DSL-2500U. The owner of this modem complained about the permanent dumps of the Internet, and even at all refuses when connected. And indeed, turning on the modem, I found that even through an Ethernet modem is unavailable, although the bulbs are blinking as it should be.
Disassembly and repair of the modem D-Link DSL-2500U
First, determine whether the power supply is guilty to 5V. We measure the voltage - deviations are allowed plus-minus 10%. If there are suspicions of the power supply, then it and change swollen capacitors. Usually this C9, C10, sometimes C3. If the power supply is out of suspicion, then disassemble the router. We unscrew the four Samorza under glued legs.
Replacing capacitors in the D-Link DSL-2500U modem
Under the lid of the router we see e-board with swollen condensers. Capacitors are usually overheated C8 - 470 μF x 16 V, C14 - 100 μF x 16 V, C32 - 470 μF x 16 V, C111 - 470 μF x 16 V. We change them to the capacitors of the same or greater capacity. 
Condensatory C14 Best replace 220 μF. 
As a result, repair has been successfully carried out. modem d-link DSL-2500U - he began to work stably. It seems that nutrition pulsation due to the low filter tank overlap data signals and disappear synchronization. Hence the loss of communication and the unstable work of the modem. 
Other malfunctions of the D-Link DSL-2500U modem
Also, sometimes, fails of a microcircuit U2 Broadcom 6301KSG.. I found the solution to this problem. The source states that the microcircuit may be replaced with AD45048..
Which in turn is quite simple replaced with assembly on favorite CT315g and resistors MLT-0,125 430 ohms. True because of the scatter on the current coefficient, you have to select resistors for the stable velocity of the Internet. Also transistors can be replace on C945.and resistors can be selected up to 20 com. 
Among other frequent malfunctions, D-Link modems often encounters a breakdown of an external power supply. It may also communicate with the network and periodically fall off the modem itself. In this case, the repair will consist in replacing filter electrolytic capacitors in the power supply.
On this I complete the note about the repair of the modem D-Link DSL-2500U.. I hope that your modem will work stably for many years.
DSL is decrypted as a Digital Subscriber Line (digital subscriber line). DSL is one of the technologies that allows ordinary copper pairs to combine local networks, telephone exchanges, provide access to remote corporate networks, provide access to the Internet. For the organization of the DSL line, existing telephone lines are used; This technology is good and good that does not require laying additional telephone cables. Modern DSL technologies enable the organization of high-speed Internet access for regular user and enterprises and organizations, turning ordinary telephone cables to high-speed digital channels. Moreover, the data transfer rate depends only on the quality and length of the line connecting the user and the provider (from 32 Kb / s to 50 MB / s). Based on the above, it is possible to make an initial conclusion about DSL technology: DSL technology allows you to organize high-speed channels on existing copper lines, which entails a decrease in the financial cost of an enterprise or organization to connect to the Internet and associate remote LANs.
SDSL (Single Line Digital Subscriber Line - Single Digital Digital Subscriber Line)
SDSL - technology that provides symmetrical data transmission with speeds from 64 Kb / s to 2 MB / s. In the SDSL technology, only one pair of wires is used to organize a digital channel, the maximum transmission distance is limited to 8 km (the diameter of the copper vein 0.5).
ADSL (AsymmetricDigital.Subscriber.Line - asymmetric digital subscriber line)
ADSL is a technology that provides asymmetric data transmission, that is, the data rate from the network to the user is significantly higher than the data transfer rate from the user to the network. ADSL is an ideal technology for organizing access to the Internet. When organizing such connections, users usually receive a much greater amount of information than transmitted. 
HDSL. (HighBit.- Rate.Digital.Subscriber.Line - high-speed digital subscriber line)
HDSL is a symmetric data transfer technology, that is, the transmission speeds in both sides are equal. Due to the transmission rate (1.544 MB / s for two pairs of wires and 2.048 MB / s for three pairs of wires), telecommunication companies use HDSL technology to organize T1 / E1 channels.
So, briefly becoming acquainted with DSL technology, you can make some conclusions. DSL technology provides high data transfer rate. Different variants of DSL technologies provide different data transfer speeds, but still the speed of this equipment is much higher than the speed of the usual modem. DSL technology is the most cost-effective option for the unification of the LAN, telephone stations, the organization of Internet access and access to corporate networks of an enterprise or organization.
VDSL - The most modern XDSL solution, product evolution and convergence of ADSL and G.SHDSL technologies.
