of 3.5 to 4 mm. With the help of pliers, it is necessary to set the shape of two rhombs with the help of pliers (during the experiments it turned out that this is the best form for receiving a signal, although bicquadar models of the Harchenko antenna exist where four rhombuses are connected in series). It is very important to observe the length of each side. It should be 53 mm for a good reception of the wavelength (143 mm). In general, there are tables for calculating the side of faces for a given wavelength.
  And another quality of the copper wave channel receiver is that the angles should not be exactly 90 degrees. This is due to reduce current resistance inside the antenna.That is why the bends do 120 degrees, which sets the diamond shape, not square.
• An important point - in the center of the antenna should not be connected. There you need to organize the fastening of the cable that is output to the 3G modem. By the way, cable connection also has its own subtleties. For example, many low-cost models today are not soldered, so then you have to buy a regular F-connector. It is not expensive, and the wires are simply wound and insulated on the cable. The connector itself is easily soldered to a ready-made antenna with the help of a copper wire.

Adapter connection

• The next step is to connect to a 3G modem. There may also be options. Very often it is enough to simply wind the wire outlet with copper wire around the device. But in order to maximize the reception of the signal, you can either completely disassemble the case (it is sealed, so you have to break it), or cut off the part in the place where the internal antenna is located. The wires are soldered to it.
• To maximize the signal, an irradiator or reflector is necessarily made of metal in the Kharchenko antenna. It is installed behind the diamond-shaped receiver and it is important that the device does not come into contact with the antenna, otherwise the signal will be lost. To prevent currents from flowing, you can mount the reflector with plastic. For example, a deodorant cap is suitable for these purposes. It will ensure sufficient removal of the plate (it is recommended to maintain a distance of 36 mm) and insulation.

So simplified, you can imagine the final version

Whatever antenna is chosen to enhance the reception of a 3G modem, it should do its job well. Somewhere you can do with quite primitive, simple devices, and somewhere you need a thorough approach. In any case, all the work can be done independently and not know the problems with receiving a good signal. And if you look at old, unnecessary things, it is likely to do without significant expenses.