Connect 2 phones to each other. Easy communication between two phones

Telephone is an electrical device that allows people to exchange information over a distance using electrical signal. The word telephone came to us from ancient Greece. Tele - translates as "far", and background - "voice".

After reading the article, any home master can easily connect a landline, fax or several parallel phones, including a radiotelephone.

What is the voltage in the telephone line

The telephone line is live direct current 40-60 V if the phone is not connected or connected but the handset is on telephone set. During a call, the voltage in the communication line becomes variable with an amplitude of up to 120 V. When you pick up the handset, the voltage drops to 6-12 V. This voltage is not life-threatening, but it can cause discomfort.

It is impossible to disable the communication line or damage the telephone set during connection. The telephone line may be disconnected for several minutes if the handset is picked up for a long time without dialing, or if the wires of the communication line are short-circuited. The telephone line is automatically switched off by an automatic telephone exchange (ATS) to save electricity. So you can safely proceed to independently connect the phone to the communication line.

Before connecting a fixed telephone, fax or radiotelephone to the communication line, it is desirable, but not necessary, to check that the communication line is ready. Line voltage can be measured with a voltmeter, designed to measure direct voltage.

If the phone is not connected to the line or is connected, and the handset is on the phone, the device should show a voltage of 40-60 V. If there is no voltmeter, you can check using potatoes, and this is not a joke, but real way checks. It is enough to stick the noodle wires stripped of insulation into the cut of the potato. Batteries are not needed, as the wires are already energized.

What current will flow
in the event of a short circuit in telephone line wires

The automatic telephone exchange has a protection system against failure of equipment and communication lines, which limits the current when short circuit telephone line up to 40 mA.

For the communication line, one of the free pairs is taken, brown or blue. A twisted pair cable consists of two wires twisted together. The insulation of one of them is painted with a solid color, and the insulation of the second is white with stripes of the color of the first.

Having two telephone sets, a coil of two-wire wire of sufficient length and not a large number of radio components, you can organize your own telephone line for two subscribers. For example, to arrange a connection between two neighboring apartments by throwing a wire between the windows, or between neighboring country houses, between the house and the gazebo. First of all, let us recall from the school physics course how the telephone works. In the simplest case, these are two telephone capsules interconnected by a two-wire line.

When they speak in front of one capsule, its magnetic membrane moves from sound waves and induces some AC voltage, which goes through the wires to the coil of the second capsule and sets its membrane in motion. It turns out that the membrane of the second capsule moves in the same way as the first, creating sound waves that can be heard. But theoretically, such a connection is ineffective, too large losses in the wires and low efficiency of the capsule.

Therefore, a real telephone set has a carbon microphone, the resistance of which changes in time with speech. In addition, a certain constant voltage is supplied to the line. As a result, it turns out that a carbon microphone connected to the line, changing its resistance in time with the speech, causes a change in the current strength in the line.

Thus in the line it turns out alternating current, which changes in time with speech. This current feeds the capsule of another telephone and emits sound waves that are quite distinct and loud.

A schematic diagram of a simple telephone line is shown in the figure. Two electronic telephones are used - handsets with push-button dialers, but you can also take simple
disk devices. They are connected by two wires. A constant voltage of 60-80V is supplied to these wires through the resistance R1. When the tubes of both SLTs are hung between these wires, there is a voltage of 60-80V, since in this state the internal resistances of the SLTs are very high.

Let's suppose that they picked up the phone TA2, while its lever switch connects its conversational node to the line and the resistance of TA2 decreases sharply, so much so that the voltage in the line drops to 8-10V (the voltage drops because resistor R1 and the resistance of the conversational node TA get voltage divider, and the line is connected just through this divider).

If you start talking in front of the TA2 microphone, the resistance of its conversational node begins to change in time with the speech, which means that the total resistance of TA2 also changes. In this case, R1 remains unchanged and the voltage in the line changes in time with speech. The telephone set TA1 is also connected to this line, and if you pick up its handset, you can hear what is being said in front of the TA2 microphone. If subscriber TA1 answers, subscriber TA2 will hear his voice. This way you can talk to each other.

To call a subscriber, the telephone set has a bell or a buzzer, it is always connected to the line when the TA handset is hung up and responds to any significant voltage drop in the line. If you pick up the TA2 handset, then the TA1 bell will "ring" once, because there was one voltage drop in the line, hang up - TA1 will "ring" again.

