Thermal shrink.

A heat-shrinkable tube of a certain type, color, diameter and thickness is used as insulation in the manufacture of cables.

Two or three-layer thermal insulation technology can be used. With this method, it became possible to combine different types of heat shrink and a combination of different colors!

Managed to pick up transparent heat shrink option, which is very soft and elastic. When using two or more layers of thermal insulation, the microphone effect can be noticeably reduced!

Hence, the most stylish, beautiful and most popular option is the headphone cable in transparent performance, especially when it emphasizes the nobility of copper and silver. During use, the transparent color may fade, especially when worn under clothing.

The advantage of using heat shrink is the possibility of “restoring” the cable in case of careless handling (tears, scratches, etc.), up to the complete “unraveling-weaving” of the entire cable. The heat-shrinkable tube can withstand the ability to shrink and straighten when heated many times over.

Also, heat shrinkage has an operating temperature range from -55 °C to +125 °C, which does not lead to to hardening cable in the cold (and over time it even becomes softer).

Teflon insulation.

Also, FUM Teflon tape can be used as conductor insulation and then “retracted” into general heat shrinkage. This option is relevant when the cable needs to be made as thin and soft as possible.

Winding Teflon tape onto copper or silver lay is a rather labor-intensive process that requires accuracy and patience.

Kevlar thread.

Almost all manufacturers of headphone cables always mention the presence of Kevlar threads or something similar for the strength and durability of the cable, but sometimes they are silent about the number of cores and their thickness.

As a result, the cable appears intact and the thread is intact, but the conductor itself inside the braid is frayed or even rotted, and there is no signal or it disappears. Even when sound is present, it can already pass through only one thin vein remaining alive; here there is no need to talk about any acceptable sound quality.

Therefore, when making my cables, I try to focus on more the amount of the conductor itself, rather than for additional cable break protection. Although, for example, a lay of 34 copper strands with a diameter of only 0.06 mm is not so easy to break (it’s like in the parable of “the twig and the broom”), not to mention when the copper or silver twist is also insulated . Various versions of combined Hybrid cables (silver + copper) are generally unrivaled in terms of tensile strength.

It is also possible to use special additional braid to a ready-made cable (all or partly up to the jack). This is especially true for stationary headphones, various interconnects and adapters, where the thickness of the cable does not play a special role, but additional protection and a beautiful aesthetic appearance do!

BTEs and wires behind the ears.

Many replacement cables have built-in wires that allow them to accept and remember the shape of your ear for a more comfortable wearing and fit of the headphones.

With this method of wearing, the microphone effect may be practically absent.

There are problems that with frequent bending and extension, the built-in wire cannot withstand the load and breaks inside the cable. In this case, you can try to remove the broken wire, and sometimes you even have to replace the connectors themselves with new ones.

In my cables I use more than thin(and accordingly softer) wire, which twists along the spiral of the conductors themselves, as if “merging” with them and becoming almost invisible. With this method, the “survivability” of the ear wire increases significantly, and allows for more flexible adjust the cable to your ears.

Also, instead of a wire behind the ear, heat shrink (one or two layers) can be used again on top of the cable itself. With this option, just warm it up slightly (preferably with a hot air gun, but you can also use steam, or with a regular lighter, but not too much) and give the earhooks the desired shape.

Headphone connectors.

The main problem with many connectors (those that are inserted into the headphones themselves) is loose contact with the sockets of the headphones themselves, which can cause signal loss. And the most dangerous thing is that if the cable is loosely connected to the headphone sockets, they can be accidentally dropped or even lost!This mainly applies to connectors like Westone and Ultimate Ears...

You can try to solve this problem as follows:

When making (turning) master connectors yourself pins are being done with reserve, and then with a fine-grained file or sandpaper customized for specific sockets of the headphones themselves (the main thing is not to remove excess). Sometimes this also applies to factory connectors, which may initially have a larger pin diameter than necessary;

If the connectors have nothing left to grind off, then you can try them increase using solder (preferably containing silver);

Instead of solder (or as an addition), you can use a thin silver-plated wire, a piece of which is placed in the sockets under the connectors, the excess is cut off, and then the cable itself is inserted;

Another method associated with bending the pins of connectors (pins) certain way.

Another personal development: instead of solder, conductive glue “Kontaktol” with silver is applied to the pins of the connectors, after which it is allowed to dry for about a day and you can use it. Of course, if you frequently remove the cable from the headphones, the layer of glue will wear off, but this glue has very low resistance, and when installed in the headphone jacks, it will still fill micropores, thereby improving the signal conductivity characteristics.

For reference: d pin diameter for Westone - 0.78mm, for Ultimate Ears- 0.75mm

Jackie.

