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About The Sunday Oregonian. (Portland, Ore.) 1881-current | View Entire Issue (Dec. 17, 1922)
11 TELEPHONE RECEIVERS ARE IMPORTANT UNIT IN RADIO SET ''" ' 11 ' I . .1 I ' I - - ! I I.- IB .-HI. 'I . - ' Addition of Efficient Head-Set Greatly Increases Sensitivity of Outfit Phones Must Be Made Accurately and With ExtremeXare Fans Told 'What Features to Expect in Making Purchases Interest Greater. THE SUXDAY OREGONIAX, PORTLAND, DECEMBER 17, 1923 r BY SAUL EMANUEL. YOUR pair of telephone receiv ers is an important unit of your receiving set. As your phones are, so will your receiving set be, in its degree of efficiency. With a poor set of phones the best receiving set will give only fair re sults, while if a good head-set is added to only a fair receiving out fit, the sensitivity of the outfit will be greatly increased. Because only very small currents of electricity operate a receiving set, the phones must be made ac curately and with extreme care. When purchasing them, the fan should look for the following fea tures of a well-made head set: The winding of the magnets should be of from 2000 to 3000 ohms resistance for the two receivers to obtain the best results. The term "resistance" used as a standard of measurement for telephone receiv ers is often misleading to the radio novice. In reality, what the fan should look for in a receiver is the number of ampere-turns about the magnet It is upon these that the strength of an electro-magnet is dependent. An ampere turn Is one turn of wire, through which there passes one ampere of current. The total number of ampere-turns in a tele phone receiver is the number of turns multiplied by the current passing through in amperes. Resistance is another thing. A receiver may be wound with a few turns of high resistant German sil ver wire and it will be rated at so many thousand ohms. But the am pere turns of such a receiver will be very few and the receiver will be practically worthless. As receivers of this kind made by unscrupulous manufacturers some times appear on the market, the fan should take care to purchase only when it is known that the magnets are wound with copper wire. Another important feature to con sider when purchasing telephone receivers is the type of diaphragm they contain. In all head sets with metallio diaphragms these are de signed to vibrate best at a certain frequency. For the reception of broadcast speech and music, those receivers which are designed to re spond to vibrations around 250 cycles will reproduce the broad casts with the clearest modulation. The mica diaphragm receiver is considered as one of the'most sensi tive known today. Its construction differs a good deal from the ijthers, in" that the vibrations of the dia phragm are caused by means of an armature responding to the changes in strength of the magnetic field around the magnets. Owing to a slight leverage action of this arma ture attached by a pivot to the dia phragm, signals are amplified in the receiver itself. The telephone receiver is a deli cate piece of apparatus. It Is very easily injured if it is knocked about or dropped on the floor. Receivers should always be hung up on a hook when not in use. You've noticed, of course, that when you pull the diaphragm away from the magnets, it clings quite strongly to the magnets. This Is due to the permanent magnetism in the magnet cores. All receivers- are permanently magnetized. In time this magnetism grows weaker and the phono becomes less sensitive. When this occurs the re ceiver should be remagnetUed. This can be done by sending it to the manufacturers, or if you ha"ve 110 volts of direct current in your house connect the head-set across the power line for a few moments.. Care must be taken, however, that the current Is passing through in the correct direction, otherwise the magnetism will be destroyed en tirely. Value of Radio to Nation to Be Emphasized. Week to Be Dedicated to Adver tising Programme. THE extraordinary value of radio broadcasting to the educational, j religious and recreational life of our country is to be emphasized during a national radio week, to be held I everywhere from December 23 to 30. During this week every one en gaged or interested in radio will en deavor to demonstrate to the un initiated the wonders and benefits of this newly developed branch of science. The effort to establish national radio week as an annual institution is backed by co-operative effort on the part of the newspapers, the radio press, manufacturers, dealers, amateurs and the great army of broadcast listeners, whose numbers are