Guglielmo Giovanni Maria Marconi, 1st Marquis of Marconi was an Italian inventor and electrical engineer, known for his creation of a practical radio wave-based wireless telegraph system. This led to Marconi being credited as the inventor of radio, and he shared the 1909 Nobel Prize in Physics with Karl Ferdinand Braun "in recognition of their contributions to the development of wireless telegraphy".
A waveguide is a structure that guides waves, such as electromagnetic waves or sound, with minimal loss of energy by restricting the transmission of energy to one direction. Without the physical constraint of a waveguide, wave intensities decrease according to the inverse square law as they expand into three dimensional space.
A signal generator is one of a class of electronic devices that generates electronic signals with set properties of amplitude, frequency, and wave shape. These generated signals are used as a stimulus for electronic measurements, typically used in designing, testing, troubleshooting, and repairing electronic or electroacoustic devices, though it often has artistic uses as well.
Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around 20 kHz to around 300 GHz. This is roughly between the upper limit of audio frequencies and the lower limit of infrared frequencies; these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range.
Marconi Electronic Systems (MES), or GEC-Marconi as it was until 1998, was the defence arm of General Electric Company (GEC). It was demerged from GEC and bought by British Aerospace (BAe) on 30 November 1999 to form BAE Systems. GEC then renamed itself Marconi plc.
The East of England is one of the nine official regions of England. This region was created in 1994 and was adopted for statistics purposes from 1999. It includes the ceremonial counties of Bedfordshire, Cambridgeshire, Essex, Hertfordshire, Norfolk and Suffolk. Essex has the highest population in the region.
The General Electric Company, or GEC, was a major British industrial conglomerate involved in consumer and defence electronics, communications, and engineering. The company was founded in 1886, was Britain's largest private employer with over 250,000 employees in the 1980s, and at its peak in the 1990s, made profits of over £1 billion a year.
The Plessey Company plc was a British electronics, defence and telecommunications company. It originated in 1917, growing and diversifying into electronics. It expanded after World War II by acquisition of companies and formed overseas companies.
British Thomson-Houston (BTH) was a British engineering and heavy industrial company, based at Rugby, Warwickshire, England, and founded as a subsidiary of the General Electric Company (GE) of Schenectady, New York, United States. They were known primarily for their electrical systems and steam turbines.
Ferranti or Ferranti International plc was a UK electrical engineering and equipment firm that operated for over a century from 1885 until it went bankrupt in 1993. The company was once a constituent of the FTSE 100 Index.
The Marconi Company was a British telecommunications and engineering company that did business under that name from 1963 to 1987. Its roots were in the Wireless Telegraph & Signal Company founded by Italian inventor Guglielmo Marconi in 1897, which underwent several changes in name after mergers and acquisitions. The company was a pioneer of wireless long distance communication and mass media broadcasting, eventually becoming one of the UK's most successful manufacturing companies. In 1999, its defence equipment manufacturing division, Marconi Electronic Systems, merged with British Aerospace (BAe) to form BAE Systems. In 2006, financial difficulties led to the collapse of the remaining company, with the bulk of the business acquired by the Swedish telecommunications company, Ericsson.
Marconi Communications, the former telecommunications arm of Britain's General Electric Company plc (GEC), was founded in August 1998 through the amalgamation of GEC Plessey Telecommunications (GPT) with other GEC subsidiaries: Marconi SpA, GEC Hong Kong, and ATC South Africa.
GEC Plessey Telecommunications (GPT) was a British manufacturer of telecommunications equipment, notably the System X telephone exchange. The company was founded in 1988 as a joint venture between GEC and the British electronics, defence and telecommunications company Plessey. The next year, after a joint holding company of GEC and the German conglomerate Siemens AG acquired Plessey, GPT was converted into a 60/40 GEC/Siemens joint venture. The GPT name ceased to be used in the mid-1990s, and in 1998 the company was amalgamated into Siemens Communications.
Tracor was a major North American defense electronics contractor which was acquired by Marconi Electronic Systems (MES), a subsidiary of General Electric Company plc, in 1998. Following the purchase of MES by British Aerospace in November 1999 to form BAE Systems, Tracor became BAE Systems Integrated Defense Solutions. Following a 2005 reorganisation, the company became BAE Systems Sensor Integration, part of Electronics and Integrated Solutions.
Thales Underwater Systems (TUS), formerly known as Thomson Marconi Sonar, is an international defence manufacturer specialising in sonar systems for submarines, surface warships, and aircraft as well as communications masts and systems for submarines. TUS is a subsidiary of Thales Naval, part of the Thales Group, and has sites in the United Kingdom, France, and Australia. TUS is made up of three subsidiary companies: TUS Ltd. in the UK, TUS SAS in France and TUS Pty. in Australia, but it operates as a single company with headquarters in southern France. TUS had annual sales of €400 million in 2006 and employed around 2,100 people.
A comb generator is a signal generator that produces multiple harmonics of its input signal. The appearance of the output at the spectrum analyzer screen, resembling teeth of a comb, gave the device its name.
A network analyzer is an instrument that measures the network parameters of electrical networks. Today, network analyzers commonly measure s–parameters because reflection and transmission of electrical networks are easy to measure at high frequencies, but there are other network parameter sets such as y-parameters, z-parameters, and h-parameters. Network analyzers are often used to characterize two-port networks such as amplifiers and filters, but they can be used on networks with an arbitrary number of ports.
A wobbulator is an electronic device primarily used for the alignment of receiver or transmitter intermediate frequency strips. It is usually used in conjunction with an oscilloscope, to enable a visual representation of a receiver's passband to be seen, hence simplifying alignment; it was used to tune early consumer AM radios. The term "wobbulator" is a portmanteau of wobble and oscillator. A "wobbulator" is a generic term for the swept-output RF oscillator described above, a frequency-modulated oscillator, also called a "sweep generator" by most professional electronics engineers and technicians. A wobbulator was used in some old microwave signal generators to create what amounted to frequency modulation. It physically altered the size of the klystron cavity, therefore changing the frequency.
Aeroflex Inc. was an American company which produced test equipment, RF and microwave integrated circuits, components and systems used for wireless communications. Its headquarters were located in Plainview, New York. In May 2014, Aeroflex was acquired by the UK aerospace company Cobham for $1.46 billion.
Two-tone testing is a means of testing electronic components and systems, particularly radio systems, for intermodulation distortion. It consists of simultaneously injecting two sinusoidal signals of different frequencies (tones) into the component or system. Intermodulation distortion usually occurs in active components like amplifiers, but can also occur in some circumstances in passive items such as cable connectors, especially at high power.
