I had the following connectors at my disposal: a USB socket designed for installation in a printed circuit board and an 80 cm piece of cable with a USB plug at the end.
Initially, I tried to make a flexible extension cord from a 4m AV cable, but the attempt was unsuccessful. When I inserted the flash drive into this cable, the OS "said" that the device is not working properly.
So, it was decided to use a twisted pair cable, especially since I had several pieces of a network Ethernet cable left over from the days of distributing the Internet through a local network. The network cables turned out to be of the lowest quality, since they did not have any screens. Each piece of cable had four twisted pairs in plastic insulation. Judging by the color and hardness of the veins themselves, they were made of some kind of copper alloy, similar to brass.
To transmit the signal and power in the USB2.0 format, at a distance of up to 5 meters, only two twisted pairs are enough. The remaining twisted pairs can be omitted.
However, if the resistance of the cable cores is high, and the device connected to the end of the cable consumes a significant current, then you can start up the power supply via two or even three twisted pairs at once.
Let's take a closer look at this point.
For example, if the current consumed by a USB device is 400mA, and the resistance of one pair is 2 Ohms (both ends), then the resistance of the USB device will be:
5 / 0,4 = 12,5 (Ohm)
In this case, the voltage drop across the cable will be:
5 * 2/ (12,5 + 2) ≈ 0,69 (Volt)
Which, of course, is a bit too much.
But, if you use three pairs at once:
2 / 3 ≈ 0,67 (Volt)
5 * 0,67/ (12,5 + 0,67) ≈ 0,25 (Volt)
Then the voltage drop on the cable will decrease and will no longer be so critical.
About pinout (pinout) of USB plugs and sockets
The picture shows the pinout of the USB 2.0 socket and plug.
Any of the four available twisted pairs can be used to transfer data (+ Data and –Data).
To connect the power, you can use any of the three remaining twisted pairs or all three pairs connected in parallel.
How to secure a USB jack to a rigid network cable
The assembly of my cable was somewhat complicated due to the fact that I had at my disposal not a USB cable socket, but a socket for printed circuit boards.
I had to first isolate the contacts from the back of the case.
And then from the bottom wall of the case (shown in the photo above).
For a not very rigid cable, for example, consisting of only two twisted pairs, you can use this method of attaching the socket to the cable.
First, using sewing threads, we attach a piece of PVC tube (cambric) to the cable. The end of the thread can be secured with molten rosin. We make two longitudinal cuts on the cambric and cable insulation.
It should look something like this. The formed "petals" should be arranged in the form of a cross.
You can then solder the ends of the twisted pairs to the corresponding pins.
We attach the "petals" to the body of the nest with sewing threads. We fix the end of the thread with rosin.
Now you can refine the nest by putting on a heat shrink tubing or covering it with plastic (from a pistol).
But, I only had a very rigid cable, so the mount had to be made more serious.
First, I wound a copper wire with a diameter of 1.3 mm around the end of the cable. Then I soldered the ends of this wire to the side walls of the USB socket.
To give additional rigidity to the structure, I covered the junction of the cable with the USB socket with low-temperature hot melt glue.
To give a more fine-looking shape and improve the appearance of the connector, I covered it with a heat-shrink tube. V
Attention! During the shrinking of the tube, hot melt glue may seep through the slots and into the interior of the socket. To prevent this, you can insert a spacer between the tube and the housing of the socket, or a plug into the socket. Then you don't have to pick out the hot melt glue from the nest.
Content:Working with computer equipment quite often requires any non-standard additional devices. For example, if you have a LAN device, you may need a cable of various lengths with USB connectors. However, standard factory-made products do not always meet the requirements. In such cases, you have to make a USB extension cable yourself.
The principle of operation and scope of USB extenders
To make a normal working extension cord, you need to know well its properties and principle of operation. Its length primarily depends on this. Everyone knows that using a regular cable, it is possible to connect remote devices at a distance of 3-5 meters. These cables are considered passive extension cables, and in many cases, this distance is not sufficient to support normal operation in a home or office. It is not always possible to locate a printer, scanner, and other peripheral devices near the computer.
This problem is successfully solved by an active USB extension cable, which is fundamentally different from a conventional cable. Its beneficial qualities are manifested by active amplifiers built into each end and powered by the USB connectors within 5 volts. Due to this, the useful signal is amplified many times, which makes it possible to connect devices remote from the computer at a distance of 50 meters or more.
