File:Radio for everybody; being a popular guide to practical radio-phone reception and transmission and to the dot-and-dash