179.—Step-Down Transformer. .................................. Fig. 180.—Core Dimensions. ........................................ Fig. 181.—The Core, Assembled and Taped. .......................... Fig. 182.—Transformer Leg. ........................................ Fig. 183.—Fiber Head. ............................................. Fig. 184.—Leg with Heads in Position for Winding. ................. Fig. 185.—How to make a Tap in the Primary by soldering a Copper Strip to the Wire. ................................................ Fig. 186.—The Transformer completely Wound and ready for Assembling. Fig. 187.—Wooden Strips for mounting the Transformer on the Base. . Fig. 188.—Details of the Switch Parts. ............................ Fig. 189.—The Complete Switch. .................................... Fig. 190.—Diagram of Connections. ................................. Fig. 191.—Top View of the Transformer. ............................ Fig. 192.—Side View of the Transformer. ........................... Fig. 193.—Little Waves spread out from the Spot. .................. Fig. 194.—A Simple Transmitter. ................................... Fig. 195.—A Simple Receptor. ...................................... Fig. 196.—Molded Aerial Insulator ................................. Fig. 197.—A Porcelain Cleat will make a Good Insulator for Small Aerials. .......................................................... Fig. 198.—Method of Arranging the Wires and Insulating them from the Cross Arm or Spreader. ............................................ Fig. 199.—Various Types of Aerials. ............................... Fig. 200.—A Ground Clamp for Pipes. ............................... Fig. 201.—Details of the Tuning Coil. ............................. Fig. 202.—Side and End Views of the Tuning Coil. .................. Fig. 203.—Complete Double-Slider Tuning Coil. ..................... Fig. 204.—A Simple Loose Coupler. ................................. Fig. 205.—Details of the Wooden Parts. ............................ Fig. 206.—Side View of the Loose Coupler. ......................... Fig. 207.—Top View of the Loose Coupler. .......................... Fig. 208.—End Views of the Loose Coupler. ......................... Fig. 209.—Complete Loose Coupler. ................................. Fig. 210.—A Crystal Detector. ..................................... Fig. 211.—Details of the Crystal Detector. ........................ A Double Slider Tuning Coil. ...................................... A Junior Loose Coupler. ........................................... Crystal Detectors. ................................................ Fig. 212 Details of the "Cat Whisker" Detector. ................... Fig. 213.—Another Form of the "Cat-Whisker" Detector. ............. Fig. 214.—"Cat-Whisker" Detector.