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73-598: LBC (originally the London Broadcasting Company ) is a British phone-in and talk radio station owned and operated by Global and based in its headquarters in London. It was the UK's first licensed commercial radio station , and began to broadcast on Monday 8 October 1973, a week ahead of Capital Radio . The launch of LBC also saw the beginning of Independent Radio News broadcasting, as LBC provided

146-452: A personal computer , which also displays on the radio presenter 's screen. A profanity delay is often used to keep profanity and other inappropriate material off the air. For contests , the conversation can be recorded and edited "on the fly", before playback on the air just a few minutes later. Frequency modulation In analog frequency modulation, such as radio broadcasting, of an audio signal representing voice or music,

219-413: A telephone hybrid , which connects the telephone line to the audio console through impedance matching , or more modernly through digital signal processing , which can improve the perceived audio quality of the call. Telephone calls are often organised through a system which also provides broadcast automation , with an administrative assistant answering calls and entering caller information on

292-432: A 2.2 kHz audio tone produces a modulation index of 1.36. Suppose that we limit ourselves to only those sidebands that have a relative amplitude of at least 0.01. Then, examining the chart shows this modulation index will produce three sidebands. These three sidebands, when doubled, gives us (6 × 2.2 kHz) or a 13.2 kHz required bandwidth. A rule of thumb , Carson's rule states that nearly all (≈98 percent) of

365-556: A 47% stake, LBC was sold in 1987, beginning a turbulent commercial history. The new owners were media company Darling Downs, later renamed Crown Communications, owned by Australian entrepreneur David Haynes. Crown sold the station's original base in Gough Square near Fleet Street in the City of London and relocated to Hammersmith ; and in 1989 split the station into two separate services, the news and comment station LBC Crown FM, and

438-622: A BBC 2LO London programme "led to such a rush on the telephones that the Post Office had to intervene". Speech based Talk Radio UK was launched in 1995, with much of its programming featuring phone-ins. It also introduced the notion of the shock jock to the UK, with presenters like Caesar the Geezer and Tommy Boyd constructing heated discussions. Ian Hutchby has researched power relations in phone ins, looking at arguments and confrontations. Using conversation analysis , he describes how

511-443: A baseband modulating signal may be approximated by a sinusoidal continuous wave signal with a frequency f m . This method is also named as single-tone modulation. The integral of such a signal x m ( t ) = c o s ( 2 π f m t ) {\displaystyle x_{m}(t)=cos(2\pi f_{m}t)} is: In this case, the expression for y(t) above simplifies to: where

584-435: A binary signal modulates the carrier, the modulation index is given by: where T s {\displaystyle T_{s}\,} is the symbol period, and f m = 1 2 T s {\displaystyle f_{m}={\frac {1}{2T_{s}}}\,} is used as the highest frequency of the modulating binary waveform by convention, even though it would be more accurate to say it

657-469: A combined weekly audience of 3.8 million, according to RAJAR . Phone-in In broadcasting , a phone-in or call-in is a programme format in which viewers or listeners are invited to air their live comments by telephone , usually in respect of a specific topic selected for discussion on the day of the broadcast. On radio (especially talk radio ), it is common for an entire programme to be dedicated to

730-639: A free catch-up service. In September 2006, LBC 97.3 became available in some other parts of the country on the digital DAB platform, after Chrysalis bought out its partners and closed the Digital News Network rolling news station, which had previously been carried on the MXR multiplex. Each multiplex region − the North West, West Midlands, Yorkshire, North East, South Wales, and the West − broadcast

803-456: A lack of selectivity may cause one station to be overtaken by another on an adjacent channel . Frequency drift was a problem in early (or inexpensive) receivers; inadequate selectivity may affect any tuner. A wideband FM signal can also be used to carry a stereo signal; this is done with multiplexing and demultiplexing before and after the FM process. The FM modulation and demodulation process

