Scheme of a soldering station.  Homemade soldering stations

Several technologies are used to create permanent connections. One of them is soldering. It is distinguished from traditional welding by low temperatures, the connection between them is performed using a special material - solder. In the process of soldering, molten solder is applied to the parts to be joined, as it cools, it hardens and the workpieces are interconnected.

Soldering is performed using various devices - an electric soldering iron, a soldering station, etc.

Principle of operation and general characteristics

A soldering station, and sometimes it is called a machine or installation, is a device that is widely used in everyday life, and in electronics, and electrical engineering. The main purpose of this equipment is group or single soldering of parts.

This equipment includes the following components:

1. A control unit that controls the operating parameters of the device.
2. Soldering iron for soldering.
3. Tweezers involved in the assembly / disassembly of elements installed on a printed circuit board.
4. Hairdryer, which is designed to heat the assembly place. It can be used to perform both single and group operations.
5. The heat source used to heat the printed circuit board to a process-defined temperature.
6. A device for removing excess tin.
7. Auxiliary equipment - stands, etc.
8. Bracelets that relieve static stress.

The simplest stations include soldering irons, a control device, and soldering iron stands. The key difference between a station with a hairdryer and a traditional soldering iron is that the use of this machine allows you not only to connect parts together, but at the same time optimize the temperature regime. The station includes various devices that not only increase productivity, but also ensure the safety of the worker.

And of course, we must not forget that soldering stations with a hair dryer are equipped with a device for removing static electricity.

The characteristics, as well as the principles of operation of the station with a hairdryer, are not very complicated, and this allows you to build a soldering station with a hairdryer with your own hands.

Recommendations for assembling a homemade soldering station with a hair dryer

The key requirement that can be made to a homemade soldering station with a hair dryer can be formulated as follows - it must provide an air flow heated to a temperature of at least 850 ⁰C. In this case, the power of the heating element in the soldering station should not exceed 2.6 kW.

In addition, all components of this hot air soldering machine should not be expensive and affordable. By the way, household hair dryers do not meet any of these requirements. Most often, home craftsmen tend to make either a manual or a stationary hot air gun.

Oddly enough, a stationary product is easier to assemble. This is due to the following reasons - no one limits the master in overall and weight characteristics. There is no need to manufacture a pistol grip, which is necessary to control the device.

The hot air gun, in a stationary version, works as follows - the heat emitter stands motionless on the desktop, and the part needs to be moved. This solution leads to complications during soldering. To increase the efficiency of soldering, it is advisable to use a hand-held soldering iron (hot air gun). Such a device should be small in size, and it can be operated with unprotected hands.

One of the main questions that a master who decides to assemble a soldering station with his own hands will face is something like what kind of heating tool it is advisable to use. As already noted, the components that make up a household hair dryer do not meet the requirements that apply to devices of this type. Therefore, it is unacceptable to use them when creating a homemade soldering station.

The practice of creating home-made stations suggests that the best option is to independently manufacture a heater from nichrome wire. Its cross section should be in the range from 0.4 to 0.8 mm. At the same time, it must be understood that the use of a wire of a larger cross section will provide a greater margin of power, but it will be quite difficult to obtain the temperature necessary for operation.

By definition, the heater should not be large. To do this, the heating coil should not exceed 4 - 8 mm in outer diameter. As the base on which the heating element will be fixed, it is necessary to use a material with high resistance to high temperatures. It could be ceramic. By the way, a detail of such a plan, installed in a household hair dryer, may well come up.

A small fan can be installed as a supercharger. By the way, it can also be removed from an old hair dryer.

The fan should provide an air flow in the range of 20-30 liters per minute. Another option is an air compressor for aquariums. To improve its performance, it is necessary to supplement it with a receiver. For it, you can use an ordinary plastic bottle.

The manufacture of the case for the hair dryer can be performed based on several options. It is possible to use materials that show high resistance to temperature, such as ceramics, but this solution will lead to an increase in the cost of the structure. You can reduce its cost by using partial thermal insulation of the channel through which hot air moves.

For the case of a self-made hot air gun, you can use the case from a household appliance. There are some conditions - for example, the body must be sufficiently voluminous, and the nozzle must be made of heat-resistant materials or metals.