Compared to ADSL, VDSL has a significantly higher data transfer rate: from 13 to 56 Mbps towards the user to the user (downstream) and up to 11 Mbps from the user to the network (Upstream) when working in asymmetric mode; The maximum bandwidth of the VDSL line when operating in symmetric mode is approximately 26 Mbps in each direction of transmission. Depending on the required bandwidth and type of cable, the VDSL Length lies from 300 meters to 1.3 km.
Connection diagram.
The cable from the phone to the splitter in the table is not included, as this cable usually goes complete with the phone.
Description of the network scheme
To build a network, you need to install a multi-port industrial DSLAM switch in the CSD. From the switch there is a RJ-11 telephone cable to a splitter, a telephone connection is also possible to splitter. Splitter via RJ-11 connects to the phone cable and on this cable there is a signal to the enterprise. The company connects everything in the reverse order: the splitter is connected to the modem via RJ-11, to the modem via RJ-45, the electricity meters in turn on RS-232 are connected to the modem. Phone cables are not included in the calculation, as the telephone operator networks are used.
|
Name |
Price, rub |
number |
Cost, rub |
|
|
D-Link DSL-2540U modem | ||||
|
Splitter for ADSL modem D-Link "DSL-30CF" | ||||
|
Dlink DSLAM-3248 / DC / C | ||||
|
Patch cord RJ-11 1 m | ||||
|
Patch Cord UTP Cat 5e. 0.5 m with connectors | ||||
Specifications of equipment
DAS-3248 / DC / C
Thanks to the Network Uplink Gigabit Ethernet (GE) interfaces, IP DSLAM DAS-3224/3248 provide a cost-effective solution for direct connection to IP networks via an Internet router or LAN switcher. IP DSLAM allow providers to organize broadband access to copper networks using existing telephone communication lines. Devices support ADSL / ADSL2 / ADSL2 + technology and advanced IP services, including QoS, multicast and subscriber management. These functions contribute to eliminating bandwidth overload and ensure noise-protective and efficient video, voice and data data transmission. Triple Play technology provides simultaneous transmission of content, demanding of bandwidth: voice, video and data - through a single infrastructure. The DAS-3224/3248 series devices support UPLink channel aggregation (Combine UPLink channels GE to one logical interface). In addition, thanks to the Daisy Chaining option, all connected devices can use one UPLink-channel GE. Equipped with 48 ADSL2 + ports.
DSL-2540U / BRU / C 
The DSL-2540U / BRU / C modem is designed for small offices and home networks. It allows you to quickly and easily get broadband Internet access and share the ADSL communication channel by several users. Thanks to the built-in ADSL interface that supports the downstream speed of up to 24 Mbps, firewall, QoS, and the built-in 4-port switch, this device provides small offices and home users a convenient and economical way to create a safe, high-speed network, with free "narrow »Floor communication channel to the outside world.
DSL-30CF / RS
The plootter is required when using one telephone line for voice and data transmission (ADSL).
AdSL, ADSL2, ADSL2 +, Annex A, L, M standards are supported.
1 RJ-11 connector for connecting to a telephone line
1 RJ-11 connector for connecting phone (or mini-PBX)
1 RJ-11 connector for connecting ADSL - modem
---->
---->
---->
Repair ADSL Modem DSL-2640U Version C1.
Wings P. V.In that sample modems
Which I got under his hands, about 80% of faults were the following kind:
periodic blinking of all LEDs
periodic Reset ADSL Connection
periodic reset LAN
The assumption that these are bad electrolytes in the Modem BP, in principle, was confirmed. So, we open the modem. We tear the four gums from below and unscrew the screws.
General view of the modem board in the following photo
The following photography capacitors for which special attention should be paid. They are circled with white lines. This is 2 electrolytes of 2200 μF by 25 volts and one 470 μF for 16 volts. They are usually fumes, the rubber bands are squeezed.
If there is an oscilloscope, you can see the level of ripples at the output of the secondary power source of 3.3 volts, just there is a capacity of 470 μF to 16 V.
That's the same, not very glad picture. At a voltage of 3.3 volts, the ripple is about 0.5 volts. Capacity for 470 μF change unambiguously.
The result of work.
Conclusions.
Technique is not the worst, modems are very rarely dying from external influences, but for round-the-clock work is not adapted. Will it work, turn off the modem, pull out the adapter from the outlet, and better and add an adsl line.
