Low-Cost, Computer-Free Spin Echo Generator Board

A Spin Echo Generator Board has been designed as an affordable tool for MR system quality assurance, demonstration, and education. Inspired by earlier work on inexpensive spin echo generator circuit boards, the board uses low-cost digital timing circuits for pulse generation and mixers for RF pulse gating, without requiring a computer. It produces a simple rectangular excitation pulse followed by a refocusing pulse, with user-adjustable pulse widths, TE, and TR delays. The board features an integrated T/R switch, pre-amplifier, and an onboard 9-V battery holder for standalone operation. External requirements include only a synthesizer, RF power amplifier, oscilloscope for display, and a tuned RF coil placed within a magnet. The hands-on platform and real-time feedback support practical applications, such as verifying signal generation and coil performance. In an educational setting, the board enables students to explore how variations in timing parameters influence MR signal behavior. It provides a transparent learning environment in which students can investigate fundamental MRI concepts, including flip angle, resonance, and T₂ relaxation, through direct experimentation. Functionality is demonstrated on a 0.5-T tabletop magnet and 0.1-T whole-body MRI scanner.