According to the radio industry website, RadioStats ( RadioStats. Net ), WBBM's website as a standalone entitiy was in the past the most visited radio station website in America, though since all of CBS's local sports and news properties were merged into the united CBSChicago. com, figures have not been updated.

In February 1977, Jacobson failed to make WBBM's 10 p. m. newscast because he was being booked at a police station, charged with making an illegal left turn and driving on a suspended license.

In an effort to bolster ratings and improve the respectability of WBBM's newscasts, the station announced in July 2010 that Kurtis and Jacobson would permanently anchor the 6 p. m. newscast on WBBM beginning on September 1.

In 1960, WBBM's McClurg Court studios were the site of the first televised presidential debate between John F. Kennedy and Richard Nixon.

In 2002, Diann Burns, former anchor at WLS-TV and Antonio Mora, news reader from Good Morning America, became WBBM's new main anchor team.

And in the July 2007 ratings period, WBBM's reporting of the Amy Jacobson fiasco resulted in the station's newscasts falling further behind in the Nielsen ratings.

Since August 1, 2011, WBBM's programming has been simulcast over sister station WCFS-FM ( 105. 9 MHz .).

WBBM's main competition is WKSC-FM " 103. 5 Kiss FM ", as well as urban rivals WGCI-FM and WPWX.

He became WBBM's political editor in 1970.

Jacobson left for WFLD in 1993 after a dispute with WBBM's management.

In April 1986, Jacobson got into a shouting match with Ken Boles, a WBBM executive news producer, in a bank near WBBM's studios.

In a landmark case in media law, Jacobson and WBBM's owner, CBS, were found guilty by a federal jury in Chicago in November 1985 of libeling the Brown & Williamson tobacco company in a November 1981 expose in which Jacobson accused the cigarette manufacturer of marketing cigarettes to children and teens.

But during nighttime hours the skywave radiations are reflected from the ionosphere, thereby creating the possibility of one station's rendering service, via skywave, at a much greater distance than it can through its groundwave signal, and at the same time vastly complicating the interference problem because of the still greater distance over which these skywave signals may cause interference to the signals of stations on the same and closely adjacent frequencies.

For this reason, the more uncertain skywave service was denominated `` secondary '' in our rules, as compared to the steadier, more reliable groundwave `` primary service '', and, for both skywave service and skywave interference, signal strength is expressed in terms of percentage of time a particular signal-intensity level is exceeded -- 50 percent of the time for skywave service, 10 percent of the time for skywave interference.

The area covered by a local station at night without significant skywave interference is known as the nighttime interference-free ( NIF ) contour, and is typically specified in mV / m ( signal strength ).

* Cancellation of signal: In addition, many AM stations, including but not limited to the clear channel stations, often experience cancellation of their own signals within the inner and outer fringes of their normal groundwave coverage areas at nighttime due to the stations ' individual skywave signals reaching the listeners ' receivers at or near equal strength to the stations ' individual groundwave signals ; this phenomenon is very similar to the multipath interference experienced on FM Radio in the VHF band within mountainous regions and urban areas due to signals bouncing off of mountains, buildings, and other structures, except that the groundwave-skywave cancellation occurs almost exclusively at nighttime when skywave propagation is present.

As a result of skywave propagation, a broadcast signal from a distant AM broadcasting station at night, a shortwave radio station or ( during sporadic E season ) a low band TV station can sometimes be heard as clearly as local stations.

The lower power, coupled with typical nighttime AM skywave interference, caused the post-sunset signal to be listenable in limited areas of the market, mainly northern Kentucky and the western side of Cincinnati.

The station's skywave signal was recently received in Salt Lake City, Utah.

It was recognized that skywave signals, because of their reflected nature, are of great variability and subject to wide fluctuations in strength.

In 1947, affidavits were filed with the Commission by various clear-channel stations alleging that extensive interference was being caused to the service areas of these stations during daylight hours, from class 2, stations whose signals were being reflected from the ionosphere so as to create skywave intereference.

If a U. S .- based team ( located in either Boston, Chicago, Detroit or New York City ) was playing in Toronto on a particular Saturday night, thousands of fans in the U. S. city whose local team faced the Leafs would often listen to the CBC broadcast via skywave reception, with the game often drawing far more listeners during the HNIC broadcast period than any local station.

Originally, the use of HD Radio transmission on AM was limited to daytime only, and not allowed at night due to potential problems with skywave radio propagation.

One of the problems with providing coverage of an area the size of the UK was installing sufficient DF stations to cover the entire area to receive skywave signals reflected back from the ionised layers in the upper atmosphere.