The 2500U DSL modem allows you to connect the subscriber's computer to the Internet using telephone cable links. It finds its application where the gasket of modern high-speed communications is so difficult.
On the basis of this router 2500U, it is impossible to organize a full-fledged local network, since the DSL does not have a wireless communication module. But the principles of configuring the connection of the device with the provider are used in more "advanced" routers.
The D-Link network device does not support many functions, without which new models are not competitive in the market.
The main of them includes parameters relating to absence:
- built-in WiFi module to create a local wireless network on its base;
- USB connectors for connecting external drives, mobile 3G / 4G-modem wireless Internet;
- ports for connecting with high-speed FTTX fiber optic cable.
Appearance DSL-2500U
The delivery package of purchased via the trade network includes:
- ADSL modem;
- splitter - a device that allows you to split the signal to the low-frequency (analog) signal when connected to the input telephone line for a telephone and high-frequency (digital), used in the modem;
- two cables with RJ-12 connectors, one of which connects the splitter and telephone, and the other - the output of the splitter and the DSL modem input;
- patch Cord with RJ-45 connectors to connect the router to enter the computer or laptop network card;
- modem power adapter from alternating current network;
- paper Operation Manuals and CD-disk.
The following elements are located on the rear panel of the router 2500U:
- dSL connector for connecting the product with a "modem" output from Splitter;
- lAN connector to which network devices are connected;
- 5B plug connector \u003d 1a for network power adapter;
- oN / OFF button (available on all series);
- the Reset button to reset the current settings to the default factory values.
The DSL front panel is designed to inform the user about the status of the connection lines of the connected equipment and the individual component parts of the modem 2500U. The indicators located on the front panel of the device are as follows:
- Power signals about the DSL modem power out or turned off.
- Status informs about the operation of the router of 2500U or errors.
- DSL shows the synchronization status of the router in the process of working with the provider.
- The Internet determines the presence of a connection with the "World Wide Web" or the presence of critical errors in the line (red glow).
- LAN informs about the service life when the devices are connected to the port.
Connection 2500U and preparation for work
A telephone cable is connected to the DSL router connector, which is connected from the Schlitter Modem connector or directly from the ADSL telephone line, headed into the apartment or house. The name "Asymmetric ADSL" is sometimes hearing, but not entirely correct. Asymmetry is already laid in the ADSL abbreviation in his first Latin letter (asymmetric). 2500U LAN modem connector using patch cord is connected to a PC or laptop network card connector, usually built into the motherboard.
AC network adapter is last connected. Subsequent configuration of Internet connection is performed with both devices activated. The splitter of the individual power does not have. For the 2500U router, it is necessary to receive an IP address, as well as the address of the DNS server in automatic mode using the TCP / IPv4 Internet protocol.
To configure the modem D-Link model 2500U under any provider, you need to disclose its interface. This is done using a PC or laptop connected to the LAN port. In the address bar of the Web browser used on the computer, you must enter the value 192.168.1.1. It is indicated in the attached instruction manual. Then click on the ENTER keyboard. In the window that opens, you must fill out the "User Name" and "Password" fields.
By default, for most routers, these values \u200b\u200bwill be the username and password Admin / Admin. After that, you need to click "Login". Next - the transition to the main page of the interface, for different versions of software firmware (software) has its own appearance.
The DSL-2500U router for auto-tuning requires the "Connect Internet" tab (Quick Setup, Wizard) on the main page of the interface. The DSL modem configuration produces "Settings Wizard". He requires data received by the user from the provider. The 2500U setting is essentially semi-automatic, since at different stages of its holding it is necessary to manually enter data from the contract. To go to the next step, click on the stencil "Next".
Versions modem 2500U presented a lot. From here you can see a variety of WAN interfaces. At first step, you must select the connection type: PPPOE, PPPOA, IPOA, IPOE, Static IP, "Dynamic IP", Bridge. 
With a sequential continuation, the DSL configuration will be required to additionally enter the values \u200b\u200bof the parameters VPI, VCI, depending on the register of the operator providing services. 
For PPPoE connections, PPPOA requires a username and password provided by the provider. They remain unchanged. Entered only when setting up 2500U and are saved with subsequent equipment inclusions. 
Static IP requires an appointment of the Internet address assigned to the provider (paid) stored unchanged throughout the operator's work. Dynamic IP does not require any actions from the user when configuring an Internet connection.