In the process of signal transmission, its inevitable weakening occurs. In this regard, for long distances (over 5 meters), only a USB 1.1 connection is used. For distances up to 30 meters, a faster USB 2.0 protocol is required. Of great importance is the cable connecting the devices to each other. It must be of high quality to guarantee the same high connection speed.
The work of the extension cable is carried out independently without any drivers and does not affect the state of the computer in any way. You just need to insert the USB plugs located at the ends of the wire into the corresponding connectors of the connected equipment.
Extension cord making process
It should be noted right away that making a USB extension cord on your own requires special knowledge, practical skills in working with a soldering iron and other power tools. Otherwise, it is recommended to purchase a finished product of the required length, although it will be more expensive than a homemade one. However, many people still try to make a USB extension cable on their own.
First of all, you need to stock up on a standard USB cable of short length. If possible, it should have a ferrite core capable of suppressing high frequency interference and indicating a high quality cable. Such a piece can be requested or purchased inexpensively from people dealing with cable lines. You can also ask them for the required amount of UTP computer cable, preferably one of the higher categories, for example, 5e, 6 or 6e. The speed of the equipment at the opposite end will depend on this.
From the tool, you will need nippers or scissors to cut the cable. performed with a special tool, but in the absence of one, you can do with a simple knife. For the connections, a soldering iron, solder and rosin will be needed, since wire twists are not allowed due to their high resistance. The joints are insulated with heat shrink tubing. You can use duct tape instead.
The work begins with cutting the cables into pieces of the required length and stripping the ends. Insulation is removed from all conductors by about 3-5 mm. USB cable contains 4 conductors, UTP cable - 8. One pair of UTP cable includes two wires - colored and variegated. Instead of a motley one, there may be a white wire. Each pair is soldered to a separate wiring of the USB cable in accordance with the corresponding colors. Do-it-yourself USB extension cable with additional power supply, known as an active extension cable, is made in the same way.
Upon completion of the soldering, it is necessary to check that there are no torn places left. After that, the heat-shrinkable tubes are shifted to the soldering points and heated with a building hairdryer until they completely adhere to the connected conductors. After all the heat shrinkages on the conductors have cooled, they are all collected together in a single bundle, on top of which a common heat shrink tube is installed in the same way. Before connecting the equipment for the first time, it is advisable to check the contacts with a tester. If the check showed the norm, then a homemade extension cord can be used for work.
Twisted pair USB extension cable
Twisted pair extenders are mainly used to connect to the Internet via a 3G modem. These devices are used in dachas and in country houses, in the absence of the possibility of conducting regular cable Internet. Situations often arise when reliable reception of a 3G signal is possible only from a certain place to which a separate cable must be connected. Often, a yusb extension cord of the required size is not on sale, so the only way out is to make it yourself.
For this purpose, you need the right amount of twisted pair, shielded with foil, two USB connectors AM and AF, that is, "male" and "female", heat shrink tubing 16 mm, as well as electrical tape. From the tools you will need a knife, side cutters, a soldering iron, solder and flux.
The manufacturing process begins with pairing and aligning the ends of the twisted pair with side cutters. After that, using a knife, you need to remove from each end the upper sheath of the cable together with the foil at a distance of 1 cm. This operation must be done very carefully so as not to cut the wires located under the sheath. The brown-white and brown wires are cut flush with the sheath as they will not be used in the future. Remove 3 mm of insulating layer from the remaining conductors. The wires are connected as follows: green with orange and green-white with orange-white. The joints are carefully soldered.
The heat-shrink tubing is pre-cut into pieces of 4 cm each and put on a twisted pair. This will allow you to avoid unsoldering the connector in the future. The correctness of the desoldering should be checked very carefully, as accidental confusion can damage the USB device.
After verification, you must turn on the modem in test mode. If the computer does not recognize the device or shows abnormal operation, you need to try a different connector. A lack of a positive result indicates too much current consumption. Since the wires are very thin, the modem simply does not have enough voltage. You may need to shorten the wire until the device starts working or increase the wire size. If the whole system is working properly, it remains to put heat-shrinkable tubes on the connectors and, after warming up, check the quality of the insulation.