Another concern that will face the master is to ensure that the device is working. In particular, the design of a home-made device should include a trigger (switch) and an element responsible for adjusting the parameters of the air flow, namely the speed of its movement and its temperature. To solve these problems, rheostats must be installed in the electrical circuit, which allow smooth power adjustment.

The assembly of the product begins with the manufacture of the spiral. When winding it, it must be taken into account that its resistance should be in the region from 75 to 95 ohms. The spiral must be wound on a reliable insulator, and on top it must be closed with an insulator, for example, asbestos or fiberglass. After assembling this knot, the ends of the spiral should come out.

The finished element must be installed in a previously prepared channel of the housing, that is, it must be lined with a layer of thermal insulation. After installing the spiral in place, it can be connected to the power wiring, which includes the switch.

IMPORTANT! When performing work, you must always remember about thermal insulation.

An air heater must be mounted in the back of the housing. If the dimensions of the supercharger do not allow it to be installed in the housing, then it is quite possible to fix it from the outside. An air duct must be connected to supply air.

Terms of Use and Safety

When working, it is necessary to strictly observe the safety precautions and rules for the use of such devices. First, fire safety must be observed.

During operation, it is unacceptable to change the temperature in the heating element abruptly.

During operation, care must be taken not to allow contact with heated elements. It is unacceptable to get moisture on the body and inside the hot air gun.

Nozzles can only be replaced after the hair dryer has cooled down.

The workplace must be well ventilated.

Do-it-yourself soldering station scheme, element base

The key tool of a soldering station is a soldering iron. If, during self-assembly of the station, you can use some elements removed, for example, from household appliances that have served their time. That soldering iron without any disputes should be new. Many craftsmen prefer Solomon products and some others.

After selecting a soldering iron, you can proceed to the selection of a diode bridge for the electrical circuit and transformer. In order to get a voltage of 5 V, a linear regulator with good cooling is needed. As an alternative, you can consider using a transformer that has the windings that are needed to service the digital unit.

A schematic diagram of a home-made device can be searched on specialized forums.

Button assignment and firmware options

On the front panel of the station, control buttons should be installed that are responsible for the following functions:

• Decreasing/increasing the temperature in a certain step, for example 5 or 10 degrees.
• Setting pre-selected modes.

Instead of control buttons, you can use an external device (programmer) or perform firmware inside the circuit. Setting the temperature is pretty easy.

Temperature controller for low voltage soldering irons

Beginners can try their hand at assembling a simplified circuit. In fact, this is the same station, only with limited capabilities. Since it will have a slightly different filling. It can work with 12 volt soldering irons or devices assembled on the basis of a micro soldering iron.

At the heart of such a scheme is the regulator device of the network soldering device. It has 16 levels of temperature settings.

To repair various types of equipment, special equipment is required, which is not so cheap. For this reason, many electronics engineers come up with ways to make a soldering station with a hairdryer with their own hands. It turns out that this device can be built from improvised means. There is nothing particularly difficult in this procedure, and the recommendations below will help determine the best option for the device.

What it is?

The made station with a hair dryer is a special equipment that can be heated to extremely high temperatures, which makes it possible to instantly heat up metal bends. The device has a fairly simple design that allows a novice electrician to understand the unit, not to mention professionals.

It is worth noting that soldering irons are combined with other equipment, which makes it possible to guide the tool as accurately as possible. The unit in question is classified as a semi-professional device. They can perform a number of different tasks, regardless of the level of difficulty.

Differences

Do-it-yourself soldering stations with a hairdryer may differ in some parameters. Among them:

• The size of the working sting.
• Power indicator.
• The performance of the air cooling unit.
• Maximum operating temperature.

The quality of the device depends on these indicators, so they need to be given special attention.

Design

The units under consideration make it possible to melt plastics and metals with a relatively low melting point. The softening of materials is carried out by blowing with a hot heated special spiral. As the main working element, various analogues with a common structure are suitable. For example, a homemade soldering station with a Lukey hair dryer consists of the following parts:

• Body part.
• A heating element.
• Air blower.
• Lever.
• Switch.

Some variations are equipped with an indicator and a regulator of the degree of heating, as well as special nozzles that make it possible to carry out specific work of varying degrees of complexity.

How to make a soldering station with a hairdryer with your own hands from improvised means?

Useless or unnecessary devices and a steel tube can be used as a housing. In the process, the base will be heated to the highest possible temperature. To work with it, wrap the tube with a thermally stable material.