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876-406: A phone-in session. On television , phone-in's are often part of a wider discussion programme: a current example in the UK is the "Jeremy Vine" TV show . The concept dates to the early radio era: a December 1924 BBC 5NG Nottingham phone-in programme is described in a 1925 Radio Times article: "listeners ... enjoyed the novelty of hearing their own voices taking part". A prior attempted phone-in to

949-489: A scientific and technical conversation in the Nizhny Novgorod Radio Laboratory , reported about his new method of telephony, based on a change in the period of oscillations. Demonstration of frequency modulation was carried out on the laboratory model. Frequency modulated systems are a widespread and commercially available assistive technology that make speech more understandable by improving

1022-465: A target, its outgoing sounds return as echoes, which are Doppler-shifted upward in frequency. In certain species of bats, which produce constant frequency (CF) echolocation calls, the bats compensate for the Doppler shift by lowering their call frequency as they approach a target. This keeps the returning echo in the same frequency range of the normal echolocation call. This dynamic frequency modulation

1095-470: A tone-modulated FM wave, if the modulation frequency is held constant and the modulation index is increased, the (non-negligible) bandwidth of the FM signal increases but the spacing between spectra remains the same; some spectral components decrease in strength as others increase. If the frequency deviation is held constant and the modulation frequency increased, the spacing between spectra increases. Frequency modulation can be classified as narrowband if

1168-414: A wider signal bandwidth than amplitude modulation by an equivalent modulating signal; this also makes the signal more robust against noise and interference . Frequency modulation is also more robust against signal-amplitude-fading phenomena. As a result, FM was chosen as the modulation standard for high frequency, high fidelity radio transmission, hence the term " FM radio " (although for many years

1241-512: Is called the Doppler Shift Compensation (DSC), and was discovered by Hans Schnitzler in 1968. FM is also used at intermediate frequencies by analog VCR systems (including VHS ) to record the luminance (black and white) portions of the video signal. Commonly, the chrominance component is recorded as a conventional AM signal, using the higher-frequency FM signal as bias . FM is the only feasible method of recording

1314-418: Is identical in stereo and monaural processes. FM is commonly used at VHF radio frequencies for high-fidelity broadcasts of music and speech . In broadcast services, where audio fidelity is important, wideband FM is generally used. Analog TV sound is also broadcast using FM. Narrowband FM is used for voice communications in commercial and amateur radio settings. In two-way radio , narrowband FM (NBFM)

1387-487: Is reduced to an acceptable level. FM is also used at audio frequencies to synthesize sound. This technique, known as FM synthesis , was popularized by early digital synthesizers and became a standard feature in several generations of personal computer sound cards . Edwin Howard Armstrong (1890–1954) was an American electrical engineer who invented wideband frequency modulation (FM) radio. He patented

1460-626: Is that it has a larger signal-to-noise ratio and therefore rejects radio frequency interference better than an equal power amplitude modulation (AM) signal. For this reason, most music is broadcast over FM radio . However, under severe enough multipath conditions it performs much more poorly than AM, with distinct high frequency noise artifacts that are audible with lower volumes and less complex tones. With high enough volume and carrier deviation audio distortion starts to occur that otherwise wouldn't be present without multipath or with an AM signal. Frequency modulation and phase modulation are

1533-405: Is the frequency deviation , which represents the maximum shift away from f c in one direction, assuming x m ( t ) is limited to the range ±1. It is important to realize that this process of integrating the instantaneous frequency to create an instantaneous phase is quite different from what the term "frequency modulation" naively implies, namely directly adding the modulating signal to

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1606-466: Is the Deviation ratio which is the ratio of frequency deviation to highest frequency of modulating non-sinusoidal signal. FM provides improved signal-to-noise ratio (SNR), as compared for example with AM . Compared with an optimum AM scheme, FM typically has poorer SNR below a certain signal level called the noise threshold, but above a higher level – the full improvement or full quieting threshold –