I have to travel very often on business trips, I try to take the Internet with me. Of course, it is good when the hotel has wi-fi or a normal 3g signal for a USB modem, but it is not always in the room, then a 5-6 meter twisted pair USB extension cable will come to the rescue.
Preparatory stage: Having looked in a heap of household rubbish, I found a burned-out motherboard from which I carefully dismantled the USB socket with a soldering hairdryer and a piece of cable with a USB plug at the end, left over from previous experiments.
Bad experience in assembling an extension cord: Initially, I tried to connect the USB connectors with a 5m piece of AV cable, but when I inserted the modem, the window said that the device was not working properly. The most interesting thing is that the printer worked quite normally.
Attempt number 2.
Twisted pair USB extension cable
To assemble an extension cord with my own hands, I decided to use a twisted pair cable, especially since I had a lot of Ethernet cable left over from the installation of local networks. The network cables, unfortunately, turned out to be without protective screens and had four twisted pairs in plastic insulation. For signal transmission and power supply of the USB 2.0 standard, at a distance of up to five meters, only two twisted pairs can be used. However, in the case of a 10-meter extension cord, it is better to run power on two or three twisted pairs.
You can read about the pinout of USB plugs and sockets here. To transfer data (+ Data and –Data), you can take any of the available twisted pairs.
For power supply, you can take one or all of the remaining twisted pairs connected in parallel.
Attaching the USB socket to a hard Ethernet cable... First, we insulate the contacts from the back and bottom walls of the case. Then, using sewing threads, we attach a piece of PVC tube or cambric to the cable. We fix the end of the thread with molten rosin or glue. On the cambric and insulation, we make 2 longitudinal cuts. The resulting "petals" should look like a cross. We solder the ends of the twisted pairs to the desired terminals. We attach the "petals" to the socket body with threads. We fix the end of the thread. At the end of the operation, you can refine the USB socket by putting on a heat-shrinkable tube.
For added rigidity, you can wrap a copper wire around the end of the cable. Then solder its ends to the side walls of the socket and cover the junction with low-temperature hot melt glue, and only then heat shrink.
We connect two cables... We cut the ends of the cable and the length with the plug to different lengths to avoid shorting the wires. To reduce the load at the junction, I put the insulation of the network cable on a piece with a plug. The final connection and giving the appropriate look, I make using a heat shrink of a suitable size.
The result of the work can be seen in the topmost photo.
If you assemble a USB extension cable longer than 10-15 meters with your own hands without additional power, then the device connected through it will be unstable. Therefore, it is necessary to use a variant of the extension cable with external power supply. That is, to the red wire (+ 5V) you need to supply + 5V from an external power source, to the black wire, we connect "-".
This version of the scheme is fully operational at distances up to 15 meters.
How to Choose a USB Extender?
Section: Technics and electronics
And so, we have a task - to buy a USB extension cable. Let's say right away that it is very easy to choose such a seemingly complex subject correctly. The main thing is to know the nuances of this choice. Do you want to solve the set problem for "five"? Read the article on TutKnow.ru to the end!
To begin with, let's determine why you need a USB extension cable?
First, let's say right away that this extension cord is not just a cord, but a whole device capable of transporting a port over various distances, for example, between a computer and an external HDD. Are you familiar with the situation when you need to connect a USB flash drive to the USB port on the back of your PC? Have you encountered a short webcam cord? In the first case, you would have to climb under the table when connecting and disconnecting the flash drive. I think such situations arose often.
Making a USB extension cable for 3G / 4G modem
If you use a modem to access the Network, then the presence of a USB extension cable will allow you to amplify the signal by placing the modem, for example, at the cornice. In all such cases, a USB extension cable is the solution to the problem.
I think that a USB extension cable is a really necessary thing, you are convinced. Then all that remains is determine the criteria for its selection.
The only important criterion for choosing a USB extension cable is its length... Among other things, only she is indicated on the package. When purchasing such a device, determine the required extension cord length in advance. Have you identified? Choose a device model with exactly this length or close, but not more. Choosing "forward-looking" will mean throwing away the already purchased extension cord and buying a new one. Why is that? There are concepts such as attenuation. The longer the wire, the higher the attenuation and the lower the data transfer rate. Simply put, in terms of data transfer rate, a meter extension cable will exceed six, and even more so an eight meter.
