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About The Sunday Oregonian. (Portland, Ore.) 1881-current | View Entire Issue (June 18, 1922)
9 THE SUNDAY OREGONIAN, PORTLAND, JUNE 18, 1922 .i)( .1 ' ' -, AW' FEW radio fans actually under stand the principles of that vry important unit of a radio receiving set the detector. Its ac tion is rei.!ly simple and can be easily explained without the use of many technical terms. Radio waves produce currents of electricity that alternate very rap idly. In fact they vibrate at such high frequency that there is no mechanism yet devised that will register them directly. However, here is where the de tector steps in and changes the high frequency current into a cur rent of one direction which will register ita slower pulses in a tele phone receiver. The detector acts on the principle of . rectifier. That is, it permits one direction of the alternating current to pass through, but refuses to allow the reverse pulse to pass. A great tnany chemical substances have the property of rectifying al ternating currents. Galena, a sul phide of lead, is one. It is believed that as the current flows in one d' reotion it partially decomposes the crystal separating a minute amount RADIO MUSIC REPRODUCTION DEPENDS ON ADJUSTMENTS Loud Speaker Should Be Acoustically Efficient to Get Best Results and Remedies Are Simple When Understood. ABU you having any trouble in getting a good reproduc tion of the radio music with your "loud speaker." There are many types of the "loud speaking" phone devices on the market, and some of them are far from being acoustically efficient It ia quite 4.h fromiAnt thine- tn hn.vA a voice come out of the horn that sounds as if it were talking or singing in Chinese. This is known as distortion and usually is caused by the faulty de sign of the loud speaker. Unless the horn is constructed scientifi cally there is apt to be mor,e or less of an echo which makes the signals indistinct and .hard to understand. Quite often the bad reproduction is due to the type of the receivers used with the horn. If very loud results are to be had, it frequently hap pens that there is a tinny rattle present. The only cure for this is to get a good receiver in which the clearance between the dia phirams and the magnets is mot too great. ' Another way to help a loud speaker . is to turn the opening RADIO QUERIES Editor Radio "Waves and Ripples: i Please answer the following questions through The Oregonlan. 1. Which is the best for all around purposes, a two-side tuner or a small loose-coupler? 2. Which would be the best for re ceiving, a one-wire aerial 200 feet long, or a two-wire aerial 200 feet long? 3. What is the sole purpose of each, (a) vario-coupler? (b) variometer? Can either be used to any advantage with a crystal set? 4. What is the meaning of vernier in applying to a variable condenser? 6. How many meters is it possible to receive with a 600-turn tapped honey comb? 6. How far can 1 receive with the stated honeycomb, crystal detector, fixed condenser, 3000-ohm phones, two-wire aerial 200 feet long and 50 feet high? A RADIO BUG, Candy. Or. 1. 1 A correctly designed loose coupler will be the better tuner for all-around purposes. 2. The one wire will be the best for receiving. 2. Both vario-coupler and vari ometer are variable inductances in which a movable coil rotates in and out of a stationary one. Either one can be used with good advantage in a crystal set. 4. The vernier of a variable con denser is a device that allows the variation of the condenser capacity to a very fine degree. 5. With a variable condenser of ?001 met. capacity you will be able to tune in wave lengths as high as 8000 meters. i 6. Under favorable conditions you ought to receive radiophone from as far as 25 miles and telegraph sig nals from several hundred miles away. Editor Radio Waves and Ripples: Please answer the following: 1. What Is the wave length of a single-wire aerial antenna 175 feet long. in cluding the lead in, 100 feet high on one end and 35 feet on the other? 2. Would it be practical to double it? 3. What Is the average range of a crystal set composed of a coll one inch . in diameter with 95 turner a crystal de tector and a pair of Manhattan phones? 4. ' Would I have better results if I used a fixed phone condenser? o. Is a lightning switch practical in a place like this? G. M., Portland, Or. 1. Approximately 260 meters. 