legion. The tentative programme arranged for the week, December 23 to 30, inclusive, is the most com prehensive plan ever undertaken to popularize radio with the great American pirblic, and while only a general outline of the plan Is so far available, it is known that it embraces programmes of nattonal, state and local character. In which the Bo0 or more radiophone broad casting stations of the country will ake an active and important part. Special programmes to include the leaders among public officers, statesmen, educators and the mu sical and entertainment world in general are being arranged, all with the main idea of introducing radio to the uninitiated and firmly estab lishing it in its proper place as a recognized agency of bringing radio instruction and entertainment into the homes of the nation. The plan to hold national radio week started a few weeks ago at a meeting in New York city which was attended by 20 editors and pub lishers of radio publications. It grew so rapidly that before they had left the meeting an executive committee had been appointed, with J. Andrew White, editor of Wireless Age, as chairman. . With him, serving on the com mittee, are Arthur H. Lynch, editor of Radio Broadcast; H. Gernsback, editor of Radio News; Laurence Nixon, editor of Radio Dealer; Roland B. Hennessy, editor of Radio World; and Arthur H. Halloran, editor of Radio. Aiding this committee Is a gen eral committee, and on the latter are the names of the editors of ANNOUNCEMENT TO DEALERS We are now distributing the famous "Kellogg" Ima ff T?Qirt A T"ro vo -11 o .1 Wl a.VCfrVAJ.V ilMabUO HALLOCK & WATSON RADIO SERVICE 192 Park Street, Portland, Or. Broadcasting Station KGG Experimental Station 7X1 u BLIND AT WASHINGTON STATE SCHOOL ENTERTAINED AT BEST OF OPERAS THROUGH INSTALLATION OF RADIO SET .. .. ; . " ' . : New Field of Enjoyment Opened to Students at Vancouver Institution and Many Tedious Trips to Portland and Other Cities Are Avoided Since Musical Programmes Now Can Be Had at Any Time and Right at Home Demand for Set Great. fgSJx- i 0$M h h "forth STUDENTS OF THE WASHUVGTOJT T TANCOUVER, Wash., Dec. 16. 1 ANCOUVER, Wash., Dec. 16. V (Special.) To most folks ra- (Special.) To most folks ra dio is just a novel means of - 1 entertainment the alternative to a trip to a movie or theater. But to students at the Washington State School for the Blind, whose activi ties are necessarily jnore limited than those persons in full posses sion of their sight,, radio opens up an entirely new field and another meani of contact with the outside world. The blind students love mu sic and they seldom miss an oppor tunity to hear a concert or an opera. But the piloting of a large group of students to Portland during the many newspapers and radio period icals. The main purpose of National Radio week is to double the number there are now a million Exact 1 ?0ToPaV a crystal set figures are impossible, ana s. nui- 1 using- a vario-coupler, variable conden lion is probably conservative. But ser, fixed condenser and galena detector ? if each of these listeners will in terest at least one other person, the number -will be doubled, and the resultant good to radio will be inestimable, for It will encourage those responsible for the broadcast ing programmes to make greater efforts to do things never before attempted. PULLMAN, Wash., Dec. 16. Pos sibility of using the new 600-watt broadcasting radio station now be ing installed at Washington State college, to aid the extension de partment in ita work, is being con sidered by the college authorities. Should the college authorities de cide to use the station for this pur pose it would be possible for the college to offer complete courses in such subjects as sociology, myiua ing assignments and lectures, to any one having a receiving set within 1500 miles of Pullman. Twn committees have been ap pointed to arrange1 programmes In cluding musical numbers, lectures, general information and special work, which will be sent out by the different departments of the college. The Palace Hip theater, lin Seat tle, Wash., holds out a novel induce ment to the artist 'n the way of a radiophone in each dressing room. Here the artist can sit while making up, or between shows, says' "'Vaude ville News," and hear lectures, Ber mons, music, etc. Its effects are marvelous, for the artist keeps out of the wings, be'ng interested in the radio, and happily forgets that evil tendency of "talking shop." This seems to be a new blessing to the theatrical world. Joseph iviul ler, manager, and the stage hands do all in their power to bring hap- p'ness to the artists