Metro’s ECC needed to upgrade its radio systems to meet the APCO Project 25 (P25) digital radio standards. P25’s goal is to enhance public safety responders’ capabilities to communicate with each other and achieve timely responses. Puckett Engineering was retained to ensure the critical infrastructure could support the new systems. This included coordination with Motorola engineers about the new equipment’s power and redundancy requirements, modification of existing equipment and addition of new circuits, the addition of redundant power supplies and redundant equipment from UPS systems, and incorporation of wiring methods for compatibility with power system harmonics. PDF Case Study.