2. For receiving purposes it is unnecessary to double it. 3. Tour coll is very poorly de signed. The diameter is too small. Make a coll out of a cardboard tube at least 3 inches in diameter and you will get better results. With a good tuning coil and favorable con dttioi. -ou may be able to hear radiophone from it least 25 miles away with a crys-a. set. N 4. The addition of a phone con-' denser will add to the sensitiveness of the set. 5. All radio installations should have a lightning protective switch so that the eerlal can be grounded outside the house during a lightning storm. Editor Radio Waves and Ripples: 1. Will I be able to receive your breicasts with a 180-foot antenna and lead In, one 43-plate variable condenser, two variometers, V. T. detector and 2000 ohm phones, or will I need another tun ing coil of some kind and a one or two step amplifier in addition? 2. What is the reason that the best receiving sets in eastern Oregon, so I am told, can receive San Francisco and Seat tle easier than they can receive Port land? S. Will it make any difference In re ceiving if you are located behind a steep hill providing your antenna is 35 or 40 feet high? A RADIO FAN, Heppner, Or. 1. If conditions in your locality are favorable, a regenerative re ceiver using only a detector ought to bring In Portland stations. If not. it might be necessary to add of lead and sulphur. The return current would make them combine again and absorb more heat, but I this the molecults refuse to do. J They will either be decomposed and j absorb heat or be combined and give off heat, but "not both. Only one phase of the current is allowed to pass and the current "s sues from the crystal in direct pulses. All crystal detectors must have fine points for contacts, so that tihe current can be concentrated at one spot to make its heating more apparent. Zincite, or natural oxide of zinc, iron pyrites (fool's gold), bornite copper-iron sul phide) and other crystals are very good rectifiers. Selecting a crystal is always a gamble. No two act just alike. Some are poor and some are excellent. Some poor ones are made good by heating them, and sometimes stood ones deteriorate. The great advan tage of a crystal is that it is cheap. There are a number of other de tectors "on the market that work better than the crystal, but they are more expensive. These are mainly the audion or vacuum tube types. The essential parts of these tuVes are: a hot filament lighted by a storage battery and" giving oK a stream of electrons, a charged grid of wire and a receiving plate. The flow of electrons from the filament is in effect a current of electricity. When oscillating currents pass through the tube they find It easy to travel with the flow of electrons, but difficult to go against them. So wefind that the vacuum zube detector is also a rectifier. The current emerging from the tube is changed into a direct pulsating one of one direction. Telephone receiv ers respond to direct currents. Each pulse excites their magnets to pull on the armature, and the latter, as it pounds on the air. reta up air waves, or the sounds that you hear when listen4ng in the phones. against the wall or a window. Move the horn to and from the wall until the signals are the loudest and the best. Usually this distance is about 1 inch, but it may vary with the type of the horn used. : Sometimes very good results may be had by simply placing the horn so that- the sound is directed intq one corner of the room. Either one of these ideas will take the tlnnl ness out of the music and make the voice much clearer. . v The best way to arrange the loud speaker so' that a perfect reproduc tion can be had is to put an ordinary chopping bowl over the month in such a way that the sound hits di rectly in the' center of the bowl. The bowl should be fastened with brass supports to the ba&e of the horn. Give the bowl a couple of coats of shellac and it will look very g-ood. This will improve the tone of the radio music so much that you will find your labor well repaid. It is not a new idea, but there are many radio novices who never have heard of it, and it is hoped thai they will try the stunt for imuprovlng their reception. , , ' - ... AND ANSWERS one or two steps of amplification. The addition of another tuning coil is not necessary as it will nly add more wave length to the circuit. which is not desired for reception of 360-meter radiophone. 