A household hair dryer will serve as the basis for home-made equipment; a spiral acts as a heating element. A constant airflow is provided by a small fan attached to the handle. The spiral is made of which is twisted with a small pitch between the turns. A metal with a low thermal conductivity is suitable as a base. When winding the spiral, make sure that a few centimeters at the base remain free. This part is finished with a heat-resistant fabric to be able to hold the device in your hands. The nozzle is best built from ceramic or porcelain, and an increase in efficiency can be achieved by thermal protection equipment.

Safety

After completing the assembly of the soldering station with a do-it-yourself hairdryer, the design will have a gun configuration. For ease of use, it can be attached to a special holder. For safety reasons, everything must be insulated. At the final stage, the switch is mounted and the mains wire is connected. Then proceed to testing the device. Subject to safety precautions and assembly rules, it will not be difficult to build a structure on your own.

Varieties

How about a hairdryer? First of all, you need to remember that this equipment is divided into two types:

1. Turbine models in which an electric motor is responsible for moving air. This creates a powerful flow.
2. compressor options. Such mechanisms are assembled on the basis of compressors, the air flow in them is more targeted.

By the principle of action, both types are identical and do not differ in any way.

Soldering iron analogue

Alternatively, you can use an old soldering iron for the body of the soldering station with a do-it-yourself hairdryer. First you need to take out all its insides. Be careful not to damage anything. In addition, you will need a 2 kW halogen lamp, which will make a quartz insulator.

With the help of a glass cutter, the ends are cut off, a technological tip is put on the resulting tube on one side, in which a socket is made for the heater. As the last element, a nichrome plate is used, with a thickness of not more than 0.7 mm.

When making your own soldering station with a hairdryer, you should follow a certain sequence:

• The quartz insulator is carefully inserted into the spiral.
• To reduce the heating of the device, the insulator is wrapped with foil.
• The heating element is mounted in the housing and fixed with a wire from the side of the handle.
• A prepared block is also placed there, previously wrapped with an asbestos cord (for convenience and reliability of landing in the nest).
• The air supply hose, located in the handle, is connected to the compressor.

Not only novice radio amateurs, but also experienced craftsmen experience certain difficulties when soldering radio-electronic elements with inexpensive soldering irons without thermal control. After all, you may encounter such a phenomenon as overheating of the tip of the device, which leads to oxidation of the solder, the formation of soot on copper, and as a result to poor thermal contact with tin on the board and the leg of the element, or to excessive heating of the board and peeling off the tracks on it. In this article, we will look at how to make a soldering station with our own hands, providing all the necessary assembly diagrams, photo and video materials.

Step 1 - Making a contact soldering iron

This option can be called the simplest and quite budgetary. This design regulates the voltage on the soldering iron, changing the tip temperature accordingly. But with this method of adjustment, there is no feedback from the tip, that is, we can judge its temperature only by external indicators. However, this significantly improves the quality of soldering. If you plan to connect large parts, then the power supplied to the soldering iron can be increased, if smaller, then reduced, which is very convenient.

We recommend using (dimmer) as a voltage regulator. The only downside to this homemade soldering station idea is that the temperature range is too wide. After all, the power in the dimmer is regulated almost from 0 to the maximum, while we do not need to reduce the power by more than 2 times. But you can redo the circuit, add a "fine-tuning" resistor in addition to the main one.

Soldering station assembly scheme at home:

This circuit uses a rectifier bridge, which will increase the voltage from the standard 220 volts at the input to 310 volts at the output of our homemade soldering station. This will be relevant for those home craftsmen who have an electric one, which is why the soldering iron does not heat up to operating temperature. If there is no dimmer available, you can assemble it yourself, how to do it, and what we need for this, we considered in our article about.

Step 2 - Assemble the air soldering iron

Sometimes when soldering, it becomes necessary to replace SMD elements and a soldering iron with a tip is too large and inconvenient for this. For these purposes, a special air dryer is used. The principle of its operation is similar to a home hair dryer - the air flow is forcibly blown through the heated element and transferred to the place of soldering, heating the solder non-contactly, evenly, and not at one point, but in a certain area.

An air soldering iron can be made from a regular one by inserting an antenna tube that is suitable in size instead of a tip. Next, you need to close all the holes provided for cooling. For example, using heat-resistant paper and a coil of copper wire, as shown in the picture.

