The goal of this Phase II project is to double the number of detector front-end electronics channels in a positron emission tomographic (PET) scanner while maintaining or reducing the present size and cost. Achieving this goal will enable the use of smaller detector elements which are needed to improve PET image resolution and enhance the clinical use of PET. Doubling the density of the front-end electronics channels is possible through the use of advanced semicustom analog integrated- circuit technology which will halve the size of the present electronics. In addition to permitting a greater number of detector channels, the proposed front-end electronics will be more cost-effective, more compact, more reliable, and better performing than the existing discrete design. The tasks to be performed include: development of an in-house design capability, selection of a fabrication vendor, the detailed design of the functions in to a minimal chip-set and an associated printed circuit board, and integration of the new board into the company's commercial positron emission tomographic scanner. The feasibility of this approach was established during Phase I.