2. Reception of radiophone de pends a whole lot on certain outside atmospherio and other conditions. Distant stations located in a certain direction from ' the receiving set often come in better than others located in another direction but closer in, on account of the con ditions along that direction beine? better than along the other. 3. If the aerial is too close to the hill it might interfere to some extent with the reception of signals coming from the other side of the hill. However, you can never tell what a set will do until you install it and get it to operate. Editor Radio Waves and Ripples: 1. Tou state that some head sets wound to 1000 ohms are better than oth ers wound to 2000 ohms. Is the Murdoclc set a reliable one? 2.. In the double head set of 20OO ohms, does that mean 20OO ohms in each phone or 1000 ohms to each? 3. What is a good test to give the double head set when purchasing same? 4. Will the home set described in The Oregonlan of March 5 receive radio music 10 miles attached to a resonance wave coil 88 Inches long, 2 SI inches in diam eter wound with number 82 gauge Insu lated wire? It not, what kind of a re ceiver should be used with said coll 7 5. . What size buzzer should one use to resemble the wireless code? 6. A dot and space are equal. What is the duration of amdot? How many dots and spaces should occur per minute average speed? 7. Will a panel made of woodpulp and glue be good to attach a set to? OLD RAIL FAN, Fernwood, Or. 1. The Murdock is one ot the re ijable phones on the market today. 1000 ohms for each phone. 3. Place both tips of the phone cords on the tongue. If you hear a good click in the receivers you will know that the receivers are aensi tive. 4. Tour coil is hot very well de signed for receiving "short waves. Wind about 80 turns of No. 22 sin gle cotton covered magnet wire on a cardboard tube 4 -inches in dia meter, tamer snaes or taps to a multiple switch will do to vary the number of turns desired. With such coil and favorable conditions you will hear the music from 10 miles away. 5. The high rrequency buzzer emits a tone which is very like the wireless telegraph sparks. 6. In radio code work three dots are equal to one dash. The average speed used in commercial wireless telegraph communication is 20 words of five letters a word a minute. 7. The wood pulp panel will do with the crystal type set. ' Editor Radio Waves and Ripples: I now receive music fairly well from sta tions KOW and KYG with a crystal set Could I receive better if I had a longer wave length? Would a variable con denser help in receiving? A FAN, Hillsboro, Or. As the wave length of the trans mitting stations is always the same you will gain nothing by increasing your wave 'lengthy The addition of a variable condenser should increase the sensitiveness of the set if con nected in the circuit correctly. Con nect in the aerial circuit in parallel with the tuning coll. Editor Radio Waves and Ripples: Could a loud-speaker be used on a crys tal set? J. P., Portland, Or. The loud speaker can only be used with good results in conjunction with an amplifier set. DR. CHARLES P. STEINMETZ PRESENTS v NEW THEORY REGARDING RADIO WAVES Chief Consulting Engineer of General Electric Company Delivers Lectures by Radio Wave of Average Broadcasting Station Said to Have Length of 360 Meters. r t'Bc r 1ktS& " v ei mm Dr. Charles P. Stelnmetz, chief consulting engineer of the General Electric theory regarding radio waves, delivering a lecture BT DR. CHARLES P. STEINMETZ. THE RADIO waves and the light are the same thing. The only difference is in wave length. The wave of the average broadcast ing station has a length of 360 meters, while the wave length in a beam of light is only one twenty thousandth of a centimeter and the wave length of the X-ray still hun dreds of times shorter." On the other hand, the electro-magnetic, waves of our long-distance transmission lines have five million meter wave length. The only difference between Tadio waves and light waves are those due to the difference of wave length. A radio wave passes through a brick wall, because the thickness of the wall -Is only a small fraction of the wave length, while a light wave is stopped by a thin sheet of metal, because the thickness of even the thinnest sheet of metal is many times the wave length of a light wave. For a long time we have believed that light is a wave motion