Forced air supply occurs with an aquarium compressor, using a dropper tube through the part where the power cord is connected.

To adjust the temperature of the air flow, you can use the dimmer from the previous method. Additionally, it is recommended to rewind the soldering iron to a lower voltage of about 8-15 volts, this will significantly increase the safety of the device due to the absence of life-threatening 220 volts. A nichrome wire with a diameter of 0.8 mm from the electric stove spiral can serve as a heater. It must be carefully wound around the frame without overlaps and short circuits. You need to pay attention that you will also need a step-down power supply, the power of which must be at least 150 watts. A suitable mains transformer can be used as it.

A more expensive method of controlling the temperature at the hot end of a soldering iron is to maintain the set degrees on it. For this, a thermocouple is additionally installed near the sting, in one of our articles we told,.

By combining our homemade products, you can make a universal soldering station that will keep the set temperature, which is very convenient and corresponds to the functionality of expensive purchased models.

Another option is to make a non-contact infrared soldering station from a ceramic lamp socket and a nichrome coil connected to a step-down transformer and a dimmer for easy adjustment. You can also use a thermostat.

You can see how to work with an infrared soldering station in the video below, and also learn about the nuances of working with it:

Overview of homemade products on Arduino

A do-it-yourself soldering station with a hairdryer is a fairly simple but very useful device. With it, you can repair radio components and other products at home. This device will be a worthy replacement for expensive equipment, the purchase of which is not always advisable.

Principle of operation and general description

A soldering station is a special device that has a wide range of applications in electrical engineering. Using this unit, you can carry out individual or group soldering of parts.

A homemade soldering station is able to heat metal bends and plastic to high temperatures. It has a very simple design and principle of operation, so you do not need to be a professional to make it.

Softening of materials occurs by blowing them with hot air. For this, a special heating coil is included in the process. Such devices are characterized by high accuracy in the direction of air masses. Therefore, a do-it-yourself soldering station with a hairdryer can be classified as semi-professional equipment.

Design features

If you decide to create a soldering station with a hairdryer with your own hands, you need to understand its design. Its main components are called:

• Control block. Controls all main operating parameters of the unit;
• soldering iron. Directly involved in the soldering process;
• tweezers. Necessary for assembly and disassembly of parts that are installed on a printed circuit board;
• hairdryer. An important device that heats the nodes that are assembled;
• heat source. Produces thermal energy necessary for the efficient flow of all technological processes;
• a device for removing unwanted tin;
• various auxiliary items;
• bracelets to relieve static voltage.

The most structurally simple soldering units are a set of a soldering iron, a control device and a stand. With the help of such specialized stations, it is possible not only to solder, but also to optimize this workflow as much as possible. They include parts that increase productivity and ensure high safety during operation.

Manufacturing technology of a soldering station from improvised means

A person who has basic knowledge in the field of electrical engineering will be able to assemble a soldering station with his own hands. To do this, follow the simple instructions below.

General requirements for homemade equipment

There are specific requirements for a home-made unit with a hair dryer. It must ensure the creation of a stream of air heated to 850 ° C. The power of the heating element must not exceed 2.6 kW.

When choosing components for the station, it is necessary to give preference to those that are available or are of low cost. Therefore, it is advisable to make a manual or stationary unit with a hairdryer. The latter works in such a way that the emitter of thermal energy is stationary, while the part itself moves. This principle of operation creates certain difficulties in the implementation of soldering.

To increase the efficiency of the work performed, it is advisable to use a manual unit. It has a small size and weight, which makes it easy to operate.

Features of creating a heater

Experts recommend making their own nichrome wire heater. It should have a diameter in the range of 0.4-0.8 mm. It must be understood that a large wire size will give it a huge margin of safety, but it will make it more difficult to achieve the optimum temperature. Therefore, it is not advisable to use too large a thread for this.

The outer diameter of the formed heating coil should be 4-8 mm. To fix the created part, a special base is used, which is resistant to high temperatures. Experts recommend giving preference to ceramics. Such a base can be removed from an ordinary household hair dryer.

Hot air blower forming technology

In order for the created home-made station to work efficiently, it is necessary to equip it with a small fan. It can be removed from an old hair dryer or other unnecessary household appliance. The fan should provide an air flow of 20 l/min.

It is allowed to use an air compressor, which is usually placed on aquariums. To make the unit work more efficiently, it is supplemented with a receiver. For this purpose, you can take a regular plastic bottle.