As part of the TA there is a dialer, push-button or disk, it doesn’t matter, in any case, it serves to create voltage drops in the line, these drops are received by the telephone exchange, count them and thus determine the subscriber number. In our case, there is no telephone exchange, but the dialer can be used to call the subscriber. If you dial the number "9" TA creates nine voltage drops in the line, which means that the second TA will "ring" not once but nine times, if the number "0" - ten times.

Thus, in order for you to call your friend on TA1 from your TA2 phone, you need to pick up the TA2 handset and dial "O" (or another number) several times in a row. As a result, TA1 will ring, your friend will hear the call, and by picking up the phone he will be able to talk to you. In the same way, you can call TA2 from the TA1 device.

The DC voltage to feed the line is obtained from mains voltage 220V using a transformer T1 and a diode rectifier VD1-VD4. The ripple of the rectified voltage is smoothed out by the capacitor C1. Transformer T1 can be made from a small transformer from network source to power toys or portable equipment. It is necessary to disassemble the source case and by connecting the transformer with an extension cord to the network, measure the voltage on its secondary winding. Suppose the voltmeter showed 6V.

We need 50 V. Now we disconnect the transformer from the network, disassemble its lamellar core and unwind the secondary winding (not the network one), carefully counting its turns. Let's say we counted 120 turns, this despite the fact that output voltage was 6V. Now we calculate how many turns this transformer has per 1V: 120/6 = 20, total 20 turns. We need 50 V, so secondary winding should contain 20x50 = 1000 turns. We take a thin winding wire, for example, PEV 0.06 or PEV 0.09, and carefully wind 1000 turns with this wire instead of the old secondary winding.

Then we assemble the core of the transformer. You can take a ready-made transformer that produces at least 36V and a maximum of 50V.
Diodes D226 can be replaced with any rectifier, for example, D7 or modern KD102, KD103, KD105, KD226, KD209. Capacitor C1 for a voltage of at least 100V and a capacitance of at least 160 microfarads. Resistor R1 with a resistance of 1 kOhm to 1.8 kOhm for a power of at least 2 watts. Toggle switch S1 of any type.

Structurally, the power supply can be connected to the line anywhere, near TA2, near TA1, or even in the middle. For example, if TA2 is located in an electrified room, and TA1 is in a garden gazebo, it is clear that the source is connected near TA2.

When installing, do not reverse the polarity of the connection of the capacitor C1 and diodes. For D226 diodes, a graphic image of the diode is applied on the case, along the case, so that you can understand the purpose of the pins.

Despite the rapid decline in the popularity of landline telephones, there are not so many people who are ready to refuse them flatly. Admit it, it happens that sometimes it is extremely difficult or even impossible to do without traditional communication.

To connect the device to the switching network, you need a low-current node, the installation of which you can handle yourself. We will tell you in detail how to connect a telephone socket without calling a wizard.

There is absolutely nothing complicated in the schemes and methods, and the proposed by us will help to deal with the issue. helpful information as well as photos and videos.

Constructions landlines are updated and improved every year. AND modern devices significantly surpass their predecessors, favorably standing out against the background of their high reliability and ease of use.

To ensure the smooth operation of the device, two conditions are necessary:

1. The presence of a valid communication line from the PBX.
2. Opportunity electrical connection stationary device to this line.

The only thing that does not change in the field of telephony is the principle of operation of landline telephones. However, there are significant changes in designs and connection methods.

Old and new options for telephone switching are presented in a photo selection:

Image gallery

From the tools for the work it is necessary to prepare:

• building level;
• cross knife;
• voltmeter;
• screwdriver
• wire cutters;
• graphite pencil;
• protective gloves;
• Double-sided tape;
• perforator (if mounting a new point).

When choosing a screwdriver, they are guided by the type of surface and dimensions of the screws used for fastening. To minimize the chance of injury electric shock, all manipulations are best done with a screwdriver, the handle of which is insulated.

Having outlined the location of the connection point, using building level adjust the horizontal and vertical position

To connect a hidden type socket, you must first make a hole in the wall for its installation -. This can be done using a puncher equipped with a special crown with a diameter of 60-70 mm.