1679-486: Is the Modulation index which is the ratio of frequency deviation to highest frequency in the modulating signal and f m {\displaystyle f_{m}\,} is the highest frequency in the modulating signal. Condition for application of Carson's rule is only sinusoidal signals. For non-sinusoidal signals: where W is the highest frequency in the modulating signal but non-sinusoidal in nature and D

1752-468: Is the highest fundamental of the modulating binary waveform. In the case of digital modulation, the carrier f c {\displaystyle f_{c}\,} is never transmitted. Rather, one of two frequencies is transmitted, either f c + Δ f {\displaystyle f_{c}+\Delta f} or f c − Δ f {\displaystyle f_{c}-\Delta f} , depending on

1825-416: Is used for FM broadcasting , in which music and speech are transmitted with up to 75 kHz deviation from the center frequency and carry audio with up to a 20 kHz bandwidth and subcarriers up to 92 kHz. For the case of a carrier modulated by a single sine wave, the resulting frequency spectrum can be calculated using Bessel functions of the first kind, as a function of the sideband number and

1898-586: Is used to conserve bandwidth for land mobile, marine mobile and other radio services. A high-efficiency radio-frequency switching amplifier can be used to transmit FM signals (and other constant-amplitude signals ). For a given signal strength (measured at the receiver antenna), switching amplifiers use less battery power and typically cost less than a linear amplifier . This gives FM another advantage over other modulation methods requiring linear amplifiers, such as AM and QAM . There are reports that on October 5, 1924, Professor Mikhail A. Bonch-Bruevich , during

1971-536: Is widely used in computer modems such as fax modems , telephone caller ID systems, garage door openers, and other low-frequency transmissions. Radioteletype also uses FSK. Frequency modulation is widely used for FM radio broadcasting . It is also used in telemetry , radar , seismic prospecting, and monitoring newborns for seizures via EEG , two-way radio systems, sound synthesis , magnetic tape-recording systems and some video-transmission systems. In radio transmission, an advantage of frequency modulation

2044-634: The BBC called it "VHF radio" because commercial FM broadcasting uses part of the VHF band – the FM broadcast band ). FM receivers employ a special detector for FM signals and exhibit a phenomenon known as the capture effect , in which the tuner "captures" the stronger of two stations on the same frequency while rejecting the other (compare this with a similar situation on an AM receiver, where both stations can be heard simultaneously). Frequency drift or

2117-481: The City of Prague Philharmonic Orchestra . LBC took up the slot previously occupied by Jazz FM (and briefly Birdsong ), and dropped the "97.3" from the station name to reinforce the notion that it now had national coverage. In a 2023 poll by YouGov , 14% of respondents ranked LBC as a trusted news brand. A further 14% of respondents did not trust LBC. The remaining respondents were either neutral or did not answer. As of December 2023, LBC and LBC London broadcast to

2190-556: The FM band , and the phone-in-driven service London News Talk 1152 on the MW band . These names were simplified slightly in mid-1995 to News 97.3 and News Talk 1152 respectively, but between October 1994 and July 1996 the LBC name was not used on-air at all. Reuters then brought in additional shareholders, and between 1996 and 2002 LBC was part of London News Radio Limited, a company owned jointly by ITN , Daily Mail and General Trust , Reuters, and

2263-405: The FM capture effect removes print-through and pre-echo . A continuous pilot-tone, if added to the signal – as was done on V2000 and many Hi-band formats – can keep mechanical jitter under control and assist timebase correction . These FM systems are unusual, in that they have a ratio of carrier to maximum modulation frequency of less than two; contrast this with FM audio broadcasting, where

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2336-512: The GWR Group . This new consortium revived the LBC name on 1152AM on 1 July 1996. At the end of 1996, the FM service was relaunched as News Direct 97.3FM. Production for the station was moved to the basement of ITN 's multimedia building in Gray's Inn Road . In 2002, the company was bought for £23.5m by the media company Chrysalis , which trumpeted its purchase with the promise that it would lift