while playing in Seattle, according to Mr. Em mett. Lead-in wires for a transmitter should have a capacity equal to that of the aerial. When the lead-in has a smaller capacity it offers im pedance to the high frequency oscil lations and the radiation is accord ingly reduced. The lead-in should be as short and direct as possible, as it is not intended to radiate en ergy but to conduct it to the aerial. E. L. KNIGHT & CO. 449 Wahlnson St., Near 12th Broadway 0145. SPIDER WEB FORMS - 20c A XMAS SUGGESTIONS RADIOPHONE Radio Sets and Parts. "KHieHT MAKES DAT THE ELECTRIC WAT" RADIO SETS of all kinds, made to your order. Complete sets in stock. Large supply of parts. SMITH-McCOY ELECTRIC CO. 264 Alder St. Main 8011 RADIO A completely equipped sendlna- and receiving station and experimental laboratories. - Graduates are qualified to pass any government examination. Day and nlirht classes. OREGON IKSTITFTE OF TECHNOLOGY. 4th Floor Y, M. C. A. Sixth and larlor. STATE SCHOOL FOR BLIND ENJOYING A POWER STATION. opera season is not easy, although I every one of the recent operas in r'nrt nnri wan ottPnridn hv nnnils from the state school. Concerts in the school here can . be held only occasionally. Since the installation ,of a fine radio set equipped with a magna vox in Jiie school auditorium, the students can "listen Jn' every night to the best in the musical world, la the month that the set has been in operation the auditorium has be come the most popular room in the whole sehool. Concerts which here- j toiore nave involved a teaious trip to Vancouver or Portland or the importation of artists from outsida cities are enjoyed with no more Please aend me the above hook-up. 2. What is meant by C. W. trans mission ? a. My antenna is 20 feet high at one end and .30 feet high on the other. Would I be able to hear any better or farther if I raised both ends to 40 feet 7 4. Will you send me the rules for volts, amperes, meters, millimeters, mil lihenries, etc. ? T. R., Portland, Or. 1. The operation of a receiving set is too lengthy a subject to be taken up in the limited space of this column. If you will send an ad dressed ana stamped envelope, will furnish you the hook-up and direc tions for operating the set. 2. C. W. is the abbreviated term for "continuous waves," such as are set "up by an oscillating vacuum tube. 3. Yes. If the antenna is raised higher on both ends the results will be better in reception of signals. 4. Would advise you to get a good book on' radio In which these rules are contained. All these rules for which you ask Will take up a good sized chapter in any radio book. Editor Radio Department: 1. Can I add one or two steps of am plification to a peanut set? It so, please send me a hook-up. 2. With this set and amplifier and an antenna 37 feet high and 125 feet long, how far ean 1 hear? 3. Could I hear still further if I added a variometer? . R. S., Portland, Or. 1. Tes. Send a stamped and ad dressed envelop and the hook-up will be supplied to you. . 3,. No definite distance can be guaranteed with any type of re ceiver, as the reception depends on many other things, such as the lo cality In which you live, the atmos pheric conditions, the proximity of power .wires, or type ground you use. However, under good condi tions such a set often will receive from as far as 1000 miles. 3. If the variometer is placed in the plate circuit of the detector, so that the circuit is made regenera RADIO QUERIES AND ANSWERS A CHRISTMAS GIFT One of the best CHRISTMAS gifts you could make to your family is a GOOD RADIO set. A RADIO set is something that -will be in use the year round and will give you more enjoyment than anything else you may get. We are selling our GUARANTEED sets for CASH or TERMS. The terms will put a set in your home for CHRISTMAS and you can pay for it during next year. These sets" are built by our EXPERTS, and are going very FAST so in order to have youra for CHRISTMAS you should place your order NOW. We will also REBUILD your set so that you will be able to-receive those OUT-OF-TOWN stations you have wanted to hear. You are missing some very interesting experiences if you are not hearing the OUT-OF-TOWN stations. Rad:oSery:ceBureau,Inc. 427 WASHINGTON ST. PORTLAND, OREGON (Telegram Corner) CONCERT BROADCAST effort than the walk from etudy rooms to the auditorium. "The machine is in- constant use every night from, the time broad casting begins until 10 o'clock,' Mrs. Herbert Chapman, wife of. the superintendent, an instructor at the school, declared. "The children drift In after their studying is done, and on nights when special concerts are being broadcasted we have no study hours and the whole school assembles in the auditorium. "The Oregonian concerts are won derfully fine and clear. It seems as if the performers were right in the room. We hear concerts fre quently from outside cities as wel.' tive, the reception range of the set will be greatly increased. Editor Radio Department: 1. Can spiderweb coils be tapped for sharper tuning? 