of some hypothetical thing, called the ether. This, theory never was satisfactory, because it required that the ether must be so extremely thin that the earth and all bodies move through it with terrific speeds 100,000 feet per second without any trace of friction. And at the same time the ether must be a solid body of high rigidity. This is unreasonable. Fin ally the belief in an ether had to be abandoned as being contradicted Municipal Wireless Fills Great Need. Interlocking Broadcasting Sta tions Seen as Next Hove. ' WRELESS as a public necessity and a civic need with a system of interlocking municipal broadcast ing stations is the next general move in the radio field seen Dy experts who have been in touch with the various phases of radio development. The degree to which tnis has De come almost a popular demand is rapidly being emphasized in many of the eastern cities. The .public's interest In wireless telephony, with the purchase of thousands of radio sets for enter tainment purposes, has jumped the radio into a position of extreme im portance. Already, In various parts of the country, cities, recognizing the pub lic demand for entertainment, are arranging for municipal plants at which regular programmes will be give at stated hours for the lis tening thousands. , Starting - with the simple trans mission of phonograph music, the broadcasting field haa "enlarged to the educational. At the present time the- radio is being used for operatic concerts, lectures, courses of home instruction in various sub jects from nursing to home econom ics and psychology. No private corporation cart be de pended upon adequately to meet this public demand, and the burden is gradually , being assumed by the public agencies on whom always fall the responsibility of educative functions. , New York is the first city of its size in the world to erect a munici pal broadcasting plant. It intende to spend thousands of dollars for the new station, and New York's pioneering in this regard will prob ably be followed by other cities. At the present time public de mand is for better music, better radio service and better standard izing of features. The suggestion recently made to employ radio in the teaching of Es peranto, while it may lead to no def inite results, nevertheless opens an interesting avenue of speculation as to the advantages that would accrue if there were an international lan guage which would tie up all coun tries using the radio telephone, and the further thought that radio could be usefully employed in disseminat ing such language. In other words, it furnishes both the impetus and the means toward what many interna tional thinkers have always consid ered a highly desirable end. There can be no doubt that if ra dio enthusiasts in other countries share the temperament of the ama teurs in America they would go in seriously for the study of such tongue If It would help in the pur by Einstein's theory of relativity, which is now meeting general ac ceptance. The mistake which led to the hy pothesis of the ether was that wave motions were the only waves known at the time when the theory of light was proposed, and so the light wave also was considered as -a wave mo tion, and the question asked, what moves in the light wave and this moving thing called the ether. Since that time, we have long become fa miliar with waves which are not wave motions, but merely periodic phenomena. Thus the alternating current is a wave, but nothing ma terial moves in it. Thus we speak of waves of temperature, etc., with out meaning any material motion. The radio waves and light, waves" are electro-magHetic waves; that is, periodic variations of the electro magnetic field in space. The space in the neighborhood of a magnet is different from ordinary space. It contains magnetic energy and exerts magnetic - forces on bodies susceptible to them. It is called a magnetic field. That Is, it contains stored electric energy and exerts electrical forces on bodies susceptible to them. An electric current produces a magnetic field. A voltage produces an electrio field, and as current and voltage usual ly occur together, an electric cir cuit gives a magnetic and an elec tric field, thet is, an, electro-magnetic field. If voltage and current are con stant, their electro-magnetic field is constant, if current and voltage suit of their hobby. Radio knows no limitations of boundary, and if the