In the absence of such, the work can be done with an ordinary hammer with a chisel. But manual labor will take much more time and effort. Then, to the hole made, it is necessary to drill a channel for laying the telephone cable.

There are certain nuances when installing a socket box in.

Stage #2: Stripping the ends of the veins

Before proceeding with the melting of the cores, it is necessary to strip the ends of the wires by removing the outer layer. Bare enough extreme 4 cm of the wire.

When stripping a telephone cable, remember that it is very vulnerable to damage. And broken wires will only lead to equipment malfunction. Therefore, it is important to use a specialized .

Since it is not always possible to carefully cut the first time, experienced craftsmen recommend making some margin along its length when laying the cable. The extra wire can then be hidden under the cover of the device.

Removing the protective insulation from the ends of the cable should be done very carefully, using a cross-cutting knife, a sharply sharpened blade or side cutters.

The task of the master is to strip the ends of the wires from the braid so that in their bare form they are intact and devoid of any defects.

Step #3: Connecting the Outlet Wires

Stripped wires with separated conductors are connected to the connectors of the box itself, focusing on the designations indicated on the front panel of the indoor unit. At closed method installation, for ease of connection, the wires are made protruding beyond the wall plane by 50-80 mm.

To observe the polarity when connecting wires, they are guided by the rule: red insulation on the line with the “-” sign, and green braid on the “+”

If the polarity rule is not followed, there is a high risk that the telephone will malfunction from time to time during operation.

At this stage of work, you will need a voltmeter. With it, you need to check the readiness of the communication line. The voltage in the line should be in the range of 40-60 volts.

The connected cable cores are applied to the clamp and tightly tightened with special screws, ensuring a secure fit. The shape of the grooves to which the cores are attached facilitates the installation process. It is not necessary to wrap the joints with electrical tape.

When connecting devices, the design of which is equipped with four fork-shaped contacts, only two central contacts are used.

When performing surface mounting, at the final stage it remains only to close the housing cover with a latch and fasten it with screws. The finished outlet is attached to the wall or floor, "planting" it on double-sided tape.

With a closed installation method, making sure that the wires are not intertwined in the socket, according to the applied markings, the indoor unit is mounted in the wall. Having given the block the desired position, the structure is fixed with expansion screws and self-tapping screws.

At the final stage, it remains only to eliminate the gaps between the socket box and the wall, covering it with gypsum mortar, and also close up the channels with the laid telephone cable.

After the gypsum has acquired the desired strength, the protective edging is put in place and the front panel is attached. In modern devices, the protective edging snaps onto the indoor unit, and front panel fastened with screws.

There is nothing difficult in connecting a telephone socket. The only thing is that you should not save money by purchasing equipment of low price range. It does not always meet the standards and can fail even at the connection stage.

Share your personal experience of connecting a telephone socket, leave comments on the article and ask questions. The contact form is located below.

Almost every user of a smartphone or tablet with Android OS sooner or later needs to transfer files from android to android? However, not all “users” can connect two modern gadgets together and create a reliable data transmission channel.

Therefore, in this article we will consider in detail the topical issue of how to connect an android to an android, and present the four most common and simple in terms of functionality ways to solve this problem.

How to connect android phone to android via bluetooth?

1. Connect two devices with operating system"Android" is possible with the help of "Bluetooth" technology.

To transfer files from android to android via "Bluetooth" you need:

Find in the "File Manager" or "File Directory" the very file that you need to transfer to another Android device;

Click on the selected file and select "Send" among the proposed actions;

You will see a window with a list of ways to send given file: You must select "Bluetooth" accordingly;

By entering the security key, confirm the connection to the device (if required) and wait for the file(s) to be transferred.

How to connect android to android via wifi?

1. To connect android devices to each other, you can also use a wifi connection.

Of course, you won’t be able to get by with just a wifi module: to exchange data, you will need to download a specialized software(for example, "Fast File Transfer").

However, connecting android to android via wifi has a number of advantages, including:

• - data transfer rate at wifi connection significantly higher than with using Bluetooth adapter
• - file exchange can be organized between devices with different operating systems;
• - Implemented the ability to use "QR-codes".

