LESSON THIRTY-FIVE. "HOOK-UPS."

Or Methods of Connecting the Instruments.

"Hook-ups" or circuit diagrams showing the manner of connecting various instruments are well worth considerable study if one is desirous of securing the greatest selectivity and distance from his apparatus.

There are almost an endless number of ways and combinations of ways of connecting apparatus, and strange to say, different people seem to be able to secure the best results with widely different methods. In spite of the fact that circuits of this kind are very numerous they can all be reduced to a few fundamental forms and an understanding of these forms will enable a person to devise his own "hook-ups" at will.

Transmitting circuits are fundamentally almost the same. The only real difference in arrangement is made by interchanging the condenser and spark gap. Either one may be placed across the terminals of the induction coil or transformer. There is no difference in the results.

FIG. 65.

Consider the circuit shown in the accompanying illustration. The action of the transformer is to charge the condenser to such a point that the voltage is sufficient to leap the spark gap and cause a discharge. The rush of current which is oscillatory takes place through the condenser, spark gap and primary turns of the helix, or in other words through the closed circuits. The secondary turns of the helix, which are those forming part of the aerial circuit, are larger in number than those of the primary, and because of this ratio cause currents of higher voltage than those of the condenser to be impressed upon the aerial system. The currents in the aerial system surge up and down the aerial through the helix into the ground.

FIG. 66. Receiving Circuits.

A shows a simple receiving circuit wherein a single slide tuning coil is connected to a detector. The high frequency currents generated in the aerial surge up and down the system and pass through the detector on their way to the ground. By moving the slider back and forth the electrical length of the circuit may be varied to suit the length of the incoming waves. Oscillations may be forced upon such a circuit, that is, if the waves are very powerful they will pass through the system and effect the detector no matter whether the slider is adjusted to suit them or not. This would cause interference and confusion in case more than one station were operating at a time.

By adding a second slider and a condenser as shown in B, this may be avoided to a considerable extent, for slider No. 1 may be adjusted to the desired signals and slider No. 2 placed in a position such as will give the branch of the circuit from the aerial, through the coil and into the ground of which it is a part, a period suited to the objectionable wave and so carry off the latter into the ground without effecting the detector. The desired signals will pass into the ground through the other branch of the circuit and operate the detector which lies in their path. The selectivity of the outfit may be further increased by the addition of a variable condenser.

A variable condenser may be placed in one or more of a great many positions. The accompanying illustrations show several. The effect of a condenser placed in series with the ground or aerial is just the opposite of that of a loading coil. It decreases the period and shortens the wave length to which it is adapted.

The Amateur’s Wireless Handy Book shows over one hundred wiring diagrams starting from the simplest and going to the most complicated in a natural sequence.

Any of the Following

Practical Books

will be sent At Once, Post-paid on receipt of price.

There is very little danger of losing currency in a letter if the following directions are observed:

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COLE & MORGAN

Publishers of the Arts and Sciences Series

P. O. Box 1473 New York, N. Y.

The Boy Electrician

Practical Plans for Electrical Toys and Apparatus, with an Explanation

of the Principles of Everyday Electricity.

By ALFRED P. MORGAN.

Author of "Wireless Telegraph Construction for Amateurs" and "Wireless

Telegraphy and Telephony," etc.

With full-page Illustrations and 324 Working Drawings and Diagrams

by the author. 8vo., Cloth, Net Price, $2.00.

This is the age of electricity. The most fascinating of all books for a boy must therefore be one dealing with the mystery of this ancient force and modern wonder, even a mere list of whose services is impossible. The best qualified of experts to instruct boys, Alfred P. Morgan, has in a book far superior to any other of its kind told not only how to make all kinds of motors, telegraphs, telephones, batteries, etc., and to do so economically, but has explained the principles upon which these depend for operation, and how the same thing is done in the every-day world be well presented and so attractive is this really great book that it will be an education for any bright boy to have it, as well as the best kind of a moral safeguard, by leaving no time or thought for evil, and a means of future benefit beyond the power of any one to reckon. Glancing over the pages of this book, one cannot but be impressed by the excellent illustrations, clearness of expression and the large number of subjects that are covered. It is beyond doubt the best book in this line that has ever been written or published. It is a book that will delight every boy who has a leaning towards electrical experiments. The author writes in a clear and chatty style and while he has a thorough technical knowledge of his subject he has succeeded in treating it in a simple manner so that it is readily intelligible to his young readers.