amateur could push his range of communication into countries out side his own, he would be quite like ly to attempt to learn even another language than his own. , Just what the exact effect of John Hays Hammond's recently announced discoveries in wireless communica tion will be is as yet a matter of guesswork more' or less; but they are certain to be revolutionary, if they live, up 'to the first announce ments. Mr. Hammond claims that his in ventions will both make secrecy pos sible, by preventing any station from taking messages except those in tended for it, and also enable sev eral messages, both code and voice, to be transmitted on the same wave. . If th,e inventor's hopes are justi fied, radio will assume a place in communication that its most opti mistic supporters had not yet dreamed possible. All the advan tages of the broadcast will remain intact, and in addition personal communications, both business and social, will be made easy -withoait Interfering with the broadcasting of each other. At the moment it hardly seems possible that the wireless can be perfected further than that, but experience of the past, few months has shown that any predictions as to radio's limitations are likely to be rendered absurd within the next few months. Plans for direct wireless commu nication between Australia and Great Britain have been announced and will provide for a main station which will be able to speak over 12,000 miles for tne greater part of the day. The site -for the station has not yet been selected, but it will either be in New South Wales or Victoria. Six feeders, one in each of the capital cities, will work with this main station, and as far as pos sible, the radio system, which is to be taken over by the common wealth next month, will be utilized for this purpose. Several new plants will also be required. ' The camper who wishes to take a radio set with him on his vacation, and wants something better ' than' the crystal type, will find an almost made-to-order substitute in the vac uum tube receiver now on the mar ket and which uses only one dry cell for the lighting of the tube fila mentj. The ordinary vacuum tube receiver employing a storage bat tery presents a knotty transporta tion problem. It would take a mighty , ambitious camper to tackle this load unless he has an auto to carry the whole outfit. The single dry cell vaOUm tube receiver is ideal In every respect. If it is taken along on the trip, two or three ex tra dry cellsshould be carried along. If a fresh "B" battery is taken along it will probably last for the dura tion of the trip. . company, by radio. presenting vary, the , electro-magnetic field varies; if they alternate, the elec tro-magnetic field alternates and such an alternating electro-magnet ic field we call an electro-magnet ic wave. 1 If it alternates about a million times per second, this electro-magnetic wave is a radio wave like that through which I speak to you; If it alternates many hundred millions of millions of times per second, it is a beam of light. ' Thus the radio waves and the light ray are electro-magnetic waves; that is, alternating electro-magnet ic fields. Now an electro-magnetic field is a storage of electric and magnetic energy in space, which ex erts electric and magnetic forces. This energy must be supplied from the source of the wave, and this takes time, so that the electromagnetic- wave cannot appear in- stantlv all throuerh SDace. hut must. gradually progress at the rate re- quired to fill up the space witn electro-magnetic wave energy, and this gives the velocity of propaga tion of the electro-magnetic wave SOO.fiflO.OOO meters per second. ' Thus the radio waves ' and the light rays are electro-magnetic waves;, that Is, alternating mag netic fields; there is no such thing as the ether, and if in the attempt to be progressive we talk about ether waves and ether telegraphy, we are just the opposite, are be hind the times. Thus let us stop talking about telegraphing through the ether, and rather speak of tel egraphy by electro-magnetic waves. Radio Station Is Planned For Lancaster Camps. Powerful Receiving Plant Will Serve Outing Parties.; AN illustration of the widespread adoption of -radio is provided in the fact that a receiving station is to be installed at Lancaster's Columbia Gorge comp and in other Lancaster camps in the heart of the Cascade mountains. The instrument which is to be