2. How would a set of spiderweb coils be connected to a vacuum tube detector? 8. Why does radio work better In the night time than in the day time? A FAN, Ashland, Or. 1. They can be tapped but they are usually wound to cover a nar row band of wave lengths which is varied by changing the capacity of the accompanying condenser. For other bands of wave lengths, a set of larger coils are used, and so on. 2. A good hook-up for spiderweb coils was published in last Sunday's Oregonian. If you write to the cir culation department you can pro cure a copy of the issue. 3. It is due to the absorption of energy by the sun's rays and the fact that the upper limits of the atmosphere are more sharply de fined at night than in the day time. Because of this fact, the reflection of radio waves from; the upper limit which is about 60 miles from the earth, is greater at night than dur ing the day time." Editor Radio Department: 1. How do the different -minerals used in crystal detector range in sensi tiveness? - 2. Can a crystal deteetor be hooked j up to a phonograph cabinet so that more than one person can- hear the concerts at ' one time? 3. What is the beBt type of tuning unit for the crystal detector? I. P. K., Goldendale, Wash. 1. Galena is considered the most sensitive of any of the known min erals. Following galena come sili con, perlkon , (bornitezinclte), iron pyrites and carborundum. The last mineral usually requires a local battery. 2. Unless one or- two stages of amplification are used in addition to the crystal detector, it is not ad visable to hook the set to a phono graphic sound chambers. Without the amplification the signals won't be strong enough to be heard very far from the ears. 3. The loose coupler or vario- FROM THE OREGONIAN HIGH- Seattle, San Francisco and Salt Lake City. One night we picked uj a broadcasting station on the east ern coast, in New Jersey, I think." About 65 children from all parts of Washington are registered at the school this year. They range In age from little tots of 5 and 6 years of age to young women and youth! of high sAiool age. Only a small percentage of them are totally blind and most of them can" see enough light to find their way about. They are as happy as any other children, and for the very reason that one of their faculties is impaired they make better use of the others than the average person, coupler, preferably the first, will give highly efficient results when used with the crystal detector. Editor Radio Department: 1. What Is the. best hook-up for the 2. Which'side of the A battery should have the rheostat in it? s. How can I make a rood rrli) im tor a peanut tube set? 4. How ean you tell the grid, plate and filament connections of a vacuum '"be? 8. N., Woodburn, Or. 1. Any regenerative hook - up jsed with the standard type of tube can be likewise used with the pea nut tube. 2. The negative side of the fila ment is usually where the rheostat Is place. J. Take a small piece of hard rubber or bakelite and place two small binding posts about three eighths of an Inch apart. Between these binding posts scratch lead pencil marks until you get the grid leak of the proper size. This can only be found by experiment. 4. Use a. pair of phones and 6mall battery. You can easily find the filament connections through two prongs of the tube. By llehtiner the I filament you can Easily determine io De Forest Radio Receiver This is a tube type detector, which has a receiv ing range of approximately 150 milesWill bring in signals on wave lengths between 145 and 800 meters. By adding honeycomb coils this can be increased to 15,000 meters. The circuit used is one of the most efficient non regenerative hook-ups known, v Price We handle all Standard lines Radio Material ELECTRIC CO 75 6th St. Stubbs Bldg. the plate and grid by the flow of current' through the phones. It 'will give a loud click off the plate and a weak click off the grid. Editor Radio Department: 1. . How do you connect two mfds fixed condensers to make a .0003 total capacity of .001? 2. Will the two condensers give better results If usgl around the phones? 3. Which Is better, a variable con denser in the aerial circuit or one placed in parallel around the primary of the variocoupler? 