Among the Chapter Headings and Contents are:

Magnets and Magnetism—Static Electricity—Static Electric Machines—Cells and Batteries—Electro-Magnetism and Magnetic Induction—Electrical Units—Electrical Appurtenances—Electrical Measuring Instruments—Bells, Alarms and Annunciators—Electric Telegraphs—Microphones and Telephones—Induction Coils—Transformers—Wireless Telegraphy—Wireless Telephony—Electric Motors—Dynamos—An Electric Railway—Miniature Lighting—Miscellaneous Electrical Apparatus.

READ WHAT HAS BEEN SAID OF IT.

"Even a casual glance through the many pages of the book does not fail to emphasize the fact that Mr. Alfred P. Morgan has indeed succeeded well in giving the juvenile electricians a work that has long been sought."—Popular Electricity.

"We have no hesitation in commending the book to the attention of the juvenile audience for which it is intended."—Boston Post.

"A great book for enterprising boys. Bright boys will highly appreciate it and feel like thanking the wideawake publishers for putting such a reliable and interesting work in the field."—New Haven Journal.

"The book covers the subject of electricity thoroughly in all its phases and is a splendid acquisition to any boy’s library."—Detroit Times.

"In this age of electricity a book like the present one is both fascinating and valuable especially to boys. The book is attractive with its many illustrations and will prove of much educational value for any bright boy."—Zion’s Herald.

"This is an admirably complete and explicit handbook for young boys who fall under the spell of tinkering with electrical apparatus."—Boston Transcript.

"Well presented and attractive this book will be a source of great benefit and delight for any bright boy."—New Orleans Times-Picayune.

Price, $2.00, Postpaid

COUNTLESS OTHER MAGAZINES, NEWSPAPERS AND LIBRARIES HAVE

ENDORSED THIS GREAT BOOK. SEND FOR A COPY NOW.

If you are interested in this great book, write for our 8-page special

descriptive circular.

Wireless Telegraphy and Telephony Simply Explained

By ALFRED P. MORGAN.

A NEW BOOK by the author of "Wireless Telegraph Construction for Amateurs."

This is undoubtedly one of the most complete and comprehensive treatises on the subject ever published, and a close study of its pages will enable one to master all the details of the wireless transmission of messages. The author has filled a long-felt want and has succeeded in furnishing a lucid, comprehensible explanation in simple language of the theory and practice of wireless telegraphy and telephony. The book treats the subject from an entirely new standpoint. Several very novel and original ideas have been carried out in its making. It is well illustrated by over one hundred and fifty interesting photographs and drawings. All diagrams have been made in perspective showing the instruments as they actually appear in practice. The drawings are carefully keyed and labeled. Many of the photographs are accompanied by phantom drawings which reveal the name and purpose of each part.

It is a book which the wireless experimenter cannot afford to be without. It will prove even more valuable to the layman.

Among the contents are: Introductory. Wireless Transmission and Reception. The Ether. Electrical Oscillations. Electromagnetic Waves. The Means for Radiating and Intercepting Electric Waves. Aerial Systems. Earth Connection. The Transmitting Apparatus. Current Supply. Spark Coils and Transformers. Condensers. Helixes. Spark Gaps. Anchor Gaps. Aerial Switches, Etc. The Receiving Apparatus. Detectors, Etc. Tuning Coils and Loose Couplers. Variable Condensers. Tuning and Coupling. Directive Wave Telegraphy. The Dignity of Wireless. Its Applications and Service. Wireless in the Army and Navy. Wireless on an Aeroplane. How a Message is Sent and Received. The Wireless Telephone. The Ear. How We Hear. Sound and Sound Waves. The Vocal Cords. The Structure of Speech. The Telephone Transmitter and Receiver. The Photophone. The Thermophone. The Selenium Cell.

Handsomely Bound in Cloth with Embossed Cover. (Postpaid, $1.00)

Build Your Own Wireless Instruments

Complete Up-to-the-Minute Authentic Practical

WIRELESS TELEGRAPH CONSTRUCTION FOR AMATEURS

By ALFRED POWELL MORGAN

3d EDITION

220 Pages 163 Illustrations

Price, $1.50, Postpaid

Handsomely Bound in Silk Cloth

Thoroughly up to date and unusually complete. Gives in minute detail, full directions for constructing wireless apparatus and various outfits capable of receiving from 100 to 1,500 miles and transmitting 3 to 100 miles. Also clearly explains the purpose and action of each instrument. Directions for Operating and Adjusting, etc.

