ITC/USA 2008 Conference Proceedings / The Forty-Fourth Annual International Telemetering Conference and Technical Exhibition / October 27-30, 2008 / Town and Country Resort & Convention Center, San Diego, California / The U.S. Army Research Laboratory (ARL) is exploring technologies to provide low-cost precision fires, applicable across both direct and indirect fire weapon systems. One of these applications involves a forward observer (FO) designating the target with a laser spot and a seeker on-board the munition detecting the reflected energy to allow terminal guidance. This approach, referred to as semi-active laser (SAL) guidance, has been utilized on numerous air-delivered munitions to include bombs, missiles and projectiles. However, the cost of these systems, driven by high quality optics, high sensitivity detectors and specialized electronics, has hampered their migration into gun-fired munitions such as mortars, artillery and grenades. To explore, develop and demonstrate minimal cost solutions, ARL invested in an Army Technical Objective (ATO) called Smaller, Lighter, Cheaper Munition Components (SLCMC). Specifically, SAL seeker hardware, predicated upon commercial components (COTS) and mass production techniques, is being prototyped for use with gun launched projectiles and laser target designators. The seeker system is comprised of several printed circuit board boards, a microprocessor, a quad-photo detector and, a molded optical lens unit. This seeker is designed to rapidly update the projectile boresight angle, interface with other strap-down sensors, and feed data into an on-board guidance, navigation & control (G,N&C) system to allow for projectile maneuvers. The seeker design and basic characteristics are discussed and presented through-out the paper and presentation.