2409-475: The breakfast show AM was presented by Bob Holness and Douglas Cameron . LBC's late-evening interview and phone-in programme between 9   p.m. (later 10   p.m.) and 1   a.m. was called Nightline and at various times was hosted by Adrian Love, Robin Houston , Monty Modlyn , Jeremy Beadle and Tommy Boyd . There was also a character called "Mr Nasty" (played by John Forrest ), who argued over

2482-625: The sinusoidal carrier is x c ( t ) = A c cos ⁡ ( 2 π f c t ) {\displaystyle x_{c}(t)=A_{c}\cos(2\pi f_{c}t)\,} , where f c is the carrier's base frequency, and A c is the carrier's amplitude, the modulator combines the carrier with the baseband data signal to get the transmitted signal: where f Δ = K f A m {\displaystyle f_{\Delta }=K_{f}A_{m}} , K f {\displaystyle K_{f}} being

2555-563: The London LBC transmission, augmented with occasional bulletins of regional news and travel information. In February 2007, Chrysalis confirmed media speculation that it was reviewing the entire radio operation at its investors' request. Further media speculation from The Guardian suggested that the group had little option, due to shareholder pressure, to sell its radio arm, including LBC, raising up to £200 million for new acquisitions, while The Daily Telegraph suggested that it could be

2628-755: The SNR is much improved over AM. The improvement depends on modulation level and deviation. For typical voice communications channels, improvements are typically 5–15 dB. FM broadcasting using wider deviation can achieve even greater improvements. Additional techniques, such as pre-emphasis of higher audio frequencies with corresponding de-emphasis in the receiver, are generally used to improve overall SNR in FM circuits. Since FM signals have constant amplitude, FM receivers normally have limiters that remove AM noise, further improving SNR. FM signals can be generated using either direct or indirect frequency modulation: Many FM detector circuits exist. A common method for recovering

2701-457: The amplitude A m {\displaystyle A_{m}\,} of the modulating sinusoid is represented in the peak deviation f Δ = K f A m {\displaystyle f_{\Delta }=K_{f}A_{m}} (see frequency deviation ). The harmonic distribution of a sine wave carrier modulated by such a sinusoidal signal can be represented with Bessel functions ; this provides

2774-494: The audio of the show from his blog, which resulted in its being made available at Wikileaks and elsewhere and the preparation of transcripts of the broadcast. David Aaronovitch in The Times argued for "a class action against LBC for permitting a presenter to inflict her preposterous prejudices on her listeners, to the detriment of someone else's kids." Norman Lamb MP tabled an Early Day Motion criticising Barnett and LBC for

2847-402: The basis for a mathematical understanding of frequency modulation in the frequency domain. As in other modulation systems, the modulation index indicates by how much the modulated variable varies around its unmodulated level. It relates to variations in the carrier frequency : where f m {\displaystyle f_{m}\,} is the highest frequency component present in

2920-405: The binary state 0 or 1 of the modulation signal. If h ≫ 1 {\displaystyle h\gg 1} , the modulation is called wideband FM and its bandwidth is approximately 2 f Δ {\displaystyle 2f_{\Delta }\,} . While wideband FM uses more bandwidth, it can improve the signal-to-noise ratio significantly; for example, doubling

2993-548: The caller he would look into his case personally. It later transpired that the caller was in fact Fathers 4 Justice member Ron Davis, who in May of that year was arrested for entering Parliament and throwing a condom containing purple powder over Blair and nearby Cabinet members. Davis said the attack was in response to the Prime Minister's failure to contact him or look into the matters discussed on LBC 97.3. Mark Flanagan ,

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3066-575: The carrier frequency which would result in a modulated signal that has spurious local minima and maxima that do not correspond to those of the carrier. While most of the energy of the signal is contained within f c ± f Δ , it can be shown by Fourier analysis that a wider range of frequencies is required to precisely represent an FM signal. The frequency spectrum of an actual FM signal has components extending infinitely, although their amplitude decreases and higher-order components are often neglected in practical design problems. Mathematically,