A SPLENDID TREATISE OF WIRELESS ALONG

CONSTRUCTIVE LINES

Price, $1.50, Postpaid

The value of this book has been greatly increased by the addition of much new subject matter and many illustrations of recent interest.

The new text explains fully how to build the most recent forms of Quenched Gaps. Rotary Gaps, Dough-Nut Tuners, Kick-back Preventers, Audion Detectors and numerous other instruments, accompanied by dimensioned working drawings. Several very interesting and instructive photographs have been included.

I.—Introduction. II.—The Apparatus. III.—Aerials and Earth Connections. IV.—Induction Coils. V.—Interrupters. VI.—Transformers. VII.—Oscillation Condensers and Leyden Jars. VIII.—Spark Gaps or Oscillators. IX.—Transmitting Helixes. X.—Keys. XI.—Aerial Switches and Anchor Gaps. XII.—Hot Wire Ammeter. XIII.—Oscillation Detectors. XIV.—Tuning Coils and Tuning Transformers. XV.—Receiving Condensers. XVI.—Telephone Receivers and Headbands. XVII.—Operation. XVIII.—The Amateur and the Wireless Law. How to Secure a License. Oscillation Helix. Quenched Spark Gap. Rotary Gaps. Kick-Back. The Variometer. New Crystal Detectors. The Audion.—Appendix.

ENDORSED BY WIRELESS CLUBS THROUGHOUT THE COUNTRY AS BEING

THE MOST PRACTICAL BOOK PUBLISHED ON WIRELESS.

IF YOU ARE INTERESTED IN WIRELESS YOU NEED THIS BOOK

Model Flying Machines

HOW TO BUILD AND FLY THEM

Will prove interesting and valuable.

Have you ever built and flown a Model Racer?

If not, you have missed something.

Price, 25 Cents, Postpaid.

Model Aeroplaning is one of the most fascinating and instructive of sports.

Thousands of young men and boys have formed Model Aero Clubs and organized Flying Contests throughout the country.

"MODEL FLYING MACHINES" of the Arts and Sciences series is the only book giving reliable data and instructions for the construction of practical Model Aeroplanes.

IF YOU ARE A BEGINNER, this is the book that you ought to have. It will start you right. It tells how to build seven different types of machines, starting with the simplest Monoplane and finishing with several Long Distance Racing Models.

IF YOU ARE INTERESTED IN MODEL AEROPLANING, this book will prove the one you have been looking for. Gives valuable "Kinks". Tells how to carve propellers, make winders, adjust and fly machines, etc. Fully illustrated with large size, detailed working drawings, showing the exact size of each part. Twelve full-page plates.

Printed on first-class paper. Heavy cover in three colors.

Sent postpaid by return mail upon receipt of 25 cents.

EVERY MODEL AVIATOR OUGHT TO HAVE A COPY

Experimental Wireless Construction

EIGHTY-SIX PAGES NINETY-THREE ILLUSTRATIONS

Only 25 Cents, Postpaid

Here at last is the book which every young experimenter interested in constructing his own wireless apparatus has been looking for.

A book which tells how to build apparatus which anyone would be proud to own. It is a more advanced book than "Wireless Construction and Installation for Beginners," and describes apparatus which is much more elaborate and sensitive. The instruments have all been the subject of considerable experimental work and study. All the apparatus has been put to practical test and carefully improved by clever experts. By purchasing this book you get the benefit of vast knowledge and experience and are enabled to build far better instruments than by following your own designs and haphazard methods.

THE TREMENDOUS POPULARITY OF THIS VALUABLE LITTLE BOOK IS ONLY AN INDICATION OF ITS GREAT WORTH.

It has only been on the market a short time, yet the sales will undoubtedly soon reach a point which would indicate that experimenters unquestionably consider, that in proportion to its size, it is the best book on the market.

It does not describe any old or obsolete forms of wireless apparatus but only the latest types of aerials, spark coils, keys, gaps, condensers, helixes, oscillation transformers, loose couplers, tuning coils, detectors, loading coils, variable condensers, aerial switches, etc.

IT IS ONE OF THE MOST DETAILED AND THOROUGH BOOKS EVER PUBLISHED.

