Morning disc jockey Ross Brittain, host of The Breakfast Club on WOGL-FM (98.1), is expected to sign off for the last time at the oldies hits CBS radio station on Friday, according to sources inside and outside of CBS.

Brittain's departure seems to be part of a shake-up of on-air talent at CBS radio and TV stations in the Philadelphia market as new top management takes control of the media outlets.

WOGL - which competes for the Philadelphia market's top position with WBEB-FM (101.1) - recently laid off Bob Charger as its nighttime radio jock.

Brittain could not be reached for comment, but insiders say his leaving has been described as a retirement.

Meanwhile, David Yadgaroff has been promoted to head the six Philadelphia CBS radio stations. He replaces Marc Rayfield, senior vice president and Philadelphia market manager for CBS radio, who has been promoted to oversee seven New York CBS radio stations.

Wednesday was Rayfield's last day as the Philadelphia market manager. He declined to comment in a phone call Wednesday on the personnel changes.

WOGL's Nielsen ratings have stayed constant throughout the quarter, with the station pulling in top numbers in the market for May and trailing just WBEB-FM (More FM) in April and June.

There has been speculation that CBS is seeking to cut costs at the radio stations to sell them, CBS insiders say.

Separately, CBS3 fired three of its top TV personalities earlier this month: nighttime anchor Chris May, meteorologist Kathy Orr, and sports anchor Beasley Reece. Meteorologist Carol Erickson also left voluntarily.

CBS3's group firing of May, Orr, and Reece appears unprecedented in recent times for a Philadelphia TV station and occurred only hours before the anchors were to appear on camera.

CBS3's new general manager, Brien Kennedy, came to the Philadelphia TV station earlier this year with a mandate to boost ratings, and the firings are viewed as part of his plan to find new - and perhaps younger - viewers.

CBS3's nighttime newscasts substantially trail market leader 6ABC and could fall further behind No. 2-rated NBC10, which is owned by Comcast Corp. through NBCUniversal. The company has been investing in its local news stations to boost ratings and news coverage.

A top CBS official who asked not to be identified said there was no connection between the on-air changes at the CBS-owned radio and television stations.