Evening Star Newspaper, June 19, 1922, Page 17

THE EVENING STAR, WASHINGTON, D. U, MONDAY, JUNE 19, 1922. ! € Zy s BY A. HYATT VERRILL. Expert on Radio Technology. The crystal detector set seems to be the prime favorite of beginners. But its range is limited, it is difficult to adjust the crystal contact twice alike, and the novice soon tires of experi- menting with & crystal set and dis- cards it in favor of the tube set. Ordinarily, if an amateur wishes o “improve® his crystal set, he adds ® loading coll to receive longer waves, #dds a variable condenser to shorten them, installs a loose-coupled coil or & varlo-coupler with two or three wwitches and ten to twenty centact points, and in the end has a cluered up set with a multiplicity of controls and adjustments. With every set, whether crystal or #ube, the aim should be simplicity and the more the number of con- trols can be reduced without losing #harpness and differentation in tun- ing the better. 1If you wish to have & wide range of wave length recep- tiveness it is far better to have a very long inductance with sliders 1han a tapped coil or a short coil with Joading coil. With a slider every turn of wire may be used, hence much finer and oloser tuning may be ac- complished. With a two-slider cofl, using a fixed secondary and with a ~arlable condenser, very sharp tuning nd a great variation in wave lengths 3 possible. Even slider colls have objectionable features. In the first place, such & cofl must be mounted ©on the outside of a cabinet in orde: 10 operate the sliders. In the secon lace, the sliders, rubbing upon the vires of the coil, grind off tiny artioles of metal which short circuit he turns of wire, and in the third place, after long use, the contacts be- coms worn and loss of current re- #ults. But by using a variometer and e varlable condenser all these ob- Jectiond are eliminated. Variable Condenser Useful. Tndee@ few people realize what an extremely useful and efficlent device tie variable condenser Is or its value as a tuning instrument. With & properly arrange set, either crystal ‘or tube, all other tuning devices may le eliminated, but, even without do- ing this, wonderful results may be obtained by the proper and Intelli- gent use of variable condensers. It must be borne in mind that load- ing coils decrease the strength of signals brought In, and that, when using a coupled tuning device on the ot the loading coil should be cou- pled in the same ratio if best results are to be obtained By adding a Joading coil you a merely increas- ing the size of the coll ordinarily used and are adding ments, but by densers to le wave receptive number of to the adjust- using variable con- gthen or shorten the ss of the set the adjustments may be de- creased, while the normal coil size remains constant. although, of course, the strength ing oscillations will be som reased. If you desire longer agths the con- denser should :od parallel or across the 1, where- ns. it you g E ve lengths, it should be placed in series with the aerial cire g, 2, thus, by using 2 long inductance With a variable condenser in series the normally long viave length may be cut down at will By using a short inductance, the no: mally short waves received may be increased by a condenser acress the inductance, as iliustrated in_ the drawings. However, this necessitates the use of two condensers, which adds to the multiplicity of Instru- ments, and stiil further reduces the strength of the currents. But by so arranging the condenser that by merely throwing a switch It may be used olther In serles or across, sim- plicity is galned without reducing the wave length variability of the sot, Fig. 3. Then. by placing a single varlometer In the circuit very fine and accurate tuning may be secyred, Fig 4. The greatest drawhback to the crys- +al set is its lack of sensitiveness and the difficulty in securing a particu- Jarly sensitive