The Manassas Park City Council voted last week to give Virginia Cable Communications, a locally owned company, a 15-year cable television franchise if the city can negotiate a firm financial commitment from the company within 90 days.

Officials of the firm said cable services could be available by March 1984 if Virginia Cable gets the award.

The company has proposed a basic service of 35 channels for $7.95 a month and 54 channels for $9.95. But five major channels would not be included in either package. Residents would have to pay $9.95 each to get Home Box Office, Movie Channel, Disney, Showtime and Cinemax, with a discount for more than one service.

Virginia Cable Communications is a joint venture of Quality Cable Communications Inc., composed of seven Manassas investors, and Enfield Communications Inc., the company that built and operated the Alexandria cable franchise before selling it last year. Quality Cable, headed by three executives from the Manassas-based Merchant Tire Co., has pledged $700,000 toward building the system. Enfield has pledged $300,000.

Two other cable firms that bid on the Manassas Park franchise were ranked as second and third choices by the council, and one of them could get the nod if no agreement is reached with Virginia Cable. Cablevision of Manassas Park Inc. was ranked second and a joint venture between CATV General Corp. and Perry Cablecom, a Connecticut firm, was third.