Secondary Source Bring up Cost Metrics and Net Present Value Calculation
Secondary source bring-up generates positive Net Present Value when unit cost savings and risk offsets exceed fixed tooling and qualification expenses.
EVT
Meaning
A preliminary build phase verifies that the core electronic and mechanical subsystems of a new product design function according to specifications. This phase, known as engineering validation test, utilizes early prototype boards to verify basic circuitry and power distribution. Test units are typically built without final enclosures to allow direct probe access to circuit traces.
Debug Cycle
Engineers use oscilloscopes and spectrum analyzers to capture signal integrity on high-speed data buses. This diagnostic work during the engineering validation test uncovers circuit design mistakes and thermal anomalies before tooling begins. Re-work is common at this stage, with technicians manually soldering jumpers and swapping passive components.
Firmware developers write basic hardware abstraction layers to bring up primary radios and interfaces.
Design Feedback
Schematic corrections generated during these early runs flow directly into the subsequent layout revision. Mechanical dimensions are adjusted to improve fit within the tentative housing design. This early physical proof minimizes the risk of discovering fundamental block failures during later, more expensive tooling cycles.
The phase concludes when all major functional blocks operate without critical workarounds.
Resource Allocation
Raw boards and loose silicon are purchased in small quantities to avoid excessive write-offs during early changes. Contract manufacturers allocate dedicated engineering lines rather than high-speed assembly lines for these manual builds. This restricted deployment of factory resources keeps development nimble while protecting the broader production schedule.
Engineers receive the verified prototypes to begin deep characterization of the radio and antenna performance under diverse environmental conditions.