The information is all intensely practical. Complete directions and dimensions are given. Nothing is left to be guessed at. The book must really be seen to be appreciated.

Partial Contents

Chapter I.—THE AERIAL. The Location of the Station. The Construction of an Operating Bench. The Aerial and Ground. The Supports or Masts. Types of Aerials. How to Erect an Aerial. Protection from Lightning, Etc.

Chapter II.—SPARK COILS. The Construction of Spark Coils. A 1/4-inch Spark Coil. A 1/2-inch Spark Coil. A 1-inch Spark Coil. A 1 1/2-inch Coil. A 2-inch Coil. Sources of Current. Dry Cells. Storage Cells. Wireless Keys, Etc.

Chapter III.—TRANSMITTING APPARATUS AND ITS CONSTRUCTION. Step-down Transformers. Spark Gaps. The Oscillation Condenser. Leyden Jars. Helixes. Oscillation Transformers, Etc.

Chapter IV.—THE RECEIVING APPARATUS AND ITS CONSTRUCTION. A Silicon Detector. A Galena Detector. The Double Slide Tuning Coil. How to Make a Fixed Condenser. Building a Loose Coupler. The Loading Coil. How to Make a Variable Condenser, Etc.

Chapter V.—ARRANGEMENT AND OPERATION OF THE APPARATUS. Aerial Switches. The Buzzer Test. Using More Than One Detector. Shunting the Detector. Complete Outfits. Portable Sets. The Operation of the Station, Etc.

The New Amateur’s Wireless

Handy Book

FOURTH EDITION

Completely Revised and Enlarged

You Cannot Afford To Be

Without This Book

Price 25 Cents, Postpaid

If you want to be an expert and an authority you must surround yourself with all available aids and helps. You have one of the best in the AMATEUR’S WIRELESS HANDY BOOK.

THERE HAVE BEEN MORE COPIES OF THIS GREAT BOOK SOLD THAN OF ANY OTHER WIRELESS BOOK.

It contains nearly SIX THOUSAND calls of Wireless Stations, including all Land Stations, Ship Stations, U. S. Army and Navy Stations and all AMATEURS licensed to date of publication.

Every registered station of the U. S. is included. They are all there. All the calls are classified alphabetically. The list is the most reliable and complete in existence. All obsolete stations have been abolished. All corrections and changes have been made from the official lists.

BUT, THAT IS NOT ALL.

THE CODES, BOTH MORSE AND CONTINENTAL, are shown in the form of two large full-page charts printed in heavy black type so that they can be read from a distance.

A BEGINNER’S SPEED CHART of both Codes so arranged that the codes may be quickly learned or consulted is provided.

ALL THIS ABBREVIATIONS used so constantly by the wireless operator to save time and labor are included. There are a couple of pages of them.

AND LAST BUT NOT LEAST

Nearly 100 large hook-ups of wiring diagrams fully illustrated in a concise and clear manner. Loop and straightaway aerials, grounds, helixes, spark gaps, anchor gaps, leyden jars, induction coils, transformers, keys, aerial switches, tuning coils, loading coils, loose couplers, variometers, fixed condensers, silicon, electrolytic, carborundum, perikon and audion detectors, telephones, potentiometers, etc., you can find them all and how to connect. A hook-up for any set accompanied by full explanation. None are missing. They are all there. There are no two alike.

The most complete and reliable data ever collected. The result of thousands of experiments by some of the most famous wireless experts in the country.

Read now before the supply is exhausted or you forget. You will be sorry if you don’t.

SENT ANYWHERE POSTPAID FOR 25 CENTS

Note: This book is always kept up-to-date by frequently issuing new editions. Send for the latest copy.

Wireless Construction and Installation for Beginners

SEVENTY-THREE PAGES SIXTY-SEVEN ILLUSTRATIONS.

(Second Edition.)

A Practical Handbook giving detailed instructions for the Construction and Operation of a Boy’s Wireless Outfit.

Only 25c. Prepaid

An indispensible book for the young wireless experimenter. It not alone shows how to build the various instruments but describes their actual workings and tells how to operate them.

