Radio broadcast .. (1922-30)

, HAT Our Readers Write Us A Word from an Enemy — of the Single Circuit IT IS growing more and more plain that the enemies of the single-circuit receiver are legion and are increasing in numbers and in intensity of their opposition. As has often been remarked about the unfortunate widespread use of the single circuit set, abolishing it is so largely a matter of militant public opinion that results come a bit slowly. RADIO BROADCAST has in the last two years, lost some "friends" by its constant advocacy of the abolishing of the radiating receiver, chiefly among advertisers, be it said. It is interesting to note that now, very very few single-circuit receivers are marketed by manufacturers who make even faint claims to be reputable. Editor, RADIO BROADCAST Doubleday, Page & Company, Garden City, L. I. DEAR SIR. I wish to compliment Mr. Willis K. Wing on his excellent summing up of "The Case Against the Radiating Receiver," but if it is in order, I would suggest a final point with which he might have rounded out his remarks on the single-circuit receiver. Even if it were not for its severe radiation, the single-circuit set is not even selective enough to merit its consideration as a broadcast receiver. The recent Department of Commerce ruling calling for a compulsory quiet hour from 7 to 10.30 p. M. on the part of amateur stations was necessitated by the fact that at that time the single-circuit was the commonest type of receiver in use. This was not on account of the fact that amateur continuous wave stations actually created interference themselves, but simply because the single-circuit users were not able to tune the near-by stations out, which is, in a sense, unfair to the amateur. This affliction of broad tuning which also gives the same trouble when the receiver is in a few miles of a broadcasting station, is caused by the fact that when resistance is included in an oscillatory (tuning) circuit, the tuning of that circuit is made broad. In the single-circuit tuner, the coil, condenser, and antenna are all connected together as to form one circuit, hence the name. Unfortunately, however, antennas have resistance, and most of those built for broadcast reception have comparatively high resistance, so that the antenna being included in the circuit through which the signals enter the detector causes the tuning to become broad. When the tuner is set for a broadcasting station, any other transmitter being operated in the neighborhood on almost any other wavelength will be heard, probably all over the dial. The remedy for this is to "loose couple" the set; in other words, to bring the antenna and ground leads to a separate coil to be coupled to the grid tuning coil. The honeycomb coil tuner is the outstanding representative of this method of construction, and the so-called three-circuit regenerator as well. H. S. G., Kitchener, Ontario. A Radio Samaritan TT IS most interesting to notice how the 1 gospel is reaching all through the country and how the feeling against the squealing or radiating receiver has taken practical form. People, wherever possible, are getting to do something about this unfortunate situation rather than merely holding forth at great wordy length. Editor, RADIO BROADCAST Doubleday, Page & Company, Garden City, L. I. DEAR SIR. Since reading your article "The Case Against the Radiating Receiver" in the October RADIO BROADCAST, I came across this notice in our local paper. B. N., Gloucester, Massachusetts. RADIO CONDITIONS IN G1OUCESTEB LAST NIGHT Conditions were good last night. Most stations came through strong. There was very little fading and static. — R. P. M. WARNING If the person in the vicinity of Center Street who tunes in morning, noon and night and never gets the station clear'without squealing, will please call at my shop, 101 Main St., with his or her radio set. I will make the necessary adjustments and changes in the set free of charge, so that above party will enjoy his radio more, and others in this neighborhood may enjoy theirs also. R. P. MERCHANT.