crystal or the same =ensitive spot on the crystal twice. The most important thing, 1f crystal seta are to be fmproved, is to in- crease the senitivity of the set so that very wezk signals may be re- celved and at the same time secure a contact with the crystal which is not readily jarred or vibrated off and does not requlre constant puttering and readjustment. Galena Most Sensitive. We are so accustomed to using galena crystals and a catwhisker for crystal detectors that few beginners reallze this Is by no means the most sensitive or satisfactory type of crys- tal detector. Many other crystals we all know possess the same prop- erty of cutting oft one-half of an al- ternating curren., thus acting like a wvalve. But none of these, so far as we know, are as sensitive as galena under ordinary conditions. The best known of such crystals is carbrundum and by electrifying a carbrundum crystal it can be as sen- sitive as the best galena by varying the current of electricity passing through it. Therefore, by adding a small battery to a crystal set and substituting carbrundum for galena the set may be made more sensitive + and the strength of the currents in- creased as well (Fig. 5). In fact, such _an arrangement may be com- yared, in a broad sense, to the radio frequency transformer in a tube set. Not only does the carbrundum thus ireated Increase the sensitiveness of the detector, but by its use the deli- cate cat- sker contact may be eliminated, for a blunt steel or metal point, such as a knitting needle or a stiff wire, should be used for a contact and as this should be pressed firmly against the crystal. There isno danger of its being jarred loose, as in the case of the famillar cat- whisker. By fixing this contact point in a set screw, as shown in ¥ig. 6, very fine and accurate ad- justments may be secured. Do not imagine that you merely have to con- nect a dry battery to your circuit in order to make the outfit work satls- factorily. The entire success of the electrified crystal depends upon the regulation of the current flowing through it and in order ‘to permit of n fine adjustment of current a poten- tiometer must be used. This is & rimple instrument, no more compli- cated or difficult to make than an ordinary grid-leak. In principle a potentiometer is merely o varlable resistance and any resistance snaterixX, ‘such as graphite or German pilver wire, mmy be used in its con- struction. Simple Form Potentiometer. A very simple form of potentiometer ~which will do yery well for experiments consists of a rod of graphite placed ‘hetween two terminals or blnd]na“DMI and ded with a simple metal clip a carpenters’ ll::: pencil 8 9 & carpenters pencil (on !fl:o:swkhn.brud.flnll-a)ln i 2 it s better to make one by using & Ct aw Iver wire. 'fl“g— »ing it with a siider upon a rod exactly L o muar pecewer AND TRIFLER!! ~ : Zy2 BY RADIO TODAY Complete Programs of Radi Broadcasting Stations. as in making a tuning coil. However, L/ unless you are familiar with electrical work and are able to compute the size of the coil and the number of turns and size of wire, by all means go to your dealer and buy & ready-made in- strument of from 150 to 400 ohms re- sistance. The batteries to be used are ordinary dry batteries and, until you have de- termined just the right amount of cur- rent necded for best results, it is well to use several connected in series. Then, by cutting out one or two at a time, you can find the best number suited to_your set. Connect up your set—it makes no dif- ference what circuit you use, whether single or double, or what tuning devices you employ, as shown in Fig. 5, put the phones on your ears, set the poten- tiometer at the highest resistance point, screw down your contact on the crystal until it presses firmly upon the latter and slowly move the potentiometer ad- Justment until you get signals. Then tune in to those you wish to hear. Ad- NAA—Naval Radio Station, Radio, Va. 10:30 a.m.