There is still active USB extension cable, its advantage over the usual one is that it has a built-in USB transceiver, thanks to which it does not reduce the data transmission signal. Such a cable will cost significantly more than a conventional cable.
That's all! Let it be said very little, but it is definitely on the case. All you have to do is find out how long this extension cable is needed and go to a specialized store and buy a USB extension cable. Good luck with your choice!
Tips to help you choose a USB extension cable. What is it for. What is this active USB extension cable and how does it differ from the usual one and what you should pay attention to when buying.
Other interesting articles:
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Diy usb extension cord from twisted pair
High speed connections
There are currently two highly developed #
high-speed serial bus devices: USB and IEEE
1394, also called i.Link
or FireWire. These high speed communication ports are different from standard
parallel and serial ports found in most modern com #
pewters, more opportunities. The advantage of the new ports is that
they can be used as an alternative to SCSI for high-speed peripheral connections #
peripheral devices, as well as connect to them all types of external peripheral devices #
device (i.e., in this case, an attempt was made to combine I / O devices).
Why do you need a serial connection
A new direction in the development of high-speed peripheral buses is
using a consistent architecture.
Twisted Pair USB Extender - An Interesting But Useless Device
To transmit information in parallel
an architecture where bits are transmitted simultaneously requires lines with 8, 16 or more
wires. It can be assumed that at the same time through the parallel channel #
there is more data than serial, but actually increase the skip #
the ability of a serial connection is much lighter than a parallel one.
The serial bus allows 1 bit of data to be transmitted at a time. Thanks to
the absence of delays in data transmission significantly increases the clock frequency.
For example, the maximum baud rate of the parallel EPP / ECP port has reached #
is 2 MB / s, while IEEE # 1394 ports (which use high-speed
serial technology) support data rates of 400Mbps
(about 50 MB / s), i.e. 25 times higher. Data transfer rates of modern interfaces
IEEE # 1394b (FireWire 800) reaches 800 Mbps (or about 100 Mbps), which is 50 times higher than #
increases the baud rate of the parallel port! Finally, the speed of the interface
USB 2.0 reaches 480 Mbps (about 60 Mbps).
Another advantage of sequential data transfer is the ability to
using only one # or two-wire channel, so the interference caused by
transmission are very small, which cannot be said about parallel connection.
The cost of parallel cables is quite high because the wires intended for
for parallel transmission, not only are used in large quantities, but also special #
are stacked to prevent interference, which is very difficult #
capacious and expensive process. In contrast, serial data cables
very cheap, since they consist of several wires and the requirements for their shielding
much lower than those used for parallel connections.
That is why, and also considering the requirements of the external peripheral interface
Plug and Play and the need to eliminate physical port clutter in a portable #
computers, these two high-speed serial buses were developed,
used today. Despite the fact that the IEEE 1394 bus was originally intended #
Chena for highly specialized use (for example, with DV camcorders),
at the moment it is used with other devices, for example, with a professional #
scanners and external hard drives.
Table 8.4. Dependence of the maximum cable length on the resistivity of the wires
Thickness, mm Resistivity, Ohm / m Length (max.), M
28 0,232 0,81
26 0,145 1,31
24 0,091 2,08
22 0,057 3,33
20 0,036 5,00
Parallel connection has a number of disadvantages, one of which is phase #
signal shift, which is why the length of parallel channels, for example SCSI, is limited
(should not exceed 3 m). The problem is that although 8 # and 16 # bit data are #
but they are sent by the transmitter, because # of delays, some bits arrive at the receiver earlier
others. Therefore, the longer the cable, the longer the delay time between the first and #
the last bits arrived at the receiving end.
http://www.megalib.com/books/1617/part.pdf
Not all old tablets support the function of connecting a USB flash drive or modem, but I will tell you how to outwit them and connect a USB flash drive, modem and even a hard drive to them.
Today I want to present to your attention an OTG adapter.
First, I want to tell you what OTG is? This is a way to connect to your tablet or phone that supports OTG function, printer, USB flash drive and even hard drive. This connection is also called USB-host.
You can also connect a keyboard or mouse to your gadget, if the gadget supports this function.
And so, to create this miracle cable, we need:
Old USB extension cable
Micro USB connector (you can get it from a regular USB cable for your device)
Soldering iron and soldering accessories
And so, let's go, in order for us to make such a cable, we will need to connect the 4th pin to the 5th pin of the micro USB connector
We need to get to the fourth contact and connect it with a jumper to the GND wire as shown in the picture.
