Popular Electronics Electronic Experimenter's Handbook 1983. Tools & Equipment For Electronic Workbenches, A Low-Cost 16-LED Logic Monitor, Build A Motion-Detector Alarm, A Low-Cost A/D Converter, Build A Metal Locator, How To Add Triggered Sweep To An Oscilloscope,  A 3-Way Drive System For Speakers, Special Counter Circuits For Experimenters, Measuring Large Currents With A DMM.