Beginning next year, the American Federation of Television & Radio Artists will begin a two-tier system regulating how it offers health benefits to members.As of Jan. 1, 1994, members earning $ 7,500-$ 15,000 annually will be eligible for either an individual plan, which will not include dental coverage, or a costlier new family plan. With earnings of more than $ 15,000 a year, members are automatically enrolled in the family plan. Members who have earned enough to be fully enrolled for the past 10 years will be automatically enrolled in the family plan for up to three years. Those members who earn between $ 7,500 and $ 15,000 and opt for the individual plan will not receive medical or dental coverage for dependents. In order to deal with continuing funding crises, health fund trustees also initiated several other measures, including adding a $ 50-a-year deductible when purchasing prescriptions from retail pharmacies, eliminating part of the Medicare reimbursement plan and requiring surviving spouses to continue paying premiums for health coverage once their mate dies. Some measures went into effect this month.