After we connect the 4th and 5th contacts with a jumper, our gadget will act as an active device and will understand that another passive device is going to be connected to it. Until we put a jumper, the gadget will continue to act as a passive device and will not see your flash drives.
But that's not all, to connect a hard drive to a phone or tablet, this adapter will not be enough for us. To connect devices that have a consumption of more than 100mA, namely 100mA can be supplied by the port of your device, we need to connect an additional power supply to our OTG cable, which should be enough for your hard drive to work.
Here is a diagram of such an adapter
Now it's time to start collecting
We take an old USB extension cable and cut it not too far from the 2.0 connector, since the current is only 100mA to avoid large losses. Cut off at approximately the same place as shown in the photo
After we strip our wire
I connected 4 and 5 contacts with a drop of solder.
Well, here's all our cable assembly
It remains only to check the operability, take the tablet, insert the "adapter" and insert the USB flash drive into it, everything works as the blinking LED on the USB flash drive tells us and the tablet identifying the USB flash drive.
Restrictions:
Old cell phones do not know how to do this.
The flash drive must be formatted in FAT32.
The maximum capacity of a plug-in flash drive is limited by the hardware capabilities of the phone or tablet.
Thank you for your attention!
If you need a USB extension cable for various purposes, then it is not entirely necessary to buy one, especially if you already have a USB socket from something and some old USB plug. Speaking in the vernacular - "papa" and "mama". Well, the connecting cable is not a problem at all: it is inexpensive, and perhaps, again, you have some leftovers. In the end, you can weave thin flexible strands and insert into the same flexible tube. The last version of the cable may even be of better quality than the purchased one.
I even dare to say that such a do-it-yourself USB extension cable is much more pleasant to use, and the manufacturing process brings a lot of satisfaction, you must agree. 🙂
After all, whatever you say, but it’s very nice to use a thing (device, device, gadget), which I made with my own crazy hands! And, besides, you always know how to fix it, change, improve it if something happens.
The main starting elements for the future USB extension cable should look something like the photo on the left: a USB socket and a plug with a piece of wire (the longer the better).
It turned out that with the wires, not everything is as simple as I thought. I wanted to make a sufficiently flexible cable from the audio cable, but the attempt was unsuccessful: after connecting the flash drive to this cable, Windows reported that this device was not working properly.
Therefore, it was decided not to reinvent the wheel, not to experiment, but to go the simplest way and use twisted pairs from the available several pieces of network cable left over from the workers who conducted the Internet to the apartment.
For high-quality signal transmission via a USB extension cable, as well as power supply via USB2.0, two twisted pairs are enough. Those twisted pairs that remain may not even be used. But still, if the cable resistance is too high, and the device connected to the cable consumes a decent current, then in this case, you can connect power to two or even three of these pairs.
Pinout USB sockets and plugs
The photo on the left shows the pinout of the USB socket (top) and USB plug (bottom).
The + Data and –Data data is transmitted over any of the four twisted pairs in the extension cable.
To connect the power, you can also use any of the three remaining pairs, or three pairs by connecting them in parallel.
Securing the USB jack on the network cable
The process is described based on the available USB socket that is soldered into the printed circuit boards.
It is desirable to isolate the contacts from the rear wall of the socket housing.
Also insulate the bottom wall of the case by passing the contacts through the cardboard.
We take a PVC tube, make an incision, put it on the cable. We fasten the tube with ordinary thin threads. By the way, you can not tie the ends of the threads, securing them with a drop of quick-drying glue or even melted rosin.
It turns out like this "flower" with four petals.
Now our pre-prepared petals are applied to the nest and with the same threads are attached to it for a secure attachment.
With a more serious approach to business, you can strengthen the mount by adding rigidity to it, by soldering a wire to the housing of the socket, as in the photo. This will negate the mobility in the area of the connection and the possibility of losing it in the future.
After that, hot glue comes into play. Fans can use epoxy with a filler (for less fluidity), but then the connection becomes in the future non-separable, well, or difficult to disassemble.
Well, for a noble appearance - heat shrink tubing to help you. So that the hot melt glue does not go anywhere during heat shrinkage, you can wrap paper around this place before putting on the heat shrink tube - a kind of thermal insulator.
