High Frequency Apparatus Page xii

xii CONTENTS Chapter X. QUENCHED GAP APPARATUS Peculiar Characteristics of Sparks Produced with the Quenched Gap. Increase in Thickness or Volume and Decrease in Length. Production of a Flame as Thick as a Broomstick. Design for a Practical Form of Gap. Simple Patterns Required. Machine Work. Assembly of the Gap. Quenched Gap Transformers. Peculiar Characteristics. Low Secondary Potential. Data for a Two-Kilowatt Quenched Gap Transformer. Specifications for All Commercial Voltages and Frequencies. Construction of the Transformer. Caution to be Observed. Danger of Shock from the Low Resistance Secondary Winding. Suitable Secondary Condenser. General Hints. Electro-Therapeutic and X-Ray Apparatus. Chapter XI. PHYSICIANS' PORTABLE APPARATUS Requirements of the Ideal Outfit. Good Workmanship Required. Dangers of a Short Circuit Within the Cabinet. Importance of Establishing Confidence of the Patient. Transformer Outfit not Practicable for Amateur Construction. Design for Kicking Coil Outfit Within Reach of Builder. Standard Electro-Therapeutic Apparatus. Various Types and what they Cost. Possibilities and Limtiations. Special Direct Current Outfits. Apparatus Suitable for Dentists. Large Portable Outfits. Technical Description and Capabilities. Chapter XII. PHYSICIANS' OFFICE EQUIPMENT Powerful and Efficient Equipment for the Physicians' Office. Design for a One-Kilowatt Outfit with Apparatus Mounted upon a Table. Advantages of this Form of Construction. Imposing Appearance. Accessibility of the Component Parts. Construction of the Magnetic Leakage Transformer. Rotary Spark Gap. Stationary Spark Gap. Oscillation Condenser. Transformer for Vacuum Tube Work. Oil-Immersed Oscillation Transformer for X-Ray Work. D'Arsonval Treatment Transformer. Assembly of the Apparatus. Connecting and Using. 100 111 118