This is a Sources Sought notice for market research to identify potential contractors capable of updating the AN/APR-39D(V)2 radar warning receiver system. The work involves Non-Recurring Engineering to replace a circuit card assembly, port and update software, and deliver updated processors. The anticipated period of performance begins in August 2026, and the contract type is expected to be Cost Reimbursable. Required capabilities include expertise in advanced RWR technology, operational software improvements, and delivering a circuit card assembly solution that is form/fit/function compatible and interfaces with specified airborne platforms and existing ASE suite components. The performance location is associated with the Naval Air Systems Command (NAVAIR) at Patuxent River, MD.