Connecting to the Internet manually on the example of some providers
With manual configuration, it is possible to configure a 2500U modem for the user and set all the necessary parameters, not excluding those that need to be mandatory for the type of connection of each Internet operators. On the DSL modem administration page, you need to go to the Advanced Setup tab.
"Home ru"
After entering the extended settings of the router 2500U, click on the "Network" tab in the top row and enter its menu. Further select the WAN section, click "Add". The operator uses PPPoE-. It must be selected from the proposed list. 
In the "Username", "password" and "password confirmation" fields, you need to write data received from the provider and indicated in the contract. You must put a mark in Keep Alive. 
VPI and VCI values \u200b\u200bto find out by calling the provider. They must be prescribed in the corresponding fields. 
This operator additionally uses binding to the MAC address of the equipment used. This address is the identifier of the physical device assigned to it during production. Before starting the 2500U setup, you must inform the provider. Address information is located on the DSL modem etiquette located on the bottom of the housing. It is a sequence of 12 digits and Latin letters and marked Mac ID. 
In the absence of an address on the label, the information is present in the extended menu. To do this, click on the "Start" tab (Device info) in the top row. For the version of the router firmware 1.0.50, the physical address is denoted by LAN Mac. 
After filling the necessary fields, click on "Save". The INTERNET indicator on the front panel of the device should light up after saving the configuration on average after 20-30 seconds.
In the WAN tab, select the Home partition, and click Add (Add ") in it. On the Create Connection page, make VPI data, VCI from the Rostelecom Regional Provider, and in the SERVICE CATEGORY column, select UBr without PCR from the list. To continue, you need to click Next. 
On the next page settings, set a mark in PPP Over Ethernet and click Next.
After that, the PPP UserName and PPP PSSWORD fields are required to make information about the user name and password from the contract. And also note Keep-Alive. The last action saves the connection in case of accidental disappearance and subsequent recovery. Then click Next to go to a new page. 
Here, check items: Enable Nat, Enable Firewall, Enable Wan Service. On the last service item to write Rostelecom. 
After clicking on Next, go to the page with final information. After checking it, the values \u200b\u200bentered earlier click Finish. Now there is an opportunity to control the signaling about the connection on the Internet DSL front panel internet indicator.
Bole detail we disassembled settings in the article
"Beeline"
This operator assumes the use of the WAN-connections L2TP hardware. The following types of compounds are specified in the current modem of 2500U in technical specifications:
- PPPOA.
- PPPoe.
- IPOA.
- IPOE.
The connection of the Beeline operator for the DSL router is not provided. It is supported by the manufacturer "D-Link" in the models of later release, for example, DIR-300.
NetBynet.
On the main page of the interface, in its menu, the transition to the connection settings is made by selecting the WAN tab, and in it - the Home section. The connection is created by clicking on Add. The new page allows you to select the type of connection from the contract. The 200500U modem under consideration is available PPPOE type connection when you receive a network address automatically and PPPoE with a static address received from the provider.
In both options, the username and password are present in the subscriber's contract. They must be prescribed into the appropriate fields. The entered password must be confirmed in the corresponding field. 
After that, it is required to note the item "Cloning Address". At the same time, the provider will see the MAC address of the computer, with which the DSL modem works. In the mode selection field, Always is prescribed ("Always"). In this case, the connection will be stable with possible failures on the communication line. Entering is completed by pressing NEXT stencil.
The new page requires to make items: Enable Firewall, Enable Nat. 
In the case of a PPPoE connection with a local (static) IP address, you need to additionally mark the STATIC IP item. 
At the same time, after clicking NEXT, a page will open, where you must fill in the data fields from the contract: the address assigned to the provider, the subnet mask used by the gateway, preferred and alternative address of the DNS servers.
The entered information is saved after clicking on the Save Settings key. On the next page, you need to check the data-reflected data on it. In the case of their correct values, press FINISH stencil. After a while - no more than 20-30 seconds - the Internet indicator on the front panel of the 2500U router should turn around, which will confirm the presence of a connection with the provider.
Mode of work Bridge
With the listed providers, the DSL modem works only in the router modes and a transparent bridge. Repeater modes (repeater), amplifier, adapter, or access point to it are not available.
If when set up and saved settings you need to use a 2500U modem in the bridge mode, it will not cause difficulties. To do this, go to the "Configure Manual" tab by clicking on it the cursor. On the Jump page to the WAN section, and in it - the HOME subsection. In the created connection, adjust its type: PPPoE to Bridge, leaving the remaining settings unchanged. 