erected at the Columbia Gorge camp, near Eagle creek, on the Co lumbia river highway, has been in stalled'in the armory here and wiy provide entertainment for the vis itors to the Chamber of Commerce exhibit to be held this week in conjunction with the Rose Festival. The station is equipped with a magnavox, and is powerful, capable of receiving concerts and messages from all Pacific coast broadcasting stations. A need long felt in the mountains will be supplied through the in- Lectro Crystal Detectors Most efficient, easily adjusted detector on market glass enclosed. Price $2 each." Ask your dealer. TRADE UI ! Lectro Mfg. & Sales Co. 331 Oak St, Portland, Or. Manufacturers and Jobbers Radio Supplies RADIO SUPPLIES Immediate deliveries, standard goods. - Dials, headsets. American Beauty receiving sets, variable condensers, transformers, rheo stats, varlcoaplers, panels, tubes, etc. Dealers' attractive discounts. Write for price list of COMPLETE LINE. American Radio Mfg. Co. Jobbers. MeGee and Admiral Blvd. Dept. M, Kansas City, Ho. PNI IMC who is presenting; new We are manufacturers of the Best Crystals, Mounted and Unmounted. Positively Sensitive. Sold with Guarantee. Insist on U. 8. Crystals, everything In Radio Supplies, t. 8. RADIO CO. OF PENNA., Inc. Ferry and Diamond Sta.. Pittsburg, Fa. -- v . . - stallation of the radio stations at the camps at Eagle creek. Lost lake and Wahtum lake. Heretofore campers in the mountains have. been practically cut off from communi cation with the outside world, and in times of emergency much hard ship has been wrought. Now per sons can camp in the deepest wilds and yet be within an instant's com munication with members of their families, hundreds -or even thou sands of miles away. Arrangements have been made by Samuel G. Lancaster, founder of the camps, with local broadcasting stations for the transmission of emergency messages to the guests at camps. The radio stations erected at the camps are among the first to be installed at mountain camps on the Pacific coast. It is believed that the venture will prove popular and successful, and that it will be gen erally adopted throughout the country. , Radio Notes. ACCORDING to the latest inform atlon obtainable from the gov ernment, 25 newspapers in the Unit ed States have installed radiophone broadcasting stations. They are as follows: Atlanta. Constitution, At lanta, Ga. ; Atlanta Journal, Atlanta, ua.: Canton Daily News, Canton, Ohio; Daily States Publishing com pany. New Orleans, La.; Deseret News, Salt Lake City, Utah; Detroit Free Press, Detroit, Mich.; Detroit News, Detroit, Mich.; Herald Pub lishlng Co., Modesto, Cal.; Los An geles Examiner, Los Angeles, Cal. Modesto Evening News, Modesto, Cal.; Newburgh News Printing com pany, Newburgh, N. Y.; Newspaper Printing company, Pittsburg, Pa.; oregonlan Publishing company, Portland, Or.; Palladium. Printing company, Richmond, Ind. : Pasadena Star-News company, Pasadena, Cal.; rost-jjispatch. St. Louis, Mo.; Reg ister - and Tribune, Des Moines, Iowa; Rtdgewood Times Printing & Publishing company; Rochester Union, Rochester, N.- T.; Spokane Chronicle, Spokane, Wash.; Seattle f OBt-lntenigencer, Seattle. Wash. San Francisco Examiner, San Fran cisco, Cal.; Telegram Publishing company, Salt Lake City, Utah; Tri bune Publishing company, Oakland, Cal.; Tacoma Ledger, Tacoma, Wash. Radio has added another aid to the agriculturist. For some months government and other agencies have been broadcasting special informa tion for farmers regarding weather markets and atmospheric conditions that have proved a great help. Re cent experiments have shown that the crops of farms in the vicinity of high-powered radio stations have been affected by radio waves. It has been discovered that the waves from these stations have had a most ben eficial influence upon vegetation in the vicinity, causing it to take on a larger growth, reaching its ma turity sooner than under ordinary conditions and greatly adding to its weight and size. It was specified that vegetables close to the station grew more rap idly and sturdy than those situated at a farther distance from it. At Honolulu an experiment station has been installed and the theory that wireless waves can he used with satisfactory results in general farm ing is the subject of research. It is believed that by distributing the wireless wave close to the ground and over a wide cultivated