3139-482: The change in the carrier frequency is about the same as the signal frequency, or as wideband if the change in the carrier frequency is much higher (modulation index > 1) than the signal frequency. For example, narrowband FM (NFM) is used for two-way radio systems such as Family Radio Service , in which the carrier is allowed to deviate only 2.5 kHz above and below the center frequency with speech signals of no more than 3.5 kHz bandwidth. Wideband FM

3212-470: The demodulation may be carried out by using the Hilbert transform (implemented as a filter) to recover the instantaneous phase, and thereafter differentiating this phase (using another filter) to recover the instantaneous frequency. Alternatively, a complex mixer followed by a bandpass filter may be used to translate the signal to baseband, and then proceeding as before. When an echolocating bat approaches

3285-470: The frequencies instead to London News Radio , a consortium led by former LBC staff and backed by Guinness Mahon . Staff at the station were in shock, not least because while they had received a tip-off from the Financial Times that they looked set to lose one of their frequencies, they did not expect to lose both. This was one of only a handful of times the UK media regulator had declined to renew

3358-538: The host retains power through devices such as "The Second Position" – the concept of going second in a discussion, giving the host time to formulate a response. Similarly, the last word is always the broadcast word. The public can choose to end the conversation, but they are doing so by withdrawing from the interactional arena (Hutchby, 1996: 94-5; Talbot et al.). In 2007, the BBC suspended all phone-in competitions (but not voting) due to an internal inquiry into corruption in

3431-579: The information signal is through a Foster–Seeley discriminator or ratio detector . A phase-locked loop can be used as an FM demodulator. Slope detection demodulates an FM signal by using a tuned circuit which has its resonant frequency slightly offset from the carrier. As the frequency rises and falls the tuned circuit provides a changing amplitude of response, converting FM to AM. AM receivers may detect some FM transmissions by this means, although it does not provide an efficient means of detection for FM broadcasts. In Software-Defined Radio implementations

3504-464: The instantaneous frequency deviation , i.e. the difference between the frequency of the carrier and its center frequency, has a functional relation to the modulating signal amplitude. Digital data can be encoded and transmitted with a type of frequency modulation known as frequency-shift keying (FSK), in which the instantaneous frequency of the carrier is shifted among a set of frequencies. The frequencies may represent digits, such as '0' and '1'. FSK

3577-470: The licence of an incumbent station. The prospective loss of the franchise brought Chelverton to the brink of collapse, and London News Radio (soon itself taken over by Reuters ) bought LBC to keep it on air until the official handover date of October 1994. London News Radio operated the station from LBC's former studios in Hammersmith as London News 97.3, a rolling news and travel information service on

3650-529: The likely effect of the broadcast on public health. Towards the end of October 2012, the station ceased DAB broadcasts to some parts of the country as regional DAB multiplexes in England and Wales were shut down. Since 2013 LBC has broadcast a consumer law show, called The Consumer Hour that focused on providing information, advice, and support to listeners on various consumer-related topics, such as personal finance, product safety, and consumer rights. The show

3723-481: The listenership to at least one million from around 700,000 (LBC had enjoyed an audience of more than two million in the early 1980s). Production was moved to Chrysalis's base in North Kensington , and the formatting of the two frequencies was swapped, the talk format moving to FM and the news format to AM. On 13 January 2004, then British Prime Minister Tony Blair presented an hour-long phone-in show on

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3796-444: The luminance ("black-and-white") component of video to (and retrieving video from) magnetic tape without distortion; video signals have a large range of frequency components – from a few hertz to several megahertz , too wide for equalizers to work with due to electronic noise below −60  dB . FM also keeps the tape at saturation level, acting as a form of noise reduction ; a limiter can mask variations in playback output, and