To connect two android devices via wifi, you need to download and install the appropriate application, then run it and follow these steps:

At the first stage, you will be prompted to enter a "device name" (Device name) - for example, "Proverka" - and a password to establish a wifi connection;

Listed possible ways file transfer, select "Fast File Transfer";

Now on the phone / smartphone, which is the "receiving" party, and in the search available points access, select the connection whose name you specified in the first step - "Proverka", and connect by entering a password;

After a successful connection, an address will be indicated at the bottom of the application window, which must be written in the address bar of the browser;

After going to this address, the browser will automatically start downloading the file you have selected.

How else can you connect an android phone to an android?

In addition, you can use another great application called "Filedrop".

In this case, to connect two "androids", follow the same initial steps: download the application, install the software (on all devices) and run it. The first time you launch the application, you will need to grant access to files, folders, etc.: confirm the permission and just drag and drop desired file to the icon of the device where you want to transfer it (smartphone, tablet or computer).

How to connect android to android via internet?

To create and share on a smartphone / tablet, you will need to download and install the ES Explorer file manager. Software setup consists of the following steps:

Run the program and select the "Network" section in the menu;

A window will appear with the name of the connected network - click the "Enable" button;

The next step will be the address that you need to remember.

You will need it to synchronize with devices (for example, "199.199.199.199:2233");

Click "Create" - "FTP"

Now specify the address ("199.199.199.199:2233") in the "Server" line before the "colon", i.e. 199.199.199.199;

In the "Port" line, write the numbers indicated after the colon: 2233;

Click "OK", open the created folder (of the same name with the address) and select the actions you need (copy/move/delete, etc.).

It is worth noting that this application free and, in addition, includes such features as:

• - support cloud storage("Google Drive", "OneDrive", "Dropbox", "Box.net", "Sugarsync" and others);
• - integrated "RAR" and "ZIP" archivers;
• - support not only "FTP", but also "FTPS", "SFTP" and "WebDAV".

You can list all the possible functionality for a long time, respectively, for connecting Android devices to Android, this application is one of the best solutions.

Often a situation arises when the question becomes relevant: “How to connect two phones together?” For example, you need to copy big file with a video or program from one phone to another. Or move a large number of music records and photos. In addition to the traditional sending of files via Bluetooth and Wi-Fi channels, there are several more ways. This article will show you how to connect two smartphones with a USB cable.

Is it possible to connect smartphones with a cable?

In order to connect two phones with a cable, you need to have a micro-USB cable - USB and a USB-female adapter for "OTG" in stock. To begin with, it is worth noting that only phones that support the One-touch-Go (OTG) function can be connected. Thanks to this technology, you can connect any peripheral device, including the second phone.

USB adapters can be labeled "master" or "slave", that is, they can be master and slave. If there is an adapter marked "master", then the phone with this adapter will be the main one, and the second phone will be displayed on its screen as a removable media. If the adapter is marked "slave", then the situation will be mirrored.

All modern smartphones support OTG technology. It was designed to connect a keyboard, webcam, removable media, printer, mouse, and other peripherals to Android devices.

To connect two phones, you first need to connect a USB-female adapter to one phone, and a micro-USB cable to the second phone. After determining the cable and adapter by the phones, you can safely connect them together.

When connecting two phones, you do not need to use additional software. For this, the interface of a standard smartphone file manager is enough. In this case, the contents of the slave phone are displayed in file manager the main phone as the contents of the removable media. After connecting the phones with a cable, you can copy files at high speed and not worry about a possible disconnection or data loss, as is the case with data transfer via the Bluetooth channel.

How to connect a smartphone with a tablet?

No less popular than smartphones today are tablets. And so the question of how to connect a tablet to a phone with a USB cable arises quite often. Moreover, most modern users often have both of these devices. And sometimes it is very necessary to quickly copy a large amount of information from one of them to another.

As in the situation with two phones, a micro-USB cable - USB and a USB-female adapter for the "OTG" function will come to our aid. But some tablets already have a built-in USB interface. In such a situation, the task is simplified: only a micro-USB to USB cable is required for connection. Just remember that the built-in USB-female often has the manufacturer's label "master", and take this into account when connecting.

Once you know how to connect your phone and tablet via a USB cable, transferring information between the two devices is even faster and more reliable. Of course in the world wireless technologies this option is not always necessary. But situations are different. For example, one of the devices is broken wifi adapter. Then data transfer via the USB interface will be the only and no less reliable way.