Results for

Touch panel - Import export

49 Companies

135 Products

Product recommendations

Turkey

France

Germany

Germany

See more products

STIL ELEKTRONIK

Turkey

Stil Elektronik is a leading provider of custom membrane switches and backlit electroluminescent (EL) panels for various industries and applications. With years of experience in printed electronics and HMI design, we specialize in creating innovative and high-quality solutions that meet the unique needs of our customers. Our company exhibits its difference in the market through endless R&D activities, visual and structural presentation of the products, diversifying production, and usage of eco-friendly raw materials. In addition, we take pride in our commitment to sustainability and strive to minimize our environmental impact through our production processes and material choices. Our product range includes: •Graphic Overlay •Membrane switch •Membrane keypad •Membrane keyboard •Capacitive Key Foil •Capacitive membrane switch •Electroluminescent panel, Electroluminescent sheet, Electroluminescent strip •Backlight Membrane Switch •Force Sensor •Seat Force Sensor, Seat Sensor Each product is designed to meet specific requirements and offers unique features and benefits. We work closely with our clients to understand their needs and provide tailored solutions that meet their requirements. We work closely with our clients throughout the process, from concept and design to prototyping and production, to ensure that every product meets their specific requirements and exceeds their expectations. Contact us for more information !

All the products for "touch panel"

Touch Screen Panels

Embossed Graphic Panel

Capacitive Touch Membrane Switch

Website See all products
NORELEM FRANCE

France

Every success story starts with an idea. From standardised components to tooling systems, norelem offers its expertise to meet your machine construction and installation objectives. For over 60 years, we have been constantly developing our product ranges to ensure that each application has its place. Our design office will also help you find the perfect solution for your needs. Norelem also has an established sales network present on five continents, and offers high-quality services: 24-hour delivery, online product availability checks, online shop, technical and commercial hotline in France. Norelem manufactures standard mechanical components.

All the products for "touch panel"

Monitor brackets

Website See all products
PASSTEC GMBH

Germany

Since 1990, PASStec has developed and manufactured innovative electronic components in the field of building and room automation, air-conditioning technology and general control technology. The portfolio includes control panels and gateways for OPC, LON, BACnet and Modbus systems as well as control solutions for DMX-based lighting systems. We also create individual software solutions relating to the aforementioned systems. Technical systems and buildings can be operated, controlled and adjusted efficiently using our TouchLBM control panels. Display sizes ranging from 3“ to 30“ area available. With the TouchMaker project software and other tools, projects can be implemented quickly and easily for these devices. In the field of building automation, the devices are used in office and residential buildings, hospitals and schools. With sicCare, we provide systems for regulating humidity, ventilation and air conditioning in the air-conditioning product segment. SicCare is based on our TouchLBM devices and ensures a better indoor environment. The main aim is to ensure compliance with a given level of humidity. Through slowly adjusted control, this is achieved in a particularly gentle manner for building structures and interior fittings. The system is used in historically valuable buildings such as churches as well as museums, schools, archives, museum warehouses and private homes. We provide customers with products and support worldwide.

Website
KUBOTA BRABENDER TECHNOLOGIE GMBH

Germany

Kubota Brabender Technologie GmbH Kubota Brabender Technologie GmbH is one of the world's leading manufacturers of gravimetric and volumetric feeders for bulk materials such as granulates, powders, liquids, and fibres in all industrial sectors. The company has over 65 years of expertise in the field of high-precision digital weighing technology and has continuously developed and enhanced its universal and special metering systems, controls, and discharge aids. Their broad product portfolio consists of Loss-in-weight-feeders, weigh-belt feeders, single and twin-screw feeders, vibratory tray feeders, bulk bag discharge aids for silos and bins, and bulk ingredient mass flow meters. In 2022, Kubota Brabender Technologie GmbH became a fully owned subsidiary of the Kubota Corporation of Osaka, Japan. Kubota Brabender Technologie offers its technical and consulting services globally through a worldwide network of subsidiaries and representatives.