—Meteorological report on 5,950 meters of arc transmitter. Noon and 10 p.m.—Time signal, fol- lowed by weather report and ship orders. 10:30 p.m.—Naval press news; wave length, 2,650 meters. WWX—Post Office Department. 10 a.m.—Weather réport for the District of Columbia, Pennsylvania, Ohio, Maryland, Virginia and West Virginia. / 10:30 a.m—Marketgram (fruit and vegetables) on 1,100 meters. 12:30, 2:15 and 3:30 marketgram telegrams on ters. Just the potentiometer until you secure | 1553':;3;‘;:"1;))"?35?0::(‘\?;. report on thie wry Dest Fpulin "7:30 and §_p.m.—Market report on (Copyright, 1922.) —_— SIGNAL CORPS RADIO GETS PART OF STATION Arlington to Be Chief Sending Location Qut of Capital. $50,000 Is Saved. Through the co-operation of the naval communications service, the radio section of the Signal Corps June 5 acquired the use of part of the big Arlington station for its chief sending station out of the capital. Two sets will be used by the Army exclusively, one tube set with ten kilowatt, and another with twenty kilowatt in the antenna. The latter, used on about 3,000-meter Waves, should carry as far west as Omaha. Today the Signal Corps is using a two kilowatt tyansmitting set at Arlington for regular traffic on 2,630 meters, controled from the radio headquarters in the Munitions build- ing. The government has saved at least $50,000 by combining the naval and Army sending stations at Arlington, it is said, as the Signal Corps station planned for the Washington barracks would have cost practically that much when the permanent installa- tion was completed. Now the tem- porary station at the barracks has been abandoned, and the permanent construction saved. The Navy will still continue to operate from its station at Arlington, using its own sets, as previously, but has arranged to lend the Army radio section its big 100 kilowatt spark set when necessary, as well as its arc set. Another combination has made possible the operation of the Navy one kilowatt tube set at Arlington by either the naval air station at Anacostia or the Army Bolling Field for the transmission of messages to planes or short distances up to 250 miles. These stations will also con- duct considerable meteorological work with the one-kilowatt set at Arling- ton. SULTAN'S PRESTIGE 1,160 meters by radiophone. 9:50 p.m.—Weather report. WMU—Doubleday-Hill Electric Com- pany (360 Meters). 4:30 to 5:30 p.m.—Base ball scores announced. “Sweet Indlana Home' (Walter Donaldson): ‘Moon Moths," piano (Kussner); “Timbuctoo” (Kal- mar & Ruby); “Drowsy Waters “The Old Refrain,” piano (Kreisler); “National Emblem March” (E. E. Bagley); “Otello,” barytone (Chopin); ‘Nooturne,” plano (Walter Donald gan & Whiting); “Swanee Blu bird' (Cliff Friend-Con Conrad); *“Magio Fire Scens,” plano (Wagner- GONE,FAREREFINDS Constantinople Sulks French Novelist Ac- claims Caliph. BY CONSTANTINE BROW By Cable to The Star and Chicago Dally News. Copyright, 1922. CONSTANTINOPLI June 13.—The wane of the sultan’s power, as well as his unpopularity with his subjects, have been more conspicuous -since the arrival of the French novelist, Claude Farere. He was glven a wonderful re- ception in the caliph’s capital, was in- vited on Wednesday to a dinner at the town hall, in front of which a huge crowd gathered. calling for a speech. Farere appeared on the balcony and made a speech to the crowd below, but when he ended the address with the traditional shout, “Long live the sul- tan!” the people became icy cold and dispersed sulkily. The Turkish people, as well as the tmperial family, hoped much from Fa- rere’s visit. The sultan received him in a long audlence and asked him to 80 to Angora and use all his influence to convince the nationalists that Tur- key's salvation depends entirely on blind obedience to the sultan, who ‘is the prophet's representative on earth, and that the Mohammedans