area an inexpensive ami practical means may be developed for furnishing - n: l -"io uuicr aim energizer to i a large area , farm countrv from - I central wireless station. It has been proved that by this method the growing season of most crops 1 can be considerably shortened and ' at the same time an enormous yield produced. A theater In Des Moines, la., will only have that music provided by Chicago, Pittsburg and Denver by the medium of a highly amplified receiving set now being installed. This will probably bring forth a storm of protest from the musicians' unions as did the broadcasting of popular songs from the publishers and the broadcasting of theatrical performers from the Equity asso ciation. The music will be as good, regardless of the interference and effect of atmospheric conditions as the usual "piano banging" of the small movre house. It might be a little inconvenient, however, if the broadcaster starts sending out some jazz just as the hero gasps his last, etc. SEE THE NEW GENERAL ELECTRIC SET now being demonstrat ed daily between 1 and 6 in our store. Come . in and hear the broad- . casting. ELECTRIC CO 75 6th St. Portland Selling Radio for 10 Years Mail Orders Filled Chown Hardware Co. . 147 Fourth Street I 1 fi ft PUPIL IN MANUAL TRAINING WINS PRIZE FOR RADIO SET William C. Ellis, Expert at Tuning, Makes Unique Outfit With Cigar Box at Small Cost to Himself. ' r' j 11,1 11 Mysraz William C. Bill, winner of the ' receiving et he made from a digar the bnilder the prize. A CONTEST for the best home made radio receiving set turned out by the boys taking the manual training work at the Arleta school, was recently con cluded. William C. Ellis, 5411 Sev entieth street Southeast, won the prize with a cleverly made set con structed out of a cigar box. The actual cost of the set is very little, as young Ellis used a lot of brass screws for switch points and metal scraps for the other units of the set such as the detector and con denser. The young radio fari has already made a number of radio sets and Protect Your Home and Receiving Set Just As Your Telephone Line Is Protected From the INSIDE Use a Permits Inside Use National Underwriters lave ruled that automatic wfety features of the ) 9obns permit Inside ln rtallatlon the way the protector on your tele thon line is Installed. $2.00 From All Good Dealers APEX ELECTRICAL 17 Ornnse St- Ship Owners Radio Service Broadway 1931. J. B. WEED, Manager. 310 Oak Street. rmnTc i Beautiful finish panels. Black, brown and mahog anite. Best insulation tor radio, resists warping. Standard Dials 3 tn. and 1 in knobs, eockets. bases, etc. Dealers write GOODYEAR RUBBER CO., Pacific CoaHt Aaenta Portland - - 1 Fourth St. American Hard Rubber Co. We Are Catching Up Investigate the New "SR22" "Northwestern" ' Receiver For Distance Work . Hallock & Watson .' Radio Service . 192 Park St. Portland, Or. Arleta school radio content, and the box and brass scraps which brought has become an expert at turning out efficient outfits at a very small cost. Following the conclusion of the school contest, young Ellis was asked by a local department store to demonstrate to the public; how a simple radio set can be made. He spent a whole day in the store mak ing the sets out of cigar boxes and a few ecraps of brass, while nun dreds of interested folk watched him. , . . - Ellis declares that he'd rathe make his outfits in his own home than where there are a lot of peopl around asking a lot of questions. JACOBUS VACUUM Aerial Protector No Groand Switch Carries off all statio ind lightning automatlc illy -without damage to it lelf or interference ' with four set. Protection every minute of the day and night. Underwriters ap prove the Jacobus to re place ground switch. Use i Jacobus, the best form f lightning protection. SPECIALTY CO., INC. Newark. N. J. Stock Situation IMPROVED! We can make imme diate delivery on practically all radio equipment. Complete Installatiom If Dealred. i Installers of Oresonlan Radiophone) E.L.Knight&Co. 449 Washington St Near 12th. Broadway 145. Just received the new Western Electric two-etage amplifier and Loudspeaker REDUCED PRICES 2-Stage Receiver, complete, C240, NOW 2O0. Concert Every Saturday Night. "KNIGHT MAKES DAY-THE ELECTRIC WAY" WE HAVE RADIO SUPPLIES ALSO A FEW . HEAD SETS BETTER COME EARLY 'SMITH-McCOY ELECTRIC CO. 264 ALDER ST-MAIN 8011 'Buy Electrical Goods From People Who Know"