Radio today (Jan-Mar 1939)

O wide awake radio dealers, Clarion Institute of Sound Engineers offers ■ the greatest opportunity, to profit on sound sales, in the history of the industry. The C.I.S.E. Plan crushes every bone of contention the P.A. equipment dealer ever had! Closes the profit leaking gaps! Sets the dealer up on a really competitive basis ! C.I.S.E. can bring new "sounrf" profits to you. We want you to join this Big Parade to "sound" profits under the C.I.S.E. banner. Membership in the C.I.S.E. costs nothing. Get more details! Now while you are reading this ad, clip coupon and send for a FREE invitation to a merchandising plan that assures profits. CLARION INSTITUTE OF SOUND ENGINEERS 69 WOOSTER STREET, NEW YORK CITY' j CLARION INSTITUTE of SOUND ENGINEERS , 69 WOOSTER ST. NEW YORK. N.Y. RT339 I Please send a C.I.S.E. application imI mediately. This, in no way obligates , me of course. | Name ' Address City State Smite Hetes Aeroscope antenna Loop antennae were used on some of the first broadcast receivers, but as the first antennae of this type were large and cumbersome and would not fit into the cabinets, their advantage was offset by the inconvenience they presented. To eliminate the troublesome antenna wire and to make the small sets as nearly portable as possible the engineers have developed small shielded loops which also effect a distinct reduction in local static disturbances, and an increase in selectivity. There are three factors that effect the signal pickup of the loops, according to Admiral's engineers. 1. The physical dimension. The mean dimension must be as large as possible for the best signal pickup; also the loop must be sturdily constructed in order not to disturb the alignment of the set. 2. Q of the loop. The coil must also have good electrical qualities known as Q. The higher the Q. the better the selectivity. 3. Effect of metal chassis. To eliminate the effect of the close proximity of the chassis, a plate of non-magnetic material is placed between the loop and the chassis. This also serves as one side of an electro static shield. Noise reduction is obtained in two ways, by the directional properties of the Aeroscope, and the use of the electrostatic shield. By placing the set so that the noise source is at right angles to the flat surface of the loop, or zero response, a large increase in signal to noise ratio is obtained. The shield prevents electrostatic charges from making a cir cuit through the antenna to ground by shunting them into the ground directly, at the same time allowing magnetic waves to reach the loop. In remote sections where the pickup on the loop would not be adequate for reception of distant stations, an outside antenna may be used, as the Aeroscope provides for its use. A very good antenna is necessary in order to show any improvement in signal pick up of an electrostatically-shielded loop. Round-table discussion Rubbing shoulders with radio servicemen from coast to coast . . . frequently addressing gatherings here and there . . . always ready to listen to the problems of servicemen and to advise them — Charley Golenpaul of Aerovox picks up a lot of questions in the course of a month, some of which are answered below: Q. Why do set manufacturers designate their component parte by their own part numbers? Why don't they state the characteristics? A. The answer to this question is quite obvious. Set manufacturers identify their parts by special parts numbers in order to compel servicemen to go to their own set distributors for necessary replacement parts. Otherwise the serviceman would go to any parts jobber and secure any standard type condenser of about those characteristics, to use as a replacement. From the set owner's standpoint, this exact-duplicate policy of set manufacturers as well as certain condenser manufacturers, assures a replacement which will restore the set to its original new condition. This is the purpose of special type numbers. SUPER RADIO SERVICE NEW LOW RATES Tubes Tested Free SO ■ All Parts Needed Carried in Stock EVERY JOB GUARANTEED ON ANY MAKE QUICKER SERVICE COMPLETE NEW EQUIPMENT PHONE 1266 INSTANT SERVICE These Art the Merits Upon Which We Invite Patronage: I. We employ berjest, well experienced ta&nfei»U 2. We buy wily trie very best materia)* and equipment. , £ Wk do not tolerate afiisrtprWentmil (statements or charges to onr i. If we make s mistake W£ MAKE IT GOOD r*ffir<}l*B*, 5, We cbar*« HONESTLY for what services we perform. 6. We juaraptee all work-, 'and that no parts are y»*d urtleM needed. •'OLDEST, LARGEST AND BEST EQUIPPED SHOP IN AUGUSTA" AUGUSTA RADIO COMPANY 316 NINTH STREET TELETHON ROBT. W". WILSON, Owner In medium-sized cities, newspaper advertising brings good returns according to Bob Wilson, whose advertisement is shown above. 84 RADIO TODAY