Washington ? A stack of old television sets towered above Tim Webster as he put his own dust-covered, 20-year-old set onto the heap. He had replaced it with a new flat-screen TV and decided it was time to part with his old living-room companion.

Recycling centers and landfills across the country are preparing for a surge of unwanted sets in coming months. Next February, most TV broadcasts will be available only in digital form. As a result, sets that rely on antennas to receive over-the-air analog signals will no longer work on their own. At the same time, prices of digital TV sets continue to drop, luring consumers to upgrade.

“The question is what happens to all the TVs people are getting rid of,” said Barbara Kyle, national coordinator for the Electronics TakeBack Coalition, which runs a campaign urging electronics manufacturers to collect old TV sets from consumers and recycle them for free.

Last year, about 68 million TVs were thrown out, given away or recycled, according to the Consumer Electronics Association’s estimates. That number could grow this year: About 14 million households rely on over-the-air broadcasts, according to the Nielsen Co.

Tossing the old TV isn’t an analog user’s only option. Consumers can purchase converter boxes, which generally cost $40 to $100, to translate the digital signal back to analog, allowing people to keep using their current sets. They can apply for government-sponsored cou-pons worth $40 to help pay for the converters. Subscribers to cable or satellite services will not have to do anything to continue watching TV on older analog sets.

Webster said he considered getting a converter box for his old TV but instead decided to spring for a digital set because the prices have become more affordable.

He was one of hundreds of Arlington residents who dropped off a total of 16,500 pounds of discarded TVs for recycling April 19 at Thomas Jefferson Middle School. The county, which holds recycling events twice a year to collect electronics, household hazardous waste and other hard-to-dispose-of items, took in a record number of TVs to be dismantled and recycled.

Electronics pose environmental threats because they contain hazardous chemicals, including mercury in batteries, cadmium in displays and toxins in circuit boards. Old-style TVs and computer monitors with cathode ray tubes, or CRTs, contain between four and eight pounds of lead. Environmentalists say such substances can be harmful when buried in landfills, potentially leaching toxins into groundwater supplies.

Many municipalities have set up recycling sites and hold events specifically geared toward electronics, including cell phones, computers, stereos and VCRs. Bulky TVs are not always accepted, partly because they are more expensive to transport and recycle. Consumers often have to pay a fee of $10 to $50 to recycle a TV, which creates an economic incentive for them to toss it into the landfill.