Equireplicate balanced binary codes for oligo arrays

In the manufacture of oligo arrays for DNA hybridization experiments, manufacturing defects must be detected and their position determined. The design of manufacturing protocols for such oligo arrays leads to a combinatorial problem, requiring certain binary codes which have an additional balance property. Constructions using block designs and packings for these codes, within a range of interest in a practical manufacturing application, are developed. The focus is on equireplicate codes, constant weight codes in which every bit position is a one equally often.