As this antenna produced large amounts of skywave, the area of undistorted fading-free reception-was in spite of its high transmission power-at night not as large as planned and so it was planned to replace this antenna by an aerial with better skywave surpression.

As this antenna had an unfavorable vertical radiation pattern, which produced much skywave resulting in a too small fading-free reception area at night, in 1934 a new antenna was installed.

It is beamed at 96 degrees ( i. e. east ) and was originally mainly intended for night-time ( skywave ) coverage of Poland, Czechoslovakia, Hungary and the western USSR, key target areas for the BBC during the Cold War.

By night the skywave transmission was helped by extra power sometimes to as high as 150, 000 watts.

With respect to skywave service rendered at night, class 1, -- A stations are the only stations permitted to operate in the United States on clear channels specified for class 1, -- A operation, and so render skywave service free from cochannel interference whereever they may be received ; ;

This is a phenomenon familiar to all radio listeners, resulting from reflection of skywave signals at night from the ionized layer in the upper atmosphere known as the ionosphere.

but during the middle daytime hours these skywave radiations are not reflected in any substantial quantity, and during this portion of the day both skywave service and skywave interference are, in general, negligible.

during the same period around sunrise, skywave transmission is declining, until at about 2 hours after sunrise it reaches a point where it becomes of little practical significance.

With respect to nighttime assignments, the degree of skywave service and interference is determined by skywave curves ( figs. 1 and 2 of sec. 3.190 of the rules ) giving average skywave values.

These curves were derived by an analysis of extensive skywave measurement data.

Some 45 frequencies are assigned for use primarily by dominant Class 1, -- A or Class 1, -- B clear-channel stations, designed to operate with adequate power and to provide service -- both groundwave and ( at night ) skywave -- over large areas and at great distances, being protected against interference to the degree necessary to achieve this objective.

class 1, -- B stations are protected at night to their 0.5-mv./m. 50-percent time skywave contours against cochannel interference.

Since the provision of skywave service requires adequate freedom from interference, only class 1, stations are capable of rendering skywave service.

But nighttime operation by stations of other classes of course entails skywave interference to groundwave service, interference which is substantial unless steps are taken to minimize it.

During nighttime hours, because of the intense skywave propagation then prevailing, no large number of stations can be permitted to operate on one of these channels, if the wide area service for which these frequencies are assigned is to be rendered satisfactorily by the dominant stations which must be relied upon to render it.

In the daytime, on the other hand, since skywave transmission is relatively inefficient, it is possible to assign a substantially larger number of stations on these channels.

His signal was for the other dogs to come running, but it was also the signal for Mama and the other maids to watch out.

We knew the enemy was subdued, because a flare was fired as the signal.

The spectrometer was adjusted to minimize the amount of dispersion mode mixed in with the absorption signal.

This measurement was obtained by W. Blumberg of the University of California, Berkeley, by observing the breadth of the free induction decay signal.

I turned left too soon and got a signal showing that I was still behind him but he was to the right.

After a while the signal became a buzz and I knew he was behind me.

His signal was coming loud and clear and then all of a sudden it turned to a buzz.

There was no word spoken, no apparent signal given.

As if this was a signal, Poet abruptly began to thrash the water and the quick movement slowly made them sink through the water.

And it was clear that Adrien was not mistaken, for both Small and Cromwell took no step toward aiding in the sending up of the new topgallant mast till Philip Spencer had given the signal to obey.

His election was the signal for seven southern slave states to declare their secession from the Union and form the Confederacy.

When the Israelites, led by Joshua toward the Promised Land, arrived at the banks of the River Jordan, the Ark was carried in the lead preceding the people and was the signal for their advance ( Joshua 3: 3, 6 ).

Historically, before the advent of widespread digital technology, ASP was the only method by which to manipulate a signal.

When analog television was developed, no affordable technology for storing any video signals existed ; the luminance signal has to be generated and transmitted at the same time at which it is displayed on the CRT.

It was observed that E. coli deprived of glucose produce cAMP that serves as an internal signal to activate expression of genes for importing and metabolizing other sugars.

The Amir had scarcely suppressed it by winning a desperate battle when Abdur Rahman's reappearance in the north was a signal for a mutiny of the troops stationed in those parts and a gathering of armed bands to his standard.

The Amir Sher Ali marched up against them from Kandahar ; but in the battle that ensued at Sheikhabad on May 10, he was deserted by a large body of his troops, and after his signal defeat Abdur Rahman released his father, Afzul Khan, from prison in Ghazni, and installed him upon the throne as Amir of Afghanistan.