Cable Systems

WJZ (Channel 13) made a flurry of 11th-hour deals last night to guarantee that it would stay on all Baltimore-area cable systems for at least 60 days.But subscribers in Cambridge will find that Maryland's most popular TV station and all its ABC programs are missing in action today when they turn on their cable TV.And there's more bad news for cable subscribers in Cambridge: WMAR (Channel 2) and all its NBC programs are going to be missing as well. Marcus Cable in Cambridge said it would pull the plug on WJZ and WMAR as of 12:01 this morning, immediately after the midnight deadline mandated by the Cable TV Act of 1992.

A live concert Sunday night featuring singer Whitney Houston welcoming American sailors home from the Persian Gulf can be seen by most cable subscribers, following a decision by the HBO premium service carrying the concert to open its signal to non- subscribers."

Mid-Atlantic Cable agreed last week to extend cable access to more communities in western Howard County by the end of June, ending a wait of more than 18 months for some communities, said James O'Connor, the county's cable administrator.The company will build cable systems to serve residents of more than 20 communities, including Clearview Estates, Chapel Woods and Ashleigh Knolls in Clarksville; Amberwoods in Sykesville; Timberleigh Village, Foxmoor and Florence Farms in Woodbine; and Maryvale Court in Ellicott City.

Comcast Cable Communications Inc. has leased a newly built office building in White Marsh, more than doubling the amount of space in its regional headquarters there, the company and its developer, Nottingham Properties Inc., announced yesterday. Comcast needs the new 75,000-square-foot Class A, or top-tier, building to accommodate growth of the company, which recently expanded its service area. Comcast Corp., Comcast Cable's parent company, announced last month that it had completed a multimillion-dollar acquisition of AT&T cable systems that added 600,000 customers.

A locally produced two-hour comedy special to benefit Maryland's homeless will air tomorrow night at 8 on 18 state cable systems from Allegany to Worcester counties."

Cable television companies and their equipment suppliers are on the verge of installing new technology that will pack many more channels into cable networks, creating a potential programming revolution with implications for broadcasters, telephone companies and the consumer electronics industry.Some cable programmers are getting ready to take advantage of the technique, known as digital compression.Home Box Office began market tests last year in which it is offering three programs at once.

When you pay anywhere from $165,000 to $1 million for a ne condominium at one of Baltimore's most prestigious high-rise addresses, you expect more than rabbit-ears on your television.But the television system the first buyers at Harbor Court, a high-rise west of the Inner Harbor, discovered when they moved seven years ago was only a little better than that.Wired to conventional antennas on the roof, it offered only broadcast stations from Baltimore and Washington, plus a single premium movie channel furnished free by the Harbor Court Hotel next door.

NEW YORK -- Changes in the telephone and cable television industries are gaining a critical momentum that could soon see the two businesses offering consumers everything from ordinary telephone services to dial-up football games.The rate of change quickened Tuesday when the Southwestern Bell Corp. announced it was buying two Washington-area cable television systems. For the first time, a telephone company will be operatinga television company, a move that analysts believe will hasten the union of industries.

WMAR (Channel 2) and its NBC programs were back on cable TV in Cambridge yesterday afternoon.But there was no "Home Improvement" last night as WJZ (Channel 13) and its ABC lineup remained off Marcus Cable following an Oct. 6 deadline for cable systems to get permission from local stations to carry their programs."We're still talking," Marcellus Alexander, general manager of WJZ, said yesterday. "But we're still not on in Cambridge, and I don't know when we will be. We think the offer we initially made was fair."

The 1992 Cable TV Act, intended by Congress to reduce cable television rates, has left area cable television subscribers generally confused and angered by changes in services and rates, judging from dozens of responses telephoned to SUNDIAL, The Sun's information service.The majority of callers responding last Thursday and Friday to a request for comments expressed concerns about rate changes, service deficiencies and uncertainty about what broadcast stations may continue to be carried on cable systems.