Of the variety of jacks for portable devices, the most popular and convenient is the jack angular forms.But here, alas, the choice is small (unlike direct options):

Neutrik NTP3RC, Neutrik NTP3RC-B

There is no one universal technology for cutting fiber optic cables for installation. Each coupling has its own specifics, which are specified in the instructions for it. It may be necessary to completely cut off the Kevlar threads or, on the contrary, leave them and clamp them in the fastener, cut off the power element or, conversely, provide its sufficient length.

General advice is to be sure to follow the prescribed length of the fibers released during cutting, and not to make them too short. Otherwise, installation difficulties will arise.

Moreover, each stage of cable cutting has its own practical nuances - that’s what we’ll talk about today. Let's start with the tools that are used by professional fiber optic installers and solders.

Optical cable cutting tools

The main arsenal of a fiber optic network installer-splitter for cable cutting:

• Stripper knife;
• Stripper-clothespin;
• D-Gel hydrophobic grease solvent;
• Pliers;
• Dummy knife.

As well as side cutters, zip ties, an alcohol bottle, screwdrivers and other tools. There are special suitcase sets for sale for working with optics, for example NIM-25:

Cutting and installation of optical cable into the coupling in stages.

The first thing to do if the cable has been stored for a long time in a humid environment without waterproofing the end is cut off and discard about 1 meter of cable. Optical fiber and other structural elements lose their quality when exposed to moisture for a long time.

This is especially true for optical cables reinforced with Kevlar threads. They perfectly absorb and “transmit” moisture over many meters. Subsequently, if such a cable is laid next to high-voltage lines, the moisture in the Kevlar will become a conductor of current and ultimately cause cable damage.

Outer sheath and cable

To cut the outer sheath, we use a stripper knife - either a standard one for fiber optics, or one that is used for cutting power cables. We set the required thickness of the cut, fasten the knife to the cable and turn it around its axis several times (5-10). This makes a circular cut. Now we make two longitudinal ones from it towards the end of the cable - and the sheath breaks into 2 halves.

Important:

• The thickness of the cut must be set accurately. If it turns out to be too deep, there is a risk of cutting the optical fibers, or dulling the knife blade on the armor. The most unpleasant thing that can happen here is that after welding and finishing installation in the coupling, you discover that one of the fibers has jumped out of the cable, because was damaged during the cut. If the cut is small, you will have to spend time tearing off the shell.
• When working with different types of cables, always try a cut on the tip of a new cable- to check whether the cut thickness is set correctly.

The suspension cable in figure-of-eight cables is cut with cable cutters, and its sheath is separated from the main cable sheath with a knife.

Cutting armor, corrugated armor and Kevlar

Depending on the type of coupling, Kevlar, corrugated armor or wire armor may not need to be completely cut out, leaving some part for fastening. Also, armor and corrugated armor can be used to ground the cable - you will also need to leave a small section.

Inner shells and hydrophobic impregnation

To cut the inner sheath (not all cables have it) use:

• An ordinary breadboard knife (good experience and dexterity are required, as there is a high risk of damaging modules with optical fiber);
• The same stripper knife as for the outer shell, but set to a different cut thickness. We act very accurately and carefully, because... fiber optic is getting closer;
• Stripper clothespin.

It is best to keep two stripping knives on hand - one with settings for the outer sheath of the cable, the other for a thinner cut of the inner sheath.

Now the installer is left with modules with optical fiber, covered on top with film, interlacing threads and hydrophobe (all this together, or in different combinations). We work with gloves, because hydrophobic lubricant is a very unpleasant liquid that is difficult to wash off your hands.

• A thin film, if any, can be easily cut off with a knife;
• Threads are removed manually or with a special hook, which is found on some models of stripper knives;
• We take napkins, D-Gel liquid (“orange”) - it can be replaced with gasoline (if we work outdoors) and thoroughly clean the modules of everything;
• After general cleaning, we clean each module separately in the same way, and then wipe it with alcohol.

Some people use a faster and “cleaner” method: they do not completely cut the cable down to the modules, clearing only a small area, about half a meter. On him bite the shells of the modules and pull everything together- modules, threads, film, etc. - like a stocking. However, despite all the time savings, this method is fraught with damage to the fibers if the applied force is too great. This is especially dangerous in winter, when the hydrophobic lubricant thickens.

Separating the modules

If the fiber optic cable is monotube and its module is made in the form of a hard plastic tube, a circular cut is made with a small pipe cutter and, carefully, so as not to damage the fibers, the module breaks.

In the case of having several modules, everything is more complicated. Firstly, while you are working with one, you need to hold the others, which are actively reaching under your arms. Secondly, the cable itself is suspended and this is not very convenient. It is best to do this work together.

We cut out the empty stub modules at the root. Modules with optical fiber are bitten with a special module stripper. Again it is very important to choose the correct depth of cut, so what? That's right, fiber optics in close proximity to the tool.