Shaping the station body with a hair dryer

To create a body of a soldering station, it is necessary to use heat-resistant materials. This can be done in several ways using the following options:

• ceramics. In terms of security, an excellent, but very expensive solution;
• partial thermal insulation of the channel, through which air heated to high temperatures moves;
• old case from any household appliance. It should be voluminous and not subject to destruction from high temperature.

Assembly and maintenance of equipment

In order for the created soldering station to work efficiently, a switch and a device for adjusting the main operating parameters are added to its design. The last unit must set the optimum air temperature and speed of its movement. To achieve this goal, rheostats are included in the equipment. With their help, you can smoothly adjust the power.

The creation of a station must begin with the formation of a spiral. It is wound on a high-quality insulator and covered with fiberglass on top. As a result, the ends of the spiral should come out. The resulting part is placed in a housing with finished thermal insulation. The spiral is subsequently connected to the power wire to which the switch is connected. An air blower is mounted on the back of the case.

What mistakes can be avoided during the build process?

A do-it-yourself soldering station cannot consist only of a heating coil and a fan. This device cannot be made from a simple hair dryer. In this case, he will not be able to melt even tin. Therefore, you should not forget about additional equipment.

In order to increase the heating temperature, it is not necessary to reduce the fan speed and the diameter of the outlet. This will only lead to the melting of the case and the failure of other components of the equipment.

Video: A simple soldering station with a do-it-yourself hairdryer

Soldering stations when working with electrical appliances are simply irreplaceable. The main element of the device is considered to be an inductor. Additionally, some stations have special regulators that allow you to switch the power of the device. The main parameters should include the threshold voltage, as well as the maximum temperature of the power tool.

Depending on the area of ​​​​work, the nozzles of the devices may vary. To date, the most common are considered to be contact and non-contact modifications. You can collect them at home, but you should familiarize yourself with the device of the station in more detail.

Simple station diagram

The soldering station (diagram shown below) includes a high threshold inductor. Regulators, as a rule, are installed of a linear type, but digital analogues can also be found. Modulators for stations are used mainly single-channel. Capacitors are used to change the cutoff frequency of a power tool. Special connectors are installed to connect the power and ground cables. If we talk about contact models, then the devices additionally have impulse blocks. In turn, a contactless soldering station often includes adapters of various types.

Hairdryer device

Assembling a soldering station with a hair dryer is quite simple. Most often, these power tools are used to heat the surface. They are ideal for soldering plastic pipes. First of all, to assemble the device, you need to select a microcircuit that is designed to control the device. Most often in this situation, conventional analogues with the marking PP20 are used. You can buy such chips in the store.

A soldering station with a hairdryer works on phase-type capacitors, and they differ quite a lot in terms of capacity. Next, for assembly, you need to install an inductor next to the microcircuit. It must withstand negative resistance at a maximum level of 2 ohms. All this will allow you to cope with sudden power surges. Connectors must be selected based on the available power cables, as well as grounding. The nozzle is best removed from a broken station.

Infrared (IR) modification

The structure of the infrared soldering station is quite complex. Inductors in this case are suitable only for varicaps. Finding them in our time is not difficult. Modulators for the model are best used two-way. They are designed for three modes. All this, ultimately, will allow you to change the power of the device. Among other things, it is important to take care of finding the indicator. Due to it, it will be possible to monitor how the IR soldering station works. It is more expedient to install the socket on the mains near the inductor.

Hot air stations

In order for a hot air soldering station to work, an inductor with good conductivity is required. The nominal frequency parameter must be at the level of 44 Hz. Additionally, you should choose a high-quality regulator to change the power of the power tool. Contacts are usually used as nozzles. For the stability of the outgoing wave, resistors are usually installed in an orthogonal type.

The transmission width parameter for them reaches an average of 55 microns. In order for the soldering station to work well, the modulator for it is selected based on the type of inductor. If you plan to make a power tool of medium power, then the modulator, as a rule, is used self-regulating. The lining for it is used quite rarely. However, to maintain linearity, many experts advise using special operating blocks. Thus, the heating of the contact occurs quite quickly. The temperature due to this element can be increased to a maximum of 200 degrees.

