[Radiologic Physics] Ep 12 – Rectification

This episode covers rectification — the process of converting alternating current (AC) to direct current (DC) in the x-ray circuit. Prof. Arya explains why unrectified AC would allow reverse electron flow from anode to cathode during the negative half-cycle, risking tube damage and wasted exposure. The episode examines both early vacuum valve tube rectifiers and modern solid-state diodes, tracing the p-n junction mechanism that permits current to flow in only one direction, and compares half-wave and full-wave rectification in terms of pulse output, rectifier count, and clinical efficiency.The second half explores single-phase, three-phase, and high-frequency power supplies — comparing 6-pulse and 12-pulse configurations, voltage ripple percentages, and their effect on x-ray output and image quality. The high-frequency generator's inverter circuit is detailed step by step, highlighting its advantages in size, efficiency, and near-constant potential voltage. The episode closes with practical methods for detecting rectification failure — the spinning top test, synchronous spinning top, and oscilloscope.This episode aligns with the Equipment Operation and Quality Assurance content category — Radiographic Equipment subcategory — of the ARRT Radiography Examination Content Specifications.Audio content is adapted from original instructional material developed by Professor Sanjay Arya, M.S., R.T.(R)(MR) for radiologic technology education. Part of the Radiologic Physics series — Quantum Imaging Lab.© 2026 Quantum Imaging Lab. All rights reserved.