3869-402: The modulating signal x m ( t ), and Δ f {\displaystyle \Delta {}f\,} is the peak frequency-deviation – i.e. the maximum deviation of the instantaneous frequency from the carrier frequency. For a sine wave modulation, the modulation index is seen to be the ratio of the peak frequency deviation of the carrier wave to the frequency of

3942-536: The modulating sine wave. If h ≪ 1 {\displaystyle h\ll 1} , the modulation is called narrowband FM (NFM), and its bandwidth is approximately 2 f m {\displaystyle 2f_{m}\,} . Sometimes modulation index h < 0.3 {\displaystyle h<0.3}  is considered NFM and other modulation indices are considered wideband FM (WFM or FM). For digital modulation systems, for example, binary frequency shift keying (BFSK), where

4015-448: The modulation index. The carrier and sideband amplitudes are illustrated for different modulation indices of FM signals. For particular values of the modulation index, the carrier amplitude becomes zero and all the signal power is in the sidebands. Since the sidebands are on both sides of the carrier, their count is doubled, and then multiplied by the modulating frequency to find the bandwidth. For example, 3 kHz deviation modulated by

4088-591: The phone-in London Talkback Radio on AM. The transition was not initially well received, and substantially increased costs, pushing the company into the red. In 1993, the company was sold to Shirley Porter 's Chelverton Investments, after Crown fell into financial difficulties. On the morning of Friday, 3 September 1993, the Radio Authority announced it would not renew the company's two licences, LBC Newstalk and London Talkback Radio, awarding

4161-405: The popular perception that the program is merely an outlet for the angst of serial complainers and housewives while providing entertainment for those who revel in listening to despair and tales of misery delivered the callers. A quality of the show that is frequently satirized is Duffy's seemingly exasperated expressions of despair upon hearing of the plight of a caller. The caller is connected via

4234-505: The power of a frequency-modulated signal lies within a bandwidth B T {\displaystyle B_{T}\,} of: where Δ f {\displaystyle \Delta f\,} , as defined above, is the peak deviation of the instantaneous frequency f ( t ) {\displaystyle f(t)\,} from the center carrier frequency f c {\displaystyle f_{c}} , β {\displaystyle \beta }

4307-547: The production of these games in shows such as charity telethons after a nationwide inquiry into the whole process leading to the cancellation of ITV Play . In Ireland Liveline is a popular afternoon phone in show broadcast by RTÉ Radio 1 that is hosted by Joe Duffy . The phone in program usually focuses on consumer issues, current affairs and complaints from members of the public regarding various issues. The program and its presenter are frequently lampooned by numerous Irish comedians, one being David McSavage , who play on

4380-411: The ratio is around 10,000. Consider, for example, a 6-MHz carrier modulated at a 3.5-MHz rate; by Bessel analysis, the first sidebands are on 9.5 and 2.5 MHz and the second sidebands are on 13 MHz and −1 MHz. The result is a reversed-phase sideband on +1 MHz; on demodulation, this results in unwanted output at 6 – 1 = 5 MHz. The system must be designed so that this unwanted output

4453-619: The regenerative circuit in 1914, the superheterodyne receiver in 1918 and the super-regenerative circuit in 1922. Armstrong presented his paper, "A Method of Reducing Disturbances in Radio Signaling by a System of Frequency Modulation", (which first described FM radio) before the New York section of the Institute of Radio Engineers on November 6, 1935. The paper was published in 1936. As the name implies, wideband FM (WFM) requires

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4526-404: The sensitivity of the frequency modulator and A m {\displaystyle A_{m}} being the amplitude of the modulating signal or baseband signal. In this equation, f ( τ ) {\displaystyle f(\tau )\,} is the instantaneous frequency of the oscillator and f Δ {\displaystyle f_{\Delta }\,}

4599-417: The service to independent local radio stations nationwide. LBC broadcast only to London until 2006, at which time it became available, via digital radio, in some other parts of the country. It has been available nationwide since 2014, with the letters now standing for Leading Britain's Conversation . LBC has a like-branded sister station, LBC News , dedicated to rolling news, travel and weather. The station