Thanks to this, working with steel surfaces will become very convenient. It is more expedient to select a multi-system connector for grounding. In this case, the negative resistance parameter should not exceed 44 ohms. Experts do not recommend using three-core cables for supplying electricity. In this regard, it is better to trust the four-core types.

Analog modifications

The analog soldering station has good reviews, and in appearance it is very simple. However, when assembling such devices, you must be very careful. The first step is to calculate the threshold voltage in the system. If you work with conventional inductors, then they can quite successfully cope with electromagnetic oscillations. It is more expedient to select capacitors for analog stations of a grid type. In turn, resistors are often advised to solder only coaxial ones.

Contactless models

Today, a contactless home-made soldering station is in demand. It is most suitable for soldering various plastic surfaces. However, she copes with metal parts quite successfully. The accuracy of work in this case depends on the limiting frequency of the power tool, as well as the diameter of the nozzle. Connectors for these devices are usually used three-electrode.

In turn, capacitorless outputs can be found in our time very rarely. Regulators at stations are usually installed with a capacitive varicap. They deal with low-frequency interference quite simply. However, it should be borne in mind that it is important to mount the coil only on a plastic plate. Thus, current will not pass through the bottom of the device.

contact models

This type of soldering station can only work with high-frequency inductors. Additionally, adapters are used to change the phase in the devices. In this case, the threshold voltage of the power tool can reach 50 V. To solve the problem with distortion, experts advise installing capacitor-free outputs. In turn, the resistors for the station board are selected exclusively of an orthogonal type. All this will allow you to stably maintain the reverse voltage at the output at 30 V.

The power consumption of such devices is on average 2 watts. Modulators are used exclusively magnetic. Their current conductivity parameter is on average 44 microns. The degree of distortion of a power tool will ultimately depend on the rate of current generation. Connectors for the station are often selected on an additional expansion board. The power cable of the device is soldered only near the adapter. The case for the specified device can be completely made independently.

How to make a lead-free soldering station?

To date, many models are produced with inductors, in which tetrodes are installed in a belt type. All this suggests that capacitors for power tools should be selected capacitive. The accuracy of work in this case depends on the nozzle.

If you use a four-wire cable, then the instrument's limiting frequency parameter can be on average at the level of 66 Hz. You can solve the problem with high resistance in the circuit by using pulse resistors. Their conductivity is on average 33 microns. Kenotrons for stations are used quite rarely. However, they can significantly increase the phase change process. The downside in this case is the excessive load on the capacitors.

Combined modifications

The combined type soldering station features high soldering precision. Nowadays, it is in demand, but at home it is quite difficult to make this power tool. First of all, the problem lies in finding a multichannel modulator. Only this type is suitable for power adjustment. Microcircuits, as a rule, are installed with the marking PP21. They can work in half duplex mode.

In order to increase the power of the device, multisystem conductors are used. In such a situation, you can hope for a maximum temperature of 150 degrees. In turn, the intermediate frequency parameter averages 23 Hz. Holders for such devices are attached to two-core cables. The maximum negative resistance they must withstand is 13 ohms.

75 V model

At 75 V, a soldering station (made by yourself) allows you to work with various alloys. It can also be used to heat surfaces. These stations are ideal for working with plastic materials. In order to assemble them yourself, the inductor should be selected with a high threshold voltage parameter. Power tool adapters are rarely used. The case can be made independently, or taken from an outdated broken model. Connectors for the power cable must be non-linear type.

To increase the conductivity of the current in the circuit, many specialists can use broadband transistors. Microcircuits, in turn, can be used in various types. If you assemble medium power devices, then synchronous capacitors can be used. Their capacitance usually reaches 15 pF. Inductors with optocouplers are rarely used. This is due to the fact that they have a short lifespan. The phase of the output signal of the devices depends on the speed of the rectification of the current. When installing connectors, copper semiconductors are used quite often.

100 V station

A 100V soldering station (made by hand) is most suitable for working with steel surfaces. At the same time, they also cope well with aluminum. The inductor for such devices is selected with a threshold voltage of about 15 V. Capacitors are most often used multisystem. It is quite rare to meet open-type resistors. In this situation, it is more expedient to think about acquiring cardioid analogues. The minimum current conductivity parameter should be 34 microns.

The degree of distortion in devices depends on the board used. Models marked PP20 are ideal for these stations. However, the modulator for them should be selected separately. Many experts prefer broadband analogues. The maximum negative resistance they can handle is 35 ohms.