A 24-HOUR candlelight vigil for the homeless is scheduled to begin Wednesday at 6 a.m. and to end Thursday at 6 a.m. at the Strong Blacks Exhibition and Research Center, 1733 Druid Hill Ave. in Baltimore. Donations of non-perishable food items and blankets are requested. Bea Gaddy, a well-known advocate for the homeless, is scheduled to preside as hostess of the vigil, which will include a breakfast for homeless people on Wednesday. For information, call the center's curator, Darryl Van Carter, at 462-2023 or Bea Gaddy at 563-2749.
* Tickets are no longer available for a musical tribute to King scheduled at 8 p.m. on Wednesday at the Meyerhoff Symphony Hall. The free concert, featuring the Baltimore Symphony Orchestra and Morgan State University Choir, will present works by Ulysses Kay, Antonin Dvorak, Leonard Bernstein and many other composers. The celebration is sponsored by the Maryland Commission on Afro-American History and Culture, the BSO and the Governor's office.
* The third annual Dr. Martin Luther King Jr. Memorial Symposium sponsored by the Oliver Community Association is scheduled Thursday at 7 p.m. at Dr. Bernard Harris Elementary School, at Caroline and Oliver streets. The guest speaker will be Father Maurice Blackwell, pastor of St. Edward's Roman Catholic Church. Music will be provided by the Towson State University Gospel Choir. Admission free. For information, call 685-0330.