Additionally added "type of encapsulation" and service category. For the first parameter, Bridged IP Over ATM LLC SNAP is selected, and for the second - UBR.
In the last step, press FINISH stencil. After such a change, the DSL router performs only the function of transferring information from the telephone line to the computer and in the opposite direction.
In the bridge mode, the 2500U router only works with one computer in the general case. But the DSL model under consideration initially has only one LAN connector. The built-in firewall stops working. Protection against network attacks takes on a computer. Network address translation (NAT) and printer stops working.
IPTV.
For the television console required for the operation of interactive television, it is necessary to highlight a separate LAN port. IPTV receives a flow of information directly from the provider. On other router models, the dedicated port is translated into a transparent bridge mode and can no longer be used for other purposes. The modem 2500U has only one LAN port and the consumer has to be addressed about the priority connection. The question concerns the change in settings.
The BRIDGE connection is required for IPTV. It is necessary in the WAN section to specify the values \u200b\u200bof the VPI and VCI parameters from the contract. 
In the "Other" settings section, mark the "Enable IGMP" item. After that, the port "Got" for IPTV. 
Parental control
This setting is an addition to the main functions of 2500U. On the Administration page, click on the "Configure Manual" tab. In the top menu of the open tabs, select "Control", click on it. 
After clicking on "Add" the ability to create a new rule appears. The local network for the DSL modem under consideration consists of only one computer, so the rule is created only one.
It indicates the MAC address of the PC, an arbitrary name is prescribed and a mark is set to "Included". After that, a schedule is drawn up, where the days of the week, the clock, minutes of the beginning and end of the possibility of work are included. 
In the "URL-filter" section, you can prohibit / enable the work of the site specified sites. Port 80 is selected. The settings are completed by clicking on "Save". 
Dynamic DNS.
The setting in the DSL of this parameter refers to the extended version of the routing settings. Access is made by clicking on the "Advanced" tab. Dynamic DNS (DDNS) enters work in dynamic IP mode, allowing each address change - in digital form - leave a permanent domain name. 
Security settings (antivirus, firewall) on a modem 2500U
Access to security settings In the DSL modem is provided from the main menu when the "Firewall" tab is selected. Here are the rules of IP filtering of dangerous and working addresses. To create a new rule, you must click on the stencil "Add". Here are also created virtual servers and DMZ zones (Virtual Server DMZ). They are capable of redirecting all Internet traffic to a specific IP address on the local network. 
Possible malfunctions and ways to eliminate them
All problems arising from the operation of DSL routers model 2500U are divided into the following groups:
- consumer equipment software;
- hardware system;
- malfunctions arising from the service provider.
In the first case, it is necessary to share situations when they occur at the initial stage of configuration, and the failures that appear during the operation of the DSL modem. At the initial stage, the 2500U configuration is required with accurate observance of all the requirements of the manual, the sequence of operations, saving the entered data at each stage. After the DSL configuration process is completed, you must check the resulting final indicators.
Causes of emerging failures during operation of 2500U are often external factors: sudden races of supply voltage or thunderstorms. Great assistance in these cases will be used by uninterruptible power supply (UPS) with an autonomous rechargeable battery (AKB). If it is impossible to continue the DSL operation, you must reset the 2500U settings to the factory values. And also work to restore the data entered earlier. Great help will be firmware equipment to the latest version of software.
In the search for the hardware fault ("iron") will help the DSL modem indication on the front panel. The exception is a situation where the Power LED is not lit. For this option, it is useful to replacing the voltage adapter of the AC network. It is necessary to check the condition of the wires and measure the voltage using the multimeter. It will be useful to study all cable connectors for their reliable connection and verify the service life of the system communication lines. In the absence of Internet information, the PC is sometimes "to blame". If you can check this version, it can be replaced for a while.
After the test activities carried out, the service consumer needs to call the technical support of the operator and report the problem. In the case of normal operation of the provider equipment, assistance is required for warranty or repair shops.
DSL router firmware update
Update the 2500U router, that is, the version of its software is required when accumulating numerous problems. Before starting the DSL firmware, you need to carefully examine the stickers on the body of the product, to determine the version of its hardware (H / W) or the type of revision. As well as the software version (S / W) at the time of release. The S / W version or line type is: Annex A, Annex B. A revision - A, C, D. 