would | never make any profress until the ab- | soluto authority of the caliphs was re- established. M. Farere, after his experience at the town hall, thought it wiser to ex- | plain to the sultan that pfessing busi- | ness required his presence in Parls, £o that he would be unable to make the ! Angora trip. ‘Turkish gubllc op?aion | hoped to get favorable publicity through the French writer. It was thought that he would try to prove to the world that all thus far written against the Turks was slanderous propaganda. REBEL LEADER SLAIN. Fifteen Mexicans Reported Killed as in Battle in Oaxaca State, MEXICO CITY, June 19.—Mario Ferrer, leader of the rebels in Oaxaca state, was killea Saturday at Tiite- pec, in that state, according to a parently authentic dispatches receiv- ed here from Oaxaca. The reports say Ferrer was killed in a battle with government forces led by Gen. Fortunato Maycotte. The rebel losses in the fighting, which lasted one hour, are given as fifteen dead and elghteen wounded, while no federal losses are reported. Ferrer's bedy was hidden by his followers in the jungle, according to the dis- patches, but was found by the troops. The death of Ferrer, if confirmed, remeves one of the most important rebel leaders in southern Mexico. He hasebeen active for the past month in behalf of Gen. Diaz, and his forces are said by government officials to have been responsible for the recent blowing up of & pasgenger train carrying & military convoy at Temol- 1lin, between Puebls and Oaxaca City, in which twenty-five persons were killed. _— The bones of & human being will bear three times as great a pressure as osk and nearly as much as ‘wrought {ron without being crushed. . "Scandinavia” (Ray Per- ‘Aloha Oe" (Lil- " plano (Rach- tripes Forever Mirandy" Brassin) kins-Edgar Carber) oukalini); “Romance, maninoff); “Stars and March” (Sousa); “Buzz, (Dave Franklin-Henry ~ Creamer); “Blue Danube Waltz,” piano (J. Strauss). Base ball scores announced. WEAS—The (360 Hecht Company Meters). 3 to 4 p.n—Music; retail news and reports. S \ WPM—Thomas J. Williams, Inc. (360 Meters). 12:30 p.m.—News items; reports on stolen automobiles. 8.p.m.—Duo Art piano selection, played by the Duo Art reproducing plano; George Paxton, reader; Kcetha Fay Paxton, harpist; Jack and Margaret Mullane; Mrs. Selma Selinger Kline, accompanied by Mr. Kline; Francis and De Mar; Dan- iel Breeskin, accompanied by Amella Olmstead—(a) “Cavatina,” by Raff: (b) “Smilin’ Through,” by Arthur Pence: (c) “Hungarian Dance, No. 5" Erahms; solos by Mr. and Mrs. Wallace. 8YN—National Radio Institute (300 Meters). dio spark code. WVP—United States Signal Corps, Bedloes Inlpnd, N. Y. (1,450 Meters — Daylight-Saving Time, Deduct One Hour). 8:50 p.m,—Instruction in radlo. 9 p.m., concert under direction of Charles Isaacson. WGI—Amrad, Medford Hillside, Mans. (360 Meters—Eastern Daylight- Saving Time—Deduct One Hour). 2:556 p.m.—News and muslc. 7:30 p.m.—News and music. You SAID YOU WERE PLAYING GOLF TODA TELL ME,-DO YoU PLAY WITH LIP STICKS, HAIR-NETS AND DAINTY KID GLOVES ? l Coppright, 1922, by The MeClre Newrpaper Syndicats. 17 BY JACK WILSON. S0 ‘l*‘ % TAKWTLSON— G-r9 “The Modern m.—Agricultural reports and prices as released by New York, New Jersey and federal bureaus; program of music. m.—Program of music; tal, 9 to 9.15 a.m.—Muslc. 11:30 a.m. to noon—Muslc. :30 p.m.—Base ball scores by in- nings. 6 p.m.—Weekly survey of business conditions; base ball scores; theatri- 8 p.m.—Lecture on Novel 8:35 p.m.—Concert. WWZ—Wanamaker" (360 Meters— E: New York City tern Daylight- Duo Saving Time—Deduct One Hour). |cal features. Noon—Agricultural reports; weath- | 1:40 p.m.—Brief song recitals. 6:45 p.m.—Special news; government | er forecast; program of music; Duo 4:40 p.m.—Children's hour given by |market reports; summary of the New | Art recital. Elsie Jean. Subject: “A Misunder-| York Stock Exchange; weather re- 12:15 to 1 p.m—Standard time sig- nals from Arlington. 