All the products for "touch panel"

Congrav® OP16-E

Congrav® OP1-S

Operating panel with touch screen - Congrav® OP6-E

Website See all products
NODKA

Netherlands

NODKA was founded in 2001 in Shanghai, China, and now is becoming a leading Chinese industrial solution manufacturer for Industrial Embedded System and Fanless Panel PC products. We offer products and services to over 5, 000 customers in China and more than 30 overseas countries. Our products can be used in industrial automation, home automation, food & chemical industry and transportation, etc. NODKA has 20 branch offices in China and 1 overseas office in the Netherlands which is in charge of European business and technical support, now we have partners in Germany, the Netherlands, Italy, Poland, Singapore, USA, Thailand, Japan, etc., we are looking for more partners all over the world. NODKA has its own R&D team, and one precision sheet machinery factory in Suzhou, China. Besides, we have a lab for initial EMC, Wide Temperature, Vibration, shock and Duration test. As an ISO9001 qualified company, we have got CE, FCC, BIS, CCC certification, good quality comes from rigorous design, constant review and testing, we enjoy to work and study with customers in order to keep improving and making better products, with lot of experiences in development of ODM, OEM products, we can deliver a new design within 45 days. Quality is always the most important thing in NODKA, the products must be burning test for more than 12 hours before shipping, We accept small order and delivery sample within 5 working days, you will find Nodka is a reliable supplier with 2 years warranty.

All the products for "touch panel"

LC270T Panel PC with Operation button (Customized)

WP1501T-R1 | 15" IP69K Stainless Steel Panel PC (Resistive touch)

C2152W-L | 21.5" Touch Monitor (Capacitive)

A2152 | 21.5" Touch Monitor (Resistive)

A082 | 8" Touch Monitor (Resistive)

Website See all products

A page for your business

Can you see this? Your potential clients will too. Join us now so you too can be visible on europages

Add my business

EFCO ELECTRONICS GMBH

Germany

EFCO Electronics GmbH is your trusted partner for innovative industrial computers and intelligent connectivity solutions. Our fanless industrial computers set standards in terms of reliability and performance and are ideal for challenging applications in industrial environments. Our touch panel computers offer intuitive operation and precise control in a manner that is optimised for mechanical engineering and industry. We have a wide range of Teltonika routers, switches and gateways for secure and reliable cloud connectivity. Our 5G routers and LTE routers enable the fast data transfer that is vital for the demands of Industry 4.0 and integrating IoT devices. EFCO Electronics GmbH is not only distinguished by its first-class products, but also by its committed customer service. Our experienced team are here to help develop tailor-made solutions and to ensure that you receive the best possible technological support. You can rely on EFCO Electronics GmbH as your partner for advanced industrial computers, touch panel computers and Teltonika connectivity solutions. Working together, we can shape the future of industrial automation and ensure your seamless integration into the digital world.

Website
CLICKTOUCH

Belgium

ClickTouch is a leading company specializing in the development and production of Human Machine Interfaces (HMI); advanced touch panels, membrane switches, and industrial control panels. The company offers innovative, customer-focused solutions for various sectors, including agriculture, electronics, medical, and industrial markets. ClickTouch is known for its high-quality products that are both technically advanced and user-friendly, striving to meet the specific needs of its customers through customization and reliable technology. The primary activities of ClickTouch include: 1. Design and Development: Creating customized touch solutions and control panels that meet the specific requirements of customers. 2. Production: Manufacturing durable and reliable products using advanced production techniques and high-quality materials. 3. Innovation: Continuously investing in research and development to ensure products stay at the forefront of the market and comply with the latest technological standards. 4. Customer Focus: Collaborating closely with customers to understand their needs and provide solutions that exceed their expectations.

Website
DANNIE.CC TR

Turkey

DANNIE.CC is a global electronics designer and manufacturer founded in 2015. DANNIE.CC aims to create marketable products and services for customers. We do not sell pre-designed devices, we design and manufacture custom electronics. Our main feature is "hardware + software + manufacture" all-in-one approach, which is a unique offer in the market. Among our main solutions are computer vision systems using artificial intelligence algorithms, computers (Corporate compute servers, Corporate storage servers, Communication systems, etc.), payment terms, multi-touch panels, gps trackers, etc. Our production sites are located in Europe, China and Russia. We use the latest ASM, Omron, DEK equipment in production. Our well-developed procurement processes, DFX, MES, quality management systems, - all this allows us to transfer projects to other plants without loss of quality and production speed, if necessary. • 300 000+ Total count of manufactured units • 100+ Products for customers from Russia, Europe and the USA • 50+ Engineers in the team

