Telegraph Transmitting Set-A 500- to 1000-mile C. W. Telegraph Transmitting Set--The Apparatus Required--The Alternating Current Power Transformer-Connecting Up the Apparatus.

XVIII. WIRELESS TELEPHONE TRANSMITTING SETS WITH DIRECT AND ALTERNATING CURRENTS

A Short Distance Wireless Telephone Transmitting Set--With 110-volt Direct Lighting Current--The Apparatus You Need--The Microphone Transmitter--Connecting Up the Apparatus--A 25- to 50-mile Wireless Telephone Transmitter--With Direct Current Motor Generator--The Apparatus You Need--The Telephone Induction Coil--The Microphone Transformer--The Magnetic Modulator--How the Apparatus is Connected Up--A 50- to 100-mile Wireless Telephone Transmitter--With Direct Current Motor Generator--The Oscillation Choke Coil--The Plate and Grid Circuit Reactance Coils--Connecting up the Apparatus--A 100- to 200-mile Wireless Telephone Transmitter--With Direct Current Motor Generator--A 50- to 100-mile Wireless Telephone Transmitting Set--With 100-volt Alternating Current--The Apparatus You Need--The Vacuum Tube Rectifier--The Filter Condensers--The Filter Reactance Coil-- Connecting Up the Apparatus--A 100- to 200-mile Wireless Telephone Transmitting Set--With 110-volt Alternating Current--Apparatus Required.

XIX. THE OPERATION OF VACUUM TUBE TRANSMITTERS

The Operation of the Vacuum Tube Oscillator--The Operation of C. W. Telegraph Transmitters with Direct Current--Short Distance C. W. Transmitter--The Operation of the Key Circuit--The Operation of C. W. Telegraph Transmitting with Direct Current--The Operation of C. W. Telegraph Transmitters with Alternating Current--With a Single Oscillator Tube--Heating the Filament with Alternating Current--The Operation of C. W. Telegraph Transmitters with Alternating Current-- With Two Oscillator Tubes--The Operation of Wireless Telephone Transmitters with Direct Current--Short Distance Transmitter--The Microphone Transmitter--The Operation of Wireless Telephone Transmitters with Direct Current--Long Distance Transmitters--The Operation of Microphone Modulators--The Induction Coil--The Microphone Transformer--The Magnetic Modulator--Operation of the Vacuum Tube as a Modulator--The Operation of Wireless Telephone Transmitters with Alternating Current--The Operation of Rectifier Vacuum Tubes--The Operation of Reactors and Condensers.

XX. HOW TO MAKE A RECEIVING SET FOR $5.00 OR LESS.

The Crystal Detector--The Tuning Coil--The Headphone--How to Mount the Parts--The Condenser--How to Connect Up the Receptor.

APPENDIX

Useful Information--Glossary--Wireless Don'ts.

LIST OF FIGURES

Fig. 1.--Simple Receiving Set

Fig. 2.--Simple Transmitting Set

(A) Fig. 3.--Flat Top, or Horizontal Aerial

(B) Fig. 3.--Inclined Aerial

(A) Fig. 4.--Inverted L Aerial

(B) Fig. 4--T Aerial

Fig. 5.--Material for a Simple Aerial Wire System

(A) Fig. 6.--Single Wire Aerial for Receiving

(B) Fig. 6.--Receiving Aerial with Spark Gap Lightning Arrester

(C) Fig. 6.--Aerial with Lightning Switch

Fig. 7.--Two-wire Aerial

(A) Fig. 8.--Part of a Good Aerial

(B) Fig. 8.--The Spreaders

(A) Fig. 9.--The Middle Spreader

(B) Fig. 9.--One End of Aerial Complete

(C) Fig. 9.--The Leading in Spreader

(A) Fig. 10.--Cross Section of Crystal Detector

(B) Fig. 10.--The Crystal Detector Complete

(A) Fig. 11.--Schematic Diagram of a Double Slide Tuning Coil

(B) Fig. 11.--Double Slide Tuning Coil Complete

(A) Fig. 12.--Schematic Diagram of a Loose Coupler

(B) Fig. 12.--Loose Coupler Complete

(A) Fig. 13.--How a Fixed Receiving Condenser is Built up

(B) Fig. 13.--The Fixed Condenser Complete

(C) and (D) Fig. 13.--Variable Rotary Condenser

Fig. 14.--Pair of Wireless Headphones

(A) Fig. 15.--Top View of Apparatus Layout for Receiving Set No. 1

(B) Fig. 15.--Wiring Diagram for Receiving Set No. 1

(A) Fig. 16.--Top View of Apparatus Layout for Receiving Set No. 2

(B) Fig. 16.--Wiring Diagram for Receiving Set No. 2

Fig. 17.--Adjusting the Receiving Set

(A) and (B) Fig. 18.--Types of Spark Coils for Set No. 1

(C) Fig. 18.--Wiring Diagram of Spark Coil

Fig. 19.--Other Parts for Transmitting Set No. 1

(A) Fig. 20.--Top View of Apparatus Layout for Sending Set No. 1

(B) Fig. 20.--Wiring of Diagram for Sending Set No. 1

Fig. 21.--Parts for Transmitting Set No. 2

(A) Fig. 22.--Top View of Apparatus Layout for Sending Set No. 2

(B) Fig. 22.--Wiring Diagram for Sending Set No. 2

Fig. 23.--Using a 110-volt Direct Current with an Alternating current Transformer

Fig. 24.--Principle of the Hot Wire Ammeter

Fig. 25.--Kinds of Aerial Switches

Fig. 26.--Wiring Diagram for a Complete Sending and Receiving Set No. 1

Fig. 27.--Wiring Diagram for Complete Sending and Receiving Set No. 2

Fig. 28.--Water Analogue for Electric Pressure

Fig. 29.--Water Analogues for Direct and Alternating Currents

Fig. 30.--How the Ammeter and Voltmeter are Used

Fig. 31.--Water Valve Analogue of Electric Resistance

(A) and (B) Fig. 32.--How an Electric Current is Changed into Magnetic Lines of Force and These into an Electric Current

(C) and (D) Fig. 32.--How an Electric Current Sets up a Magnetic Field

Fig. 33.--The Effect of Resistance on the Discharge of an Electric Current

Fig. 34.--Damped and Sustained Mechanical Vibrations

Fig. 35.--Damped and Sustained Electric Oscillations

Fig. 36.--Sound Wave and Electric Wave Tuned Senders and Receptors

Fig. 37.--Two Electrode Vacuum Tube Detectors

Fig. 38.--Three Electrode Vacuum Tube Detector and Battery Connections

Fig. 39.--A and B Batteries for Vacuum Tube Detectors

Fig. 40.--Rheostat for the A or Storage-battery Current

(A) Fig. 41.--Top View of Apparatus Layout for Vacuum Tube Detector Receiving Set

(B) Fig. 41.--Wiring Diagram of a Simple Vacuum Tube Receiving Set

Fig. 42.--Grid Leaks and How to Connect them Up

Fig. 43.--Crystal Detector Receiving Set with Vacuum Tube Amplifier (Resistance Coupled)

(A) Fig. 44.--Vacuum Tube Detector Receiving Set with One Step Amplifier (Resistance Coupled)

(B) Fig. 44.--Wiring Diagram for Using One A or Storage Battery with an Amplifier and a Detector Tube

(A) Fig. 45.--Wiring Diagram for Radio Frequency Transformer Amplifying Receiving Set

(B) Fig. 45.--Radio Frequency Transformer

(A) Fig. 46.--Audio Frequency Transformer