4672-575: The signal-to-noise ratio in the user's ear. They are also called auditory trainers , a term which refers to any sound amplification system not classified as a hearing aid . They intensify signal levels from the source by 15 to 20 decibels. FM systems are used by hearing-impaired people as well as children whose listening is affected by disorders such as auditory processing disorder or ADHD . For people with sensorineural hearing loss , FM systems result in better speech perception than hearing aids. They can be coupled with behind-the-ear hearing aids to allow

4745-426: The station's Managing Director, left Chrysalis in 2005 to set up a political consultancy company, and was replaced by David Lloyd. He introduced a podcasting service called LBC Plus, and a number of premium-rate promotional opportunities to replace falling advertising revenues experienced by the radio sector. In January 2006, LBC Plus launched as a paid subscription service providing podcasts ; eventually this became

4818-408: The station, taking pre-booked calls from LBC 97.3 listeners. His appearance was part of the "Big Conversation" initiative to promote government as being more accessible and in touch with the people. During the 10–11   a.m. show, a caller said that he had been denied access to his children for five years and asked what Blair was planning to do about other fathers in a similar situation. Blair assured

4891-619: The subject of a management buyout. Subsequently, it was announced on 25 June 2007 that LBC along with its sister stations The Arrow , Heart , and Galaxy network were to be sold for £170 million to Global Radio by the Chrysalis Group , whose Chrysalis Radio operation closed down. In December 2008 the station moved to the Capital London studios in Leicester Square. In April 2007, a new marketing slogan for (what

4964-566: The telephone with children. Beadle and Forrest went on to star in the Granada Television series Fun Factory . Bob Holness, Douglas Cameron, Peter Allen, Jon Snow, Brian Hayes and Jeremy Beadle, among others, were promoted by Ron Onions , Editorial Director of LBC Radio and IRN 1974–84. Originally owned by a consortium led by the Canadian Selkirk Communications of Vancouver, British Columbia with

5037-459: The two complementary principal methods of angle modulation ; phase modulation is often used as an intermediate step to achieve frequency modulation. These methods contrast with amplitude modulation , in which the amplitude of the carrier wave varies, while the frequency and phase remain constant. If the information to be transmitted (i.e., the baseband signal ) is x m ( t ) {\displaystyle x_{m}(t)} and

5110-434: The value of Δ f {\displaystyle \Delta {}f\,} , while keeping f m {\displaystyle f_{m}} constant, results in an eight-fold improvement in the signal-to-noise ratio. (Compare this with chirp spread spectrum , which uses extremely wide frequency deviations to achieve processing gains comparable to traditional, better-known spread-spectrum modes). With

5183-402: Was initially hosted by Clive Bull with listeners' questions answered by guest consumer lawyer Dean Dunham ; since 2020 Dunham has solely presented the show. On 30 January 2014, LBC announced its intention to begin broadcasting nationally on DAB at 7   a.m. on 11 February 2014 under a new slogan, "Leading Britain's Conversation", with new jingles composed by David Arnold and performed by

5256-476: Was originally based in studios on Gough Square, off Fleet Street in the City of London . David Jessel was LBC's original breakfast presenter; he opened the station just before 6 a.m. on Monday 8 October 1973. The original station had several presenters who became household names in the British media. These include Adrian Love , Jon Snow , Peter Allen , Rosie Boycott , and Bel Mooney . For 10 years from 1975

5329-625: Was then called) LBC 97.3 was introduced − "London's Biggest Conversation", a play on the station's initials. The radio station became involved in the MMR vaccine controversy after a broadcast by Jeni Barnett on 7 January 2009 in which she debated the alleged dangers of MMR vaccine with callers. It became the subject of media controversy, first because her views were criticised as irresponsible by medical journalist Dr Ben Goldacre , and then because LBC and Global Radio threatened legal action against Goldacre for copyright infringement after he refused to remove

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