Say Hello To –   JACK BAKER—whose nickname around NBC’s Chicago studios is “The Louisiana Lark,” partly because he was born in Shreveport, partly because he loves to sing. His real name is Ernest Mahlon Jones, he has been a semi-pro baseball player, a baseball coach and a schoolteacher, and his job as star soloist on this morning’s Breakfast Club is the result of an audition he took at NBC back in 1936.   
       Betty Barclay   __ was selling Sammy Kaye ’s records in a music shop in Macon, Go., when she decided that some day she would be the vocalist with his band. Today she is appearing with him on both Sunday Serenade  and So You Want to Lead a Band, over the ABC network. She admits that it took several preliminary jobs with other name bands and her singing of “I’m a Big Girl Now” to put her where she wanted to be.