Important:

• There is a special pawl on the module stripper that blocks reverse movement. It often happens that it is triggered just at the moment the module is bitten. You cannot open the stripper back; the only way to release the latch is to bite the module again, which can damage the fibers. Therefore, you need to monitor the position of the locking dog.
• Do not pull modules off the fibers with great force; this can damage them and affect the quality of communication in the future. It is better to release slowly, in parts.

Fiber cleaning

Fibers intended for installation and welding must be perfectly intact and perfectly clean. First, we wipe them in the following sequence:

• Lint-free dry wipes - 3-4 pieces - remove hydrophobe;
• Lint-free wipes moistened with alcohol (ethyl, isopropyl).

In practice, expensive napkins are often replaced with high-quality toilet paper (unscented).

Then the fibers are carefully inspected for integrity. Even if the varnish coating is damaged only slightly - It's better to cut the cable again. The time cost will be much lower than if you have to come back here after a while and repeat the process of splicing the fiber optic cable from start to finish.

Coupling mounting

Before inserting the fiber optic cable into the sleeve, Heat shrink is required(except for those structures where the cable is fixed in damp rubber). This is a polyethylene tube that, under the influence of high temperature, “shrinks” and tightly grips the cable and the coupling pipe. This seals the cable entry. In addition, this is an additional element of fixation.

Shrinkage is done after completion of work, because If something goes wrong during welding, you will not need to waste time removing the frozen film.

Shrinkage can be carried out with a blowtorch, a hair dryer or a gas torch. In practice, it is very convenient to use a design made from a tourist gas can and a small burner.

Reading time: 4 minutes

Kevlar is the name of the trademark of high-strength polymer material (KEVLAR), developed by scientists of the American chemical company DuPont. It has superior strength characteristics to steel, but is much lighter in weight.

Kevlar was invented in 1964 by American chemist Stephanie Louise Kwolek while she was working at DuPont.

By 1971, a group of company scientists managed to refine the material, and its mass production began.

Kevlar is an analogue of SVM and Tvaron (which many do not know), created almost simultaneously in Russia and Europe. But since he was the first, all materials belonging to this group began to be called that way.

Production

Kevlar is available in the following forms:

• technical threads;
• yarn;
• roving;
• fabrics.

It is a crystallizing polymer. It is extracted by polycondensation in solution at low temperatures. Reagents are added to the solution, and the polymer is released from it in the form of a gel or crumb. It is washed, dried and dissolved in acid, then threads and fibers are formed through spinnerets, fed into a precipitation bath, washed and dried again.

Properties of Kevlar

The usual fiber diameter is 1 micron, opaque.

1. The main characteristic of the material is its high mechanical strength. The density and, accordingly, the mass are quite low.
2. Kevlar has tensile strength.
3. Does not burn or melt, has the ability to self-extinguish. Begins to decompose at temperatures above 430 °C. When exposed to high temperatures, it begins to lose strength only over time, not immediately.
4. It is resistant to organic solvents.
5. Has a high elastic modulus.
6. Resistant to corrosion.
7. Under the influence of very low temperatures (cryogenic) it not only does not deteriorate, but also becomes even stronger.
8. Has low electrical conductivity.
9. Cut resistant.

Application

The initial goal of the developers was to create a lightweight but very strong fiber that could be used in the production of tires.

Kevlar fabrics

They are usually produced in the form of fabric in rolls called Kevlar-49. There are also other types:

• Staple Kevlar - short-cut fibers just over six mm long. Strength properties are lost due to cutting, but barrier properties are preserved. Used for the production of yarn, felt and non-woven products with high thermal insulation and vibration insulation properties;

• Flock-Kevlar - crushed fiber (up to 1 mm), used for reinforcing various resins.

Kevlar fabrics also have disadvantages:

• lose strength when abraded;
• destroyed by ultraviolet radiation. Requires special resin coating.

Kevlar protective clothing

The reinforcing properties of Kevlar are used by including it in fabrics from which elements of protective clothing are made: gloves, separate inserts in a suit, knee pads, anti-puncture insoles, sports group clothing - for snowboarding, motorsports, etc. Such fabric becomes resistant to cuts and piercing

Kevlar gloves can protect against cuts from glass, short-term exposure to flames and hot objects, while they are soft, elastic and highly breathable (in appearance they resemble knitted ones) and allow you to work even with the smallest parts, since they do not interfere with the sensitivity of your hands.

Since 1970, the development of puncture-resistant fabric for body armor has been underway, and then the production of lightweight bulletproof body armor made from several layers of Kevlar began. To ensure that the quality of the material does not deteriorate under the influence of water and ultraviolet radiation, Kevlar armor is coated with water-resistant fabric.