1 p.m—Program of music. 2 p.m—Shipping news; program of music 3 p.m.—Program of music. 4 p.m—Base ball scores; women's 55 to 10 p.m.—Arlington time| fashion news; program of music. signals. 5 p.m.—Base ball scores; program of music. (o12:30 p-m—Early stock market quo- e e st aa T Al T e it oAl el BimProduce and stock market| ime,Seme as Eesters Stndant| 000 goara) Weathor Torecast quotations; ; 525 Am—Opening market quota-|SETicultural reports; shipping news: tions, Chicago Board of Trade. p"_‘?xfm_(:: music. 10 a.m.—Market quotations at one-| 7 P.m—Children's stories. half hour Intervals until 1 p.m. 7:30 p.m.—“Esperanto.” a suggested 1:20 p.m.—Closing market quota- port. 7 p.m.—“Summer Sports” by C. 8. Garland, tennis star. 7:30 p.m.— Bedtime standing. 10:30 p.m.—WWZ's health college, conducted by Mrs. Anna H. Delavan, physical director of the American Red storfes for Cross. Subject, “Habits and Life Brief program of music. —A variety of vocal and in- WGY — General _ Electric Company, Schenectsdy, N. Y. (360 Meters— Eastern Standard Time). WWJ—Detroit News (Eastern Stand- ard Time). 9:30 a.m.—Tonight's dinner household hints (360 meters). 9:40 a.m.—Music (360 meters). H 10:15 a.m.—Weather report (485 meters). 11:55 a.m.—United States naval ob- servatory time signals relayed by telegraph (360 meters). 12:30 p.m.—Music (360 meters). 30 p.m.—Weather report (485 me- ters). 3:40 p.m.—Market quotations (360 meters). 6. p.m.—Complete sport world news (360 meters). 8:30 p.m.—Special concert by De- troit News Orchestra (360 meters). international adio language by James Denson Sawyers of the New S Newsland mierket | York_Evening Post League base ball team line-ups: pog- | From the Cocoon to the Silk Gown, ress of games every half hour there- [ b¥ Carolyn T. Radnor-Lewis of New until their close. 105”;; e B R market and stock |, J . Command Band of New York of forty pieces. 9:15 p.m.—Concert by the Upsilon Fraternity Glee Club. 10:32 to 11 p.m.—Arlington signals. 11:01 p.m.—Weather forecast. and ; final market and base ball reports. Delta dren’s bedtime story. time § to 9 p.m.—Program of music by the Montgomery Ward Chorus. 9 p.m.—News and sports. 9:05 p.m.—Special features as an- nounced by radiophone. resuits; WBZ — Westinghouse, Springfield, Mass. (360 Meters—Eastern Day. ight-Saving Time — Deduct One Hour). 7:30 p.m.—Base ball scores; time stories for children. EKDEKA—Westinghouse, East Pltts- burgh (360 Meters—Eastern Stand- ard Time). ‘WJZ—Westinghouse, Newark, N. J. (360 Meters—Eastern Daylight-Sav- ing Time—Deduct One Hour). bed- The Coca-Cola Company 0. Atlanta.Ga. 45 p.m.—Lecture and market re- ports - { % pm.—Program | ball score. of base music; WGR—Federal Telephone ph Company, Buffalo, X astern Daylight-Saving Time— Deduct One Hour). om—Weather and market reports 5 meters). 5:30 p.m.—Weather and market re- ports (458 meters). 8 p.m.—Base ball scores, bedtime stories for children; digest of day's news (360 meters). §:15 p.m.—Concert by Federal Tele- phone and Telegraph Company (360 meters). —_— COAL DELIVERIES DROP. ermany Getting in Arrears Meeting War Obligations. BERLIN, June 19—The reparations commission has notified the German government that coal deliveries of lats have been considerably in arrears of ions, especially during will discuss the th the guarantee committee, which is now on its way here. 1t is understood that it will be pointed out to the eagumittee that German pro- duction h eatly decregsed, that there is a shortage of coal for domestic consumption, that the aigh rate of ex- change precludes the importation of coal and that the labor ministry is at pres- ent negotiating with regard to the ques- tion of overtime work in the mines. _ L in There are five rivers in the world which drain nearly 1,000,000 square miles. They are the Amazon, La Plata, Obi, Kongo and Mississippl