- Built-in 400mAh micro SD supports up to 32GB and only supports SPI - Low operating noise, with reduced noise when measuring overtones - Add a micro SD card to store test data. This is a DIY device that provides a comprehensive function set to measure the vector network in a credit card form factor. It includes a 2.8 inch touch screen, a 400 mAh power supply, supports Tx/Rx measurements, and can measure the full parameters S11 and S21. If you need S12 and S22, you must manually change the wiring of the transceiver port - 4.Add support - Size and form factor: credit card style device designed for portable vector network measurements - Performance and capability: measures S-parameters with Tx/Rx access and supports data storage for test results - Use scenarios - On-site RF component testing: quickly measure S11 and S21 of antennas, filters, or matching networks at the field - DIY and hobby projects: use as a compact vector network analyzer for learning, prototyping, and experimentation - Educational demonstrations: teach S-parameters and network analysis with a portable, user friendly instrument - Compatibility and operation - SPI based micro SD storage for test data - Requirements for S12 and S22: requires manual wiring changes at the transceiver port - Practical notes - The device emphasizes a compact credit card form factor with a built-in display and data logging - The stated specifications reflect the built-in memory, measurement capabilities, and user interface features as described