EVERY BOY IS ADVISED TO

SEND FOR A COPY

Written in a very clear and simple style, the book is invaluable to a beginner. He will be able with its aid to construct simple apparatus of the latest and approved type. The instruments described in the book have been the subject of considerable experimental work and special study. They are modeled along simple lines so that they will be easy and inexpensive to construct, but at the same time combine features which make them very sensitive and capable of receiving or transmitting messages greater distances than some more complicated apparatus.

THIS BOOK, CONSIDERING ITS WORTH, IS A GIFT AT 25c.

There are no old or obsolete forms of wireless apparatus discussed, but only the latest types of tuning coils, receiving transformers, fixed condensers, keys, spark coils, detectors, etc. The book is illustrated by numerous detailed working drawings giving all dimensions. Several full-page views of the apparatus enable the beginner to fully comprehend the text.

THE MOST THOROUGH AND COMPLETE ELEMENTARY WIRELESS

CONSTRUCTION BOOK PUBLISHED

The pages on the construction and installation of aerials will be found to be of considerable help to the experimenter, for it is here that the most trouble is experienced by the beginner. The practical and helpful information on this subject is alone worth several times the cost of the book.

PARTIAL CONTENTS

Chapter I.—WIRELESS TELEGRAPHY. An intensely interesting subject; amateur wireless telegraphy; the purpose of the aerial and ground; the apparatus used to send messages; the apparatus used to receive messages.

Chapter II.—AERIALS AND GROUNDS. Where to put up the aerial; types of aerials; the "T" aerial; the masts; the wire; insulators; leading in the wires; the ground.

Chapter III.—HOW TO BUILD AND OPERATE THE SIMPLEX DOUBLE SLIDE RECEIVING OUTFIT. The tuning coil; the tube; the sliders; the fixed condenser; the detector parts; assembling the set; connecting the instruments; operation.

Chapter IV.—HOW TO BUILD THE SIMPLEX LOOSE COUPLER, DETECTOR AND CONDENSER. The base; the primary; the secondary; the pillar; the switch; How to make the Simplex cat whisker detector; How to make the Simplex fixed condenser; How to connect the apparatus; How to tune with the loose coupler; How to adjust the detector.

Chapter V.—TELEPHONE RECEIVERS AND HEADBANDS.

Chapter VI.—HOW TO BUILD THE SIMPLEX SPARK COIL. The core; the secondary; the condenser; the coil heads; the base; the interrupter parts; the bridge.

Chapter VII.—HOW TO MAKE THE SIMPLEX KEY.

Chapter VIII.—HOW TO CONNECT AND OPERATE THE APPARATUS. How to connect and operate a complete wireless station; How to operate; the code, etc.

The Operation of Wireless Telegraph Apparatus

Do your Wireless friends come to you for advice on constructing and operating their apparatus or do you go to them for information?

Here is a chance for YOU to become the authority.

This book is a necessity to every Progressive Experimenter.

It shows how to obtain the very highest efficiency from any station, and how to comply with the law. How to tune, adjust your detector, spark gap, phones, etc.

Price, 25 Cents, Postpaid.

This book was written for the wireless experimenter who has passed the amateur stage, but explains how the beginner also can obtain the very best results from his station. It contains much useful information to this end and many "kinks".

IT SHOWS HOW to receive or send on long or short wave lengths with highest efficiency, to tune for longest distance reception of messages, to use the buzzer test, how to test and connect condensers, receivers, etc., how to use receiving transformers, variometers, etc., all with highest efficiency in view.

IT ALSO DESCRIBES the construction and use of a simple, inexpensive wave meter to tune the station to any desired wave length, and tells how to obtain a sharp wave and a pure wave.

EXTRACTS FROM THE LAW are also given in such a manner that they are easily understood.

If you want to get the best results from your station this is your opportunity.

Three New Books on Home Made

Electrical Apparatus

or rather, three parts of one book, each 25 cents per copy, are now in preparation and should be ready in June, 1917.

They will cover every kind of electrical apparatus, including primary and storage batteries, dynamos and motors, induction coils, rectifiers, transformers, telegraphs and telephones, etc.—all of which have actually been built.

The three parts will also be furnished as a single volume in cloth covers at $1.00 per copy, postpaid.

If interested, simply send us a postal and when the books are ready we will send you full descriptions.

COLE & MORGAN

Publishers of the Arts and Sciences Series

P. O. Box 1473 NEW YORK, N. Y.

*** END OF THIS PROJECT GUTENBERG EBOOK LESSONS IN WIRELESS TELEGRAPHY ***