The site www.dlink.ru you need to download the latest file with the BIN extension to the latest time from the Firmware folder, save it on your computer. 
On the main page of the interface, go to the "System" tab. To select "Update software" item, on the new page, click the "Overview" button. After finding the downloaded file, click the "Update" button to install the new on the 2500U router. At the end of the update process, the computer will automatically reboot and return to the factory settings. It is necessary to re-configure the DSL router according to the technology outlined above. 
Reset Routher 2500U settings to factory
The DSL modem provides hardware and software discharges. For the hardware return of the 2500U router settings to the factory values, the RESET button has been recessed into a narrow socket. Its subtle rod should be press and hold for 10-15 seconds. After that, you need to wait for a flashing stop for a minute. Factory values \u200b\u200bwill be restored. 
For software reset at 2500U, it is required after logging in to the Administration page, click on the "Configure Manual" tab. On the new page, bring the cursor to the inscription "System" in the upper right corner, click it and select "Factory Settings". By clicking on the item, run the process of restoring the initial values \u200b\u200bwith the subsequent automatic reboot of the DSL router. 
Output
The D-LINK DSL-2500U router review shows that the model is used where there are only ADSL telephone lines, which can be used with satisfactory speed. DSL is a budgetary entry level. On its basis it is impossible to organize a local network. Here the principle of "modem one - computer one" is valid. The history of the modem of 2500U has more than 10 years. DSL rightfully earned the "deserved pension".
pros
DSL's positive qualities include:
- 2500u has a relatively easy setting process with the possibility of rapid return to source values \u200b\u200bin case of an error;
- ability to use DSL in telephone lines with a large level of interference;
- the presence of a large base of components for the repair of the device.
Minuses
The negative qualities of 2500U today are considered:
- no wireless communication module, USB connector;
- the presence of only one network port;
- outdated element base, leading to frequent failures;
- low data exchange rate on the network.
At home, I use home Internet using ADSL technology via D-Link modem. I will say that access to the Internet does not differ reliability. I do not know who more blame: either provider; either a modem with a link line; Or maybe the user is to blame :). Only I always noticed that when working the modem heats up very much. Thoughts to disassemble him and somehow improving the cooling of a very warm element arose a long time ago, and somehow all the hands did not reach. And once, a spring day, I disassembled him. 
Included, in a disassembled form, looked at the twenty online video minutes, began to grope hot elements. The culprit of global warming has found immediately, this is a large bg (chip). 
After her palpation, the index finger burned down. That is, in fact, the whole modem together with the case is heated only from her. On the reverse side, at the location of the chip, detected a darkening of the printed circuit board. 
Although I know that the working temperature of some radio elements is satisfied large, and the temperature of 70-105 ° is a normal phenomenon, I waited for me a poor thing and all her surroundings, so I decided to hoist the radiator on it. The appropriate radiator found on the old motherboard from the computer, which was glued to the microcircuit. 
With the help of a screwdriver, the radiator was selected in the legitimate owner. He decided to place a modem on the microcircuit using a thermal oil. Step-storey, I found the thermoclast only in the telemaster, gave 150 rubles for him. 
Thermocles in our small town, the thing is very rare, so immediately developed a spare option: glue the radiator on superclauses, applying it (small points) on the four corners of the chip, the center of the Majm thermal CCT-8, which is sold in each computer store for 30 rubles. 
It is important to calculate everything correctly so that the paste spread over the microcircuit does not mix with the superclaim. Since the radiator did not completely hurt, to the place intended for him, it had to trim it. 
In my case, the placement of a whole radiator interfered the screen of another, large chip (not heated), and on exactly the same friend's modem, this screen was absent, so I glued the radiator completely. For gluing the radiator, we applied a thin layer glue on the microcircuit, pre-degreasing the surface. 
We press the radiator to the chip, and a bit of it is driven from side to the side, which would be a layer of glue evenly and thinner. 
Thinking, I decided to glue and the remaining part of the radiator. It is glued to the screen, and the edges of the main radiator, aligning them. Maybe the heat transfer will be small, but worse will not be accurate. 
This was convinced of the heating of his small part and the screen. According to the instructions, the drying time of the adhesive is 24 hours, but if you do not move the radiator, then the product can be used before, because glue is quite thick and not even drying, keeps well. We collect a modem and know: overheating Now we definitely do not threaten. Well, and naturally, we note the speed and stability of the Internet connections in the time :).