See all products
CHRIST ELECTRONIC SYSTEMS GMBH

Germany

Christ Electronic Systems GmbH is a leading developer and manufacturer of panel PCs, touch panels and all-in-one plcs. As a subsidiary of Otto Christ AG, we originally started out producing special electronics for car washes. We now sell our products across a wide range of sectors, including mechanical and plant engineering, medical technology, the pharmaceutical and food industry, vehicle construction and agricultural machinery. Our mission is to build reliable, durable and robust devices that perform well in harsh surroundings with high temperature differences or vibration. The development department plays a very important role in our company. Alongside production, it is the heart of our business. This is where we develop innovative new products or design individual equipment in conjunction with our customers to meet their specific requirements. We employ development engineers for hardware and software as well as for mechanical applications, so we can guarantee all-round support for our customers.

All the products for "touch panel"

Industrial VESA Automation

Industrial VESA

Industrial Front Panel

See all products
CINI SP. Z O.O.

Poland

We operate on the market as a manufacturer of electric heaters for radiators and bathroom radiators. All of our heaters are equipped with a thermostat, which allows for precise temperature control. We also have heaters with a touch control panel and a grille. In addition, we offer tees. We conduct wholesale and retail sale. We also provide transport services. We have a large distribution network in our sector. We supply major manufacturers of radiators in Poland, the European Union and overseas. Our offer includes heaters with thermostat type GT. These heaters are used as a complementary element to radiators existing in the central heating system or to heat small heating systems, including bathroom radiators or dryers. They can also be successfully used in other heating systems. However, heaters with electronic GTX thermostats are the result of CINI's previous experience related to many years of activity on the Polish and European heating market. GTX heaters are used for bathroom radiators, dryers and radiators operating in a central heating system. They work very well with stainless steel radiators. Moreover, they are very durable, due to the use of stainless steel heating elements. Heaters with electronic thermostat type QS are very popular. They are used as an intelligent heating element for radiators in the central heating system.

ICP DEUTSCHLAND GMBH

Germany

ICP Deutschland is YOUR partner for Industrial Computer Products of IEI Integration Corp. Our product range covers primarily Industrial Computer Products. These include Touch Panel PCs, All-in-One PC, CPU Boards and Embedded PC. Networking product of ORing Industrial Networking Corp. (Member of IEI Group) and Measurement /Automation products of ICP DAS Co., Ltd. complement our product range. Additionally, we offer all required components such as processors, memory, hard disks, SSD, displays and extension cards to assemble Industrial Computers that are ready-to-operate. Our Products are suitable for long-term usage in harsh environments. Extended Temperature, humidity, dust, shock and vibration are well-known requirements to us. The long time availability of our products offers you planning reliability for your projects. Additionally, our stock in Germany reduces lead times to a minimum. Our experienced staff accompanies you during the entire process of your projects. This starts with information procurement in advance, proceeds with planning, decision making, purchasing and goes as far as service, support and follow-up consulting. We have 20 years of experience in industrial Computer products - take advantage of it!

See all products
HASTELSAN

Turkey

Perimeter security systems in modern production facilities and high-quality products. HASTELSAN, where you can get detailed technical support on panel fence installation, offers products that are common and highly practical to use in farms, military areas, airports or factories. We are here for you to make the most suitable choice for creating safe areas in fields, parks, industrial facilities and sites where many residences meet. During the production of galvanized panel fence, each cutting point and the joints of the wires are produced with our high-tech machines without touching the hand. While the panel fence obtained with the zinc coating method is made, the raw material - the inner metal part that makes up the material, is treated with an average temperature of 433 degrees.Bu çalışmalar sonrasında dayanıklılık en üst seviyeye ulaşmıştır. Taşınması ve montajı oldukça kolay olan ürünlerimiz, mekanik açıdan sağlamdır ve görsel kriterlere uygun olarak üretilmektedir.We have options according to your usage areas and technical support will be provided for your needs. At this stage, correct security expectations are the most important criterion for panel fence selection. Therefore, preliminary evaluation is done in cooperation with HASTELSAN expert team.