They also produce other elements of protection against gunshot and shrapnel damage, for example, in armored vehicles.

Sport equipment

Skis, snowboards, helmets, boats and oars made of Kevlar have very high strength and lightness.

Shipbuilding

Kevlar began to be used in shipbuilding relatively recently - the last two decades. The process of its production is high-tech and quite expensive, so it is used selectively - for finishing the hull at the seams, in the keel part.
Used for the construction of yachts. From this material they are very light, consume less fuel and are able to reach higher speeds.

Find out from the video what Kevlar bags are and whether Kevlar fabric will be damaged by a knife.

Other areas

• Kevlar is used as a reinforcing fiber to give the material strength and lightness. They strengthen the cables by threading a Kevlar thread along the entire length, protecting it from stretching and breaking.
• It is also used for the manufacture of orthopedic prostheses.
• Kevlar ropes are characterized by high strength, low weight, corrosion resistance, and non-electrical conductivity, due to which they are widely used in shipbuilding and the mining industry, where they replace steel cables.
• The strength properties of Kevlar fibers are combined with the heat resistance of carbon to create a hybrid material - carbon-Kevlar. It is used to build boat hulls that can reach high speeds.

Due to its high strength and resistance to external mechanical and chemical influences, Kevlar is widely used in a variety of fields and is recognized as one of the most high-tech modern materials. Read about other high-tech materials.

Any cable can be subject to significant physical stress. This is especially true in cases where communications are laid not indoors, but along the street. Any such single-mode optical cable, the price of which requires significant investment, must have special protection from various atmospheric influences. These include high humidity, sudden temperature changes, and sunlight.

Typically, polyethylene is used as the sheath of fiber optic cables. Of course, it has a lot of advantages, but in terms of strength it often shows itself to be not very good. Therefore, in order to strengthen single-mode and multimode optical cables, their structure is strengthened using power elements. These elements are made from Kevlar, which is known to be extremely durable. This is proven, for example, by the fact that this material is used to make modern body armor. Any reinforced optical cable can withstand significant impact without compromising the integrity of the entire structure and sheath.

Features of strengthening optical cables with Kevlar threads

Kevlar allows you to significantly increase the permissible stretch of the cable. With such amplification, the elongation can reach 1000-2000 N. Most often, this indicator is quite sufficient for any general purpose cable. In other words, reinforcement is advisable not only if there is an optical cable for internal installation, but also for external installation. Reinforcement with Kevlar threads has gained wide popularity due to its high efficiency. It is also worth noting that the threads can intertwine with each other, or they can simply form a dense protective layer. Among other things, they provide a high permissible breaking force. Therefore, any similar single-mode optical cable, the price of which will be higher, can be used even in the most unusual situations. The main thing is to correctly install optical communication cables.

Sometimes the cable is reinforced not only with threads, but also with special rods. They can be metal or dielectric. If a single-mode optical cable has a large number of fibers, then such an additional amplifying element can be located in its center.

Fiber optic cable for indoor installation consists of fiber in a protective braid, is available in various Simplex - Duplex modifications, and is used for digital data transmission. RoHS compliant.
- attenuation: 190 dB/km

- structure: 980/1000
- POF diameter (mm): 1.0x1
- outer diameter along the braid (mm): 2.2 - Simplex
- outer diameter along the braid (mm): 2.2x4.4 - Duplex

Optical fiber cable for internal and external highways consists of fiber in a protective braiding reinforced with Kevlar thread, available in Simplex - Duplex modifications, used for digital data transmission. RoHS compliant.
- attenuation: 190 dB/km
- transmission range: max 70 m.
- structure: 980/1000
- POF diameter (mm): 1.0x1
- outer diameter along the braid (mm): 5.0 - Simplex
- outer diameter along the braid (mm): 6.0 - Duplex
- reinforced inner layer: Kevlar
- operating temperature (ºС): -55 ~ +85

M.O.S.T.（MediaOrientedSystemsTransport） is a high-speed multimedia network technology optimized for the automotive industry. Can be used to work inside or outside the car. A serial data bus using a ring topology and synchronous data transmission for audio, video, voice, and data signals using plastic optical fibers (POF).
- attenuation: 190 dB/km
- transmission range: max 70 m.
- structure: 980/1000
- POF diameter (mm): 1.0x1
- outer diameter along the braid (mm): 2.3 - Simplex
- operating temperature (ºС): -55 ~ +85

Microduct microtubes are made of high-density polyethylene for custom installation of fiber optic cables in new or existing channels. Or for use when fiber optic cable routes need to be quickly rerouted and can be upgraded to accommodate new cable types.

POF connectors - patch cords are used for a wide range of industrial audio/video devices. The products are manufactured using high quality raw materials and materials, widely used for telecommunication data or video system transmission. Connectors, connectors and patch cords are available in various modifications.