4. How many turns are usual in the primary of a variocoupler? . - li .W., Portland, Or. 1. Connect the two condenses In series, that is, the end of one is con nected to the end of the other, while the two outside ends are placed around the phones. v' 2. This can only be determined by experiment With some phones more capacity Is needed than with others. However, the capacity of the phone condenser is not critical and almost any size will work well. 3. For short wave work the con denser should be - placed in the aerial circuit. For longer waves, around the primary coil. 4. Sixty turns is the usual num ber In the standard size coupler. Hints for Fans. What is good for commercial sta tions should be good for the begin ners and amateurs. A shield for the lead-in is used on ships to prevent rain from coming down through the deck insulator. You can profit by using this also, as It prevents rain from leaking through your impro vised lead-in insulator. It resembles a funnel, and. In fact, can be made from a large funnel such as used In .garages for pouring gasoline into machines. A good, strong cork Is placed In the small neck of the fun nel. Tne aerial lead-in is pushed through the cork. Sealing wax is then poured In the funnel to make a rood background for the cork. The funnel is then shellaced to resist rust. xN . Some lead-in insulators are mere ly porcelain tubes. These can be laid flat and brought through the opening Just above the window sill by raising the window two inches and placing a piece of wood be tween the window and the sill. The board should have a piece of weather stripping between it and the window. The holes for the in sulators should be bored on a down slant so that water will not run into the room, but will drop off outside. Aerial supports It is advisable to support the aerial by means of pul leys and ropes, so that it may be lowered for repairs. Good galvan ized pulleys and rope can be had at a low price, or flexible wire may be purchased at a reasonable figure. Wire is preferable to rope, as the latter shrinks In damp weather and stretches when dry. It rots very easily, too. Answer Galena is one of the best minerals to use as a crystal. How ever all galena is not blessed wltb sensitive stfots. Get a piece as large as possible and then if you do not ge the desired results when the OH.r' whisker is brought in light contact anjl after a careful search, break the" crystal Into pieces and try each piece again. Be careful always in handling a crystal' to keep grease and oil foreign matter from the face of it, as it is impos sible' to get results with a dirty crystal. Should you find that your I orystal j3 not, clean USt ab,U Chn ton and a few drops of carbon I tetrachloride to clean tne suriace. It is advisable to solder all joints, but when working on the aerial this Is not always practicable. Where It cannot be done a good substitute follows: First clean the wires to be spliced and join them by making a Western Union splice, then wrap several layers of tinfoil over the splice and last apply tape. Each step of amplification re Quires another tube. - Sound waves travel at the rate of 1100 feet a second. A radio set may act very differ ently on different days under differ ent conditions. Hang up the receivers when not In use. They will retain their sensi tivity longer than by being knocked about on the floor. Constant jars will reduce the effectiveness of the permanent magnets In the receivers Xmas '36 Operating Broadcasting Station KQY Tliis A SIMPLE ' RADIO-FREQUENCY HQOK-UP IS ILLUSTRATED Coil Consisting of From 40 to 60 Turns of No. 24 or No. 26 Enameled Wire Is Used. IV M'l - V V One mtrnge of radio frequency can be added to a detector irtthont nxe of transformer la tbls book-np. V Standard varlo-counler. X Sinele slide inductance coil of from 40 to 60 turns. ; C Eleven-plate vari able condenser. A SIMPLE radio-frequency hook up which will bring in the long distance stations is shown In the hook-up above. It requires a little more care in tuning, but un usual results have been obtained with it all over the country. Instead of the usual radio-frequency amplifying transformer, this hook-up uses a coll consisting of from 40 to 60 turns of No. 24 or No. 26 enameled wire wound on a three inch tube. This coil should be pro vided with a slider arrangement so that each turn can be cut in or out as desired. A single-slide tuning coil purchased in any of the chops will do nicely. A one-plate condenser 1b used in shunt to the coil, for fine adjust ment. A larger condenser can be used, but it should have a vernier attachment The two unite are con