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Show Radio Reception Goal Is Reached Not More Than 20 Per Cent of Sets Will Reproduce Repro-duce Properly. By KNUTE PETERSEN. In Radio World. Great iinpruveiiitnt lias been effected ef-fected in broartc-asting and reception during the past few years. In the early days even the liest transmitting stations used phonographs and player pianos promiscuously before the microphone. mi-crophone. Now these stations are using the highest type of available artistic talent directly before the microphone. mi-crophone. All "mechanical performers" perform-ers" are prohibited At first little thought was given to the modulation, often it happened that the wave was badly overmodu-latetl. overmodu-latetl. Now the average percentage of modulation occurs on even the loudest loud-est passages. Furthermore, the modulation modu-lation is so low that the second harmonic har-monic which Is introduced Into the signal when the percentage of modulation modu-lation Is too high Is negligible. Not much thought was given previously previ-ously to quality of modulation over the entire audible scale. Xow the modulation is the same for all essential essen-tial frequencies within a very close margin. At the receiving end the improvement improve-ment In quality has been slower than at the transmitting end, because many entered the receiver manufacturing field who had no adequate knowledge of the fundamental principles of radio in general and quality in particular. Accumulation of Knowledge. But knowledge of these things was accumulated and broadcast in technical tech-nical circles and great improvement in the received programs was the result. There was no one thing that came first in this general improvement of equipment. The realization that more power was required to operate loudspeakers loud-speakers satisfactorily brought larger tubes. The demand for the low notes in the signal brought large transformers transform-ers with high inductance primaries and it also brought resistance coupled receivers with high mu tubes. The demand for the low as well as the high notes brousrht cone speakers of large dimensions. The demand for convenience of operation op-eration brought about simplified control con-trol in the receivers. At first it was thought necessary to have a variable for every component part of the circuit. cir-cuit. As a result there were receivers which had a rheostat for every tube, I one or more variable high resistances for oscillation control, one separately controlled condenser to every tuned circuit together with a vernier condenser con-denser for each, potentiometers for varying the grid bias, taps on the primaries to change the coupling, taps on the secondaries for varying the tuning range, rotatable primaries for changing the coupling, and other variables var-iables without number. "Variomania" Disappears. As a result of this mania for variables, var-iables, which has been called "variomania," "vario-mania," receivers horrible in appearance appear-ance and well-nigh impossible to operate op-erate appeared. At present variables are used only for tuning aud for volume vol-ume control, and these are reduced to the smallest possible number. One or two controls for tuning and one for volume control are now popular. Many sets use a single control for tuning and another for volume control. con-trol. The result is that the receiver is simple to operate. The demand for convenience also brought socket power devices. At first these were designed to eliminate the "IV batteries only. Then they wore built to include the "C" battery also. Finally attempts were made to build them so as to eliminate the filament battery also. Fair results have been obtained and tiie prospects for complete success along this line are very bright. In fact, many receivers re-ceivers of excellent performance characteristics char-acteristics are now in operation in which no batteries whatsoever are used. Competition Fruitful. The ke.n competition between the phnnnrraph and the radio was one of the L-reatest forces for improving the qun'ity of both. Rut a few years ago the quality of phonographically repro-duf'd repro-duf'd music ''as atrocious. It was an ord.-al ;o listen to one of the in-stnrr.t'hts. in-stnrr.t'hts. Il.ijio came along. It was an inn't-'ivement over the phonograph, bad ih.rttsh it was at first. The ph(ti!"L'r;-ph manufacturers trot hiwy and M-'-hrd our insr-'mienis mp:.!,:,. of reprodil' in n ;'nr,:.:Me p:;;sio. T!-;lt was a ch:'Ht'iiL-e to tl;e r.-idi" oli-nio;:!. Tb.-v .!:..) it ::n.I now il.i- ::! is being f. 'ight. The best phonograph reprodih: ion is now on a par with the best radio reproduction, and either is almost as good as original. In the competition between the phonograph and the radio the phonograph phono-graph had the early advantage of greater talent. Nearly all the great artists of voice and instrument were bound by contract to the phonograph makers. Radio had to take what was left. At first there was not much to take, but now practically all the great artists are available to the radio. Radio has one advantage over the phonograph, and that is that its pro grams come to the listener right off the griddle. Phonograph music Is bought in the store deliberately at so much per package. Radio music comes wafting through space so that he who listens may hear by simply tuning in on it. A peach plucked off the tree is much more delicious than a peach fished out of a tin can. The two peaches might have grown on the same tree, or even the same branch ; but the canned peach grew a seaain or two ago, the one plucked off the tree did not stop growing more luscious lus-cious until the moment it was picked. The plucked peach ripened in the sun, the canned peach ripened in the shade of a warehouse, or perchance under the action of a chemical. So it Is with the music from the phonograph and the radio. The phonograph record rec-ord has been perfected in a studio and deprived of some of the human element. ele-ment. The radio rendition is the re-suit re-suit of growth and it is alive and vibrant. The artistic phase of radio has always al-ways outrun the technical development. develop-ment. In the early days when "mechanical "me-chanical performers" were used the technical equipment at both the transmitting trans-mitting and receiving ends was so poor that nothing but the novelty of the thing sustained interest in broadcasting. First-Class Artists Now. Later, when mediocre human talent was employed, the technical equipment equip-ment Improved a little but still the reproduced programs were mediocre. Now when artists of first magnitude perform before the microphone, the average reproduction is of first order. Of course one frequently hears a radio receiver which gives the illusion of reality, but such receivers are none too plentiful. The defect lies mainly with the receiving equipment. Soon the listener will not be satisfied with distorted radio. The general buyer is learning fast. Poor reception is not now so much a matter of technical development of receivers as with the exploitation of radio. It is well known how to build receivers capable of fidelity of reproduction, repro-duction, but tl ere are many sets built which cannot reproduce any program properly. And these sets are in daily use. They serve well to impart news and useful information to their owners, own-ers, but they are not able to create the illusion of reality. It is safe to say that more than 80 per cent of the sets in use today fall in this class. |