Product recommendations

Operating panel with touch screen - Congrav® OP6-E

Germany

See more products

INELCO HUNTER LTD

United Kingdom

Inelco Hunter Ltd is a specialist UK supplier, offering a range of electronic components such as capacitors, relays, displays, touch panels, printers, fans, ESD protection and solutions. Our world class suppliers include Fujitsu, Amphenol, ProTek Devices, Desco and Panasonic. Inelco Hunter is backed by an in-house engineering support team, offering design, consultancy and project management services. Our customers are assured with complete confidence when developing, designing and manufacturing their products.
LAIRDS OF TROON LTD

United Kingdom

Our mission is to make Lairds your preferred partner for exceptional home automation, technology, and entertainment solutions through continuous innovation. Lairds offer world class automation, high-end commercial AV Systems, multi room audio, home theater, lighting and security. Automation and AV technology must be reliable and intuitive. Lairds ensure that our systems are simple but powerful and robust and that it fits your home and lifestyle. Lairds design and install systems for music, video, lights, climate and security. These systems have become more intelligent enabling you to easily operate them from a smart phone, tablet, keypad, or touch panel. Lairds are Scotland’s leading home cinema design and installation specialists, with a passion for perfect systems that you will want to use every day. Lairds have a proven record of accomplishment working with Scotland’s top developers and restaurateurs helping to create the best venues and spaces in the country. From the ultimate in Cinematic experiences and entertainment to security and automation systems, Lairds ensure you have the best. Access live systems information remotely and keep your boat safe from theft, burglary, and vandalism, while you are travelling.
ATS GLOBAL KIOSK

Turkey

Kiosk, Kiosk Türkiye, Kiosk Sistemleri, Kiosk fiyatları, Dokunmatik Kiosk, Kiosk Nedir, Kiosk Sistemi, dokunmatik ekrankiosk systems, touch screen kiosk, touch panel pc, ATM Kiosk Systems, kiosk prices, rental kiosk systems, touch totem systems, touch kiosk production, kiosk manufacturing, ATS Global Interactive kiosks are self-contained computing terminals that provide access to on-demand information and transactions. Some examples include airport self-check-in systems, retail product locators, and bill pay terminals. Other variations include kiosks that rent DVD movies, burn custom CDs and DVDs on demand, or download multimedia files to handheld media players. These systems employ modular hardware designs that can be expanded to include numerous peripherals, such as touchscreens, thermal printers, and card scanners.
ADVANTECH S.R.L.

Romania

ADVANTECH SRL promotes and sells the stock or to order the full range of Advantech products: industrial computers, monitors "touch panel"computers, embedded boards, data acquisition and control systems , industrial communications. The high quality at a competitive price, recommend ADVANTECH products for industrial projects in various fields: transport, telecommunications, heavy industry, food industry., Mining, energy. ADVANTECH SRL designs and manufactures electric actuators and control systems for a variety of industrial processes and equipment in the industry, from ferrous and non-ferrous metallurgy, rolling and wire drawing, electrical wires and steel production, production and processing of plastics, food, handling objects, pumping stations.ADVANTECH SRL take issues of modernization of existing equipment and orders for new equipment based on technical specifications and technology.
QUAD INDUSTRIES

Belgium

Quad Industries is an authority in the manufacture and development of user interfaces and control panels, consisting mainly of capacitive and membrane switches, Piezo touch panels, facing panels, rubber keyboards, PCBs, touch screens and integrated displays, and plastic and metal protective housing. Thanks to its inhouse and external production capacities, Quad Industries is able to assemble these components and make innovative products that are at the cutting edge of progress.
INTRADIS

Czech Rep.

Intradis is involved in design and production of bespoke electronic systems - various control and measurement electronic circuits, security or power saving technologies.Intradis is also a distributor of Programmable Logic Controllers (PLC) and Human Machine Interface (HMI) industrial touch panels manufactured by Wecon.
AVC TECH LTD

United Kingdom

AVC(Advanced Control) technology ltd. is a company designs and manufactures All in one PC(Panel PC), touch screen computer, Industrial PC and touch monitor products. We concentrate to provide customer quality product with up to date technology. We only believe innovation and aggressive attitude can keep us moving forwards.
DHAIMASH LOGISTICS

Finland

Our products are 100% original, brand new and tested. We can supply to wholesalers whole possible kinds of original mobile phone spare parts & accessories with constant availability and wide at competitive prices such as Covers, Flex cables, LCDs, Keypads, speakers, microphones, IC`s, touch panels, ....

WERNE & THIEL SENSORTECHNIC GBR

Germany

As former employees of Armold Automation, which was founded by Gerd Arnold in 1972, in 2002, Walter Werne and Andreas Thiel took over all the areas of the business and these have been continually extended since then. Our company objective is research, innovation and redevelopment, as well as the manufacture of different sensors. Our main products include online moisture measurement systems on the principle of high-frequency capacitance. These measurement systems are used around the world – especially in bulk goods. When used to measure the moisture content in sand, the materials research and testing office at the BAUHAUS UNIVERSITY in WEIMAR (MFPA Weimar) acknowledged in its test report no. B81/1666-03 (dated 15.12.2003) an almost linear probe measurement signal with regard to the moisture content. One of our company's latest innovative products is the OLAS (optical light absorption sensor) turbidity/solids content measurement device, patented worldwide. All products meet the internationally recognised CE standard.

Website
ARCOTEC GMBH

Germany

With almost 50 years’ experience, Arcotec GmbH enjoys success as the sole manufacturer of all three methods of physical pretreatment under atmospheric pressure (corona, plasma, flame). 2019 - With over 45 years’ experience, Arcotec GmbH continues to enjoy success as the sole manufacturer all three methods of physical pretreatment under atmospheric pressure (corona, plasma, flame). Over 15, 000 Arcotec pretreatment systems in use worldwide are a testimony to our consistently high quality and unique know-how in the field of surface pretreatment. 1997 - Introduction of the atmospheric plasma machine (Arcospot®), which distributes high-energy spark discharges. The introduction of the atmospheric plasma machines in particular opened up the market for materials that are difficult to treat at high feed rates. 1991 - Another physical treatment principle, “flame treatment”, was introduced. 1985 - Arcotec GmbH was founded. Pretreatment systems 1976 - Development and deployment of the world’s first plasma machine with open jet electrodes (Arcojet®) for treating plastic moulded parts; this works with electric plasma. Pretreatment systems 1975 - Production of the pretreatment machines begins using high-frequency corona. Pretreatment systems 1974 - Fritz Bloss founded an independent commercial agency.

Website
ADS-TEC INDUSTRIAL IT GMBH

Germany

We believe that a networked future can be achieved if people and machines interact simply and securely. By this, we mean the interaction of people with people, people with machines and machines with machines. For more than 40 years, we have developed and produced industrial PCs and IT systems for the fields of automation, mechanical and systems engineering, logistics, the food, pharmaceutical and chemical industry, the automotive industry and all production industries. Our tried-and-tested IT solutions consist of hardware and software components and provide a comprehensive offer of systems for industrial use. ads-tec Industrial IT GmbH is a wholly-owned subsidiary of ADS-TEC Holding GmbH.

All the products for "touch panel"

OPC9000 series

Website See all products
TEKNOFOAM AKUSTIK IZOLASYON SANAYI VE TICARET LIMITED SIRKETI

Turkey

Welcome to TEKNOFOAM, your premier destination for cutting-edge acoustic solutions and manufacturing excellence in Turkey and the Middle East. We specialize in meeting diverse client needs with a focus on acoustic regulation, project design, and construction acoustics. Our Comprehensive Solutions Include: •Acoustic Sponges •Sound Insulation Foam •Acoustic Floor Coating •Acoustic Tile Carpets •Acoustic Window Coatings •Insulation Materials and many more, which can be discovered on our website! At TeknoFoam, we are dedicated to continuous improvement, infusing our designs with the latest technology and innovation. Our experienced team seamlessly integrates traditional design expertise with a forward-thinking approach. Leveraging state-of-the-art digital design tools, we have upheld a steadfast commitment to evolution since the establishment of our factory. Contact us for further information and discover how TeknoFoam can tailor solutions to meet your specific requirements! Elevate your acoustic experience with TeknoFoam.

