computer hardware, electronic components, consumer electronics  
Modems (modulator/demodulators) are telecommunication devices used as discrete computer peripherals that interface a host device such as a personal computer (PC), with an external broadband gateway or access network such as provided by a cable television or telecom company. Modems enable information to be transferred over telephone lines or other communication links. The modem translates between characters of PC data and electrical signals which are carried on the phone lines and thus enables the PC to communicate with the external world. Many of the functions that a modem performs are accomplished via software running on a digital signal processor (DSP). In a typical configuration, a modem such as a digital subscriber line (DSL) or cable modem interfaces to a PC via a peripheral component interconnect (PCI) slot associated with the PC. Digital and analog modems are typically treated as two different communication devices and thus have been designed on separate platforms. Dial-up 56 Kbps analog modems over regular telephone lines are not fast enough for today's broadband multi-media content. High speed Internet connections to homes and small businesses have only recently become more commonplace. Technologies such as ISDN (integrated services digital network), cable modems, satellite, and DSL (digital subscriber line) have been in application in replacement of analog modems. ISDN has a maximum speed of 128 Kbps. ADSL (Asymmetric digital subscriber line) is the most widely deployed form of DSL technology. ADSL is becoming more prominent and may soon be the platform of choice for data connections. ADSL uses line-adaptive modulation and provides data speeds from 1.5Mbps to 9Mbps downstream (to the subscriber) and from 16Kbps to 800Kbps upstream. Cable modems are used to provide internet access over cable TV networks and require that the networks are upgraded for two way transmission. A cable modem can transfer data at 500 kbps or higher. A cable modem device is equipped on its back with a radio-frequency (RF) coaxial connector for connection to a CATV trunk line, an Ethernet connector or jack for connection to a PC or the like, a universal serial bus (USB) connector or jack, a reset switch to return the modem to its initial state, and a power supply connector to receive electric power.

Listings on Computers : Networking devices : Modems

  • AMASS Data Technologies Inc
    Designs, develops and manufactures microprocessor-based distributed control modules for the industrial control marketplace and data acquisition systems & related sensors for the environment. Products include environmental modem, radio modems, shaft encoders, data loggers, and embedded control digital I/O module. USA.
  • Best Data Products, Inc.
    Manufacturing an extensive line of data communications products including analog modems, broadband products, cable modems, wireless home networking products, DSL modems and routers, and other digital products for home and office use. USA.
  • Cermetek Microelectronics, Inc.
    Manufactures a broad line of internet appliance modems, high speed modems, low speed modems, data access arrangement, evaluation kits, modem components and telephone line interfaces for the data communications industry. USA.
  • Conexant Systems, Inc.
    Manufactures host-controlled modems, controller-based modems, soft modems, fax modems, DSL modems, accelity CPE, cable modems, direct broadcast satellite (DBS) RF tuner, QPSK demodulator ICs, single-chip coded orthogonal frequency division multiplex (COFDM) demodulator/decoder solution, and home network processors. USA.
  • Data-Linc Group
    Manufactures the broadest line of industrial modems for a wide range of data communication solutions, including wireless serial and ethernet radio modems, dial-up/leased line and frequency shift key (FSK) modems, fiber optic modems, power line carrier modems, and other other special purpose modems. USA.
  • Dataforth Corporation
    Manufacturer of electronic data acquisition, signal conditioning, and data communication products including analog signal filter, butterworth filter, fiber optic converter, galvanic Isolator, isolation amplifier, limited distance modem, thermocouple amplifier , and temperature transmitter. USA.
  • ELPRO Technologies
    Provides a broad range of wireless products and systems for process and manufacturing applications, including wireless I/O, wireless gateway, radio modem, wireless input device, radio bands, wireless PLC interface, and wireless ethernet modems.
  • Multi-Tech Systems, Inc.
    Manufacturer of telephony, Internet, remote access, and device networking products, including voice/fax over IP gateways, turnkey fax servers, external wireless modems, corporate data/fax modems, desktop ISDN modems, external device servers, rackmount modems, embedded device networking products, and remote access products. USA.
  • Netopia, Inc.
    Offers carrier-class wired and wireless modems, routers, and gateways. Featured products include residential gateways, smart modems, parental controls gateways, business routers and gateways, point-of-sale (POS) router, hot spot gateways, and 3-D reach wireless adapters.
  • RAD Data Communications
    Manufacturer of fixed and mobile network access equipment, covering a diverse set of voice and data applications for carriers, service providers and enterprises. Products include miniature modems, rate and interface converters, ethernet access devices, TDMoIP gateways, compressed voice system, and integrated access devices. Israel.

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2009 Electronics manufacturers directory • (Modems section) • Site map