nected between the plate of the amplifier tube and the positive end of the "B" battery, as shown in the diagram. Other units necessary for this amplifier, to those who have only a detector set are the following: An amplifier tube, a 2214 volt "B" bat tery and a rheostat. The same A or six-volt storage battery can be used for also lighting the amplifier tube. Both "B" batteries are connected in series. First place the condenser (and the one In shunt to the coupling coil Radio fans will appreciate the lower prices found here on the ntnndard parts of radio equipment. We mention here a few typi cal examples of our low prices, reveal lnir to you the" opportunity of buying lor less. Our radio department will save you money. Marvel Crystal Receiving Set $ 1225 Complete set with head phones and antenna equipment, all ready to put up. This set will receive messages from a Rood size area and is a bier value at this low price. One Tube Set Complete with 80-hour battery, bulb, "B" battery, head phones, antenna equipment and single circuit, regenerative tuner. Same set with 2-stage fiJQQ amplifier vO7 liifi ANNOUNCEMENT ' THE SHIP OWNERS' RADIO SERVICE, ISC, have decided to quit retail trade. We are golnfr to sell out the stock of the Portland store, as this is the only retail store we are now operating. Every article In our store at a reduction of SO per cent and some reduced a great deal more. ABSOLUTELY NOTHING RESERVED! All mail orders must be accompanied by suf ficient postage. No C. O. D. shipments, no charge accounts, no exchanges or returns. This is . wonderful opportunity to MAKE IT A RADIO XMAS A FEW BARGAINS ARE LISTED BELOW PRICES - Regular. Sale. 9 Firco Receiver. Detector and two-stage am plifier; no cabinet $ 70.00 828.00 S Profco Beceiver, Detector and two-stage Amplifier; nice cabinet J110.00 855.00 E Clapp-Eastham He6enerat've Receiver; nice cabinet $ 40.00 830.00 4 Superphone long and short wave Receiver, Detector ana two-stage Amplifier .110.00 $55. OO 1 Magnavox two-stage power Amplifier 80.00 348.00 3 Westinghouse Receiver, Detector and two stage. (This is one of the best receivers made for long distance) J132.50 892.75 Fesco Knobs and Dials. 3-inch, -inch hole... SOc 30C Electrose Knobs and Dials, 3-inch, -inch hole.f 1.00 40d Firco Sockets, bakelite base, nickel plate shell. 90c. 25 Firco Sockets, bakelite base, nickel double shell. 1.75 5()o Firco Sockets, bakelite base, nickel triple shell. 2.75 75c Radio Service Sockets, bakelite base, single... 1.00 20c If you have our catalogue you can discount any article listed 0 per cent and send money order accordingly. We will keep open on Saturday evenings until 8:30 until after the holidays. THE The Oldest Exclusive Radio Store in Portland. ( Mail Order Service 310 OAK STREET PORTLAND, OR. DfTjjcrod -4 i f 1 4 ' i.f - i - i.i ft a'. VOLTS B 3 voi r s should be the only one in the cir cuit) at zero. Then, adjust the vario coupler until the desired signal is heard, after which, varying the con denser will somethimes but not al ways increase the strength of the incoming signal. Incidentally, In creasing or .decreasing the filament brilliancy of the tubes, independent ly, by means of their respective rheostats will oftimes bring in the stations sometimes as much as 25 per cent stronger. The reader is warned that while th sensitivity of a circuit of this kind is greater than most audio frequency sets, more patience is also tequired to "get" the desired sta tions. . It will also be found that the strength of signals which are al ready loud and distinct will hardly be affected, but It is the weak and distant signals which are brought in strong and clear by the added stage. Body capacity is a term used to describe the effects of bringing the hand close to the radio set and in most homemade sets causes consid erable annoyance by fading signals. This can be overcome by coating the back of your panel with shellac, and before it dries putting on small sheets of tin foil, being careful that the foil aoes not toucn any of the working parts or wires. The foil should be connected to the ground terminal. Head Sets 2600 Ohm Crystal Sets, as low QJ JQ Baldwin Phones, type 75 Bakelite Dials, ...24c, 69c, 79c Amplifying formers ... Trans- $2.70 :'B" Batteries, 22- d 1 JA volt, tapped ., Ol.OU Mounted Crystal Detec- QQ- tors, each OIC Potentiometers, 10 0 1 in ohms iDl.lt' Standard size Plugs, on each JC Two-slide Tuners, $1.95 $4.45 each Tuska Bakelite Va riometers Dubllier Lamp Sock $1.29 et Antenna . . ISO Degree Variocouplers $1.75 We carry a full line of Stand ard Apparatus and Equipment. HC Store 3. B. WEED, Mgr.