All the products for "touch panel"

Tekno Touch Sponge

Fabric Covered Suspended Ceiling Panel

Acoustic Wooden Wall Panel

3D Acoustic Wall Panel

Website See all products
CRYSTAL DISPLAY SYSTEMS LTD

United Kingdom

Who is CDS? Crystal Display Systems is the leading industrial LCD TFT specialist. From ruggedized displays, touchscreens, and interface boards to fully custom monitors and bespoke solutions, our products are used all over the world in a wide range of testing applications. We support customers in retail, gaming, and industrial applications. Why choose CDS? As a manufacturer of industrial displays and touchscreen solutions we are dedicated to quality, reliability, and manufacturing excellence. Our years of experience and research and development allows us to offer high performance display solutions with optimum reliability, whilst remaining cost effective. Where are our displays used? Our displays and touchscreens are built with industrial grade components for optimum reliability to give our clients complete peace of mind. Our solutions are used in a variety of applications including retail, gaming, aerospace, automotive, marine, military, medical, instrumentation, harsh environments, outdoors and more. Where are CDS' customers? Our displays are currently used all over the world, currently in 131 countries and counting! Our diverse range of tried and tested display and touchscreen solutions combined with our product knowledge and project support has given our clients the confidence to use our displays time and time again. With strong shipping links via air, sea, and road we ship direct worldwide. With an unbeatable support team, we are available to customers around the clock.

All the products for "touch panel"

Industrial Panel PC solutions

Ultra-Wide Bar Type Stretched LCD Monitors

See all products
CLASSROOM365

United Kingdom

Classroom365's comprehensive schools IT support and services cater for all educational establishments. We work across London, Kent, Essex and across the home counties. ICT services include supplying and installing interactive displays, WiFi systems, remote backup solutions for business and education, and CCTV security systems. We have a dedicated and experienced team of ICT support technicians and backroom staff who know schools inside and out. If you are in one of the specified EIAs in the UK, then you may be eligible for the Connect the Classroom scheme from the DfE. Please get in touch and see how we can help advise your school.

See all products
YILMAZ MACHINE

Turkey

YILMAZ Machinery is a turkish company specialized in the development and manufacturing of PVC and Aluminum processing machines. We also produce wood cutting machines. Our products are mainly destined to door and window manufacturers as well as furtinure manufacturers. They are sold not only in Turkey but all around the world, and throughout 40 years of experience, we formed solid partnerships with a wide network of distributors. We sell machines and spare parts but we also provide technical support and quality service to help our customers and meet all their needs. Using research and development technologies of suppliers in various sectors such as mechatronics, pneumatics, hydraulics, hydro-pneumatics, we seek to expand our activies and improve our production processes, thus improving the quality of our products. To reach this goal, we are informed about the current developements and use the latest technologies. Our customer-oriented quality management system is ISO 9001 certified and our products meet all international standards regarding safety and quality. You can count on our responsiveness and reliability. Don't hesitate to contact us for more information, we look forward to working with you!

All the products for "touch panel"

SKN 301-451-601 - Digital Roller Conveyor with...

CPM 6161

See all products
AKTAPROM

Ukraine

For many years our company deals with technology of image application upon anodized aluminum with resulting of abrasion resistant surface, different metals engraving, galvanizing etc. During this period our team has presented in a structured fashion all different industrial processes and more to be in one integral unit. This ensures that we are able to take on any order despite its volume and processing complexity. We are ones of leading manufacturers of such ready anodized aluminum products based upon our own Alumaproof technology as: anodized name plates, wall diagrams, face plate for equipment, ID tags, exacting scales, vehicle plates, rating plates, decals, safety labels, prohibition labels, valve control labels etc. Our highly equipped production lines and high quality materials enables us to provide high quality products within short terms upon reasonable prices. Our company is not only a distributor of products, but also direct developer and manufacturer of innovative technologies based upon anodized aluminum and engraving. We are not standing at one achievement, everyday our team tries to improve our product technologies and services. Nowadays, we are implementing advanced technologies in our sphere of production for our clients to get better variants of ready products with reasonable prices.

All the products for "touch panel"

Anodized aluminum control panels

Aluminum push buttons

See all products
C PROX LTD INCLUDING QUANTEK

United Kingdom

C Prox Ltd Including Quantek is a well-known manufacturer of No Touch switches and WC locking systems for automatic and manual doors. They are suppliers of access control, safety systems for gates and doors, automatic door equipment, garage door and roller shutter controls, radio remotes and controls, electromagnetic locks, power supplies, and much more.

All the products for "touch panel"

KROME KIT

Touch For Help Systems

See all products
TOUCH PANEL PRODUCTS LTD

United Kingdom

Control Panels, Manufacture of television and radio transmitters and apparatus for line telephony and line telegraphy