Features:  The PC control software can export Touchstone (snp) files, which can be used for various radio design and simulation software.  The improved frequency algorithm can use the odd harmonic extension of si5351 to support the measurement frequency up to 900MHz.  It is mainly for the study of customers who can DIY.  It has no metal shield. The main advantage is that users with strong hands-on ability can open the machine to view the circuit structure. However, when measuring frequencies above 300M, it is easy to be interfered by other signals. So this product is recommended for learning principles and use at lower frequencies.  The 50k-300MHz frequency-range of the si5351 direct output provides better than 70dB dynamic.  The extended 300M-600MHz band provides better than 50dB of dynamics, and the 600M-900M band is better than 40dB of dynamics.  Small and portable, easy to use, this project aims to provide an RF gadget but useful instrument for enthusiast.    Specifications:  Material: PCB  Color: white  Measurement frequency: 50KHz~300MHz (50KHz~900MHz, enable extended firmware)(the products will be updated with the latest firmware before shipping, the actual measurement frequency is 50KHz~900MHz)  RF output: -13dbm (maximum -9dbm)  Frequency accuracy: <0.5ppm  Measurement-range: 70dB (50KHz-300MHz), (50dB (300M-600MHz), 40dB (600M-900MHz) enable extended firmware)  Port SWR: <1.1  Display: 2.8 inch TFT (320*240)  USB interface: USB type-C  Communication mode: CDC (serial)  USB: 5V 120mA  Battery: 1 * lithium battery, 3.7V, 450mAh (included)  Number of calibration points: 101 (fixed)  Number of scanning points: 101 (fixed)  Display tracking: 4, Marking: 4, Setting save: 5  PCB size: 85.5 * 54 * 11mm / 3.4 * 2.1 * 0.4in (without connectors and switches)  Package size: 190 * 100 * 30mm / 7.5 * 3.9 * 1.2in  Package weight: 141g / 5.0ounce    Package list:  1 * Host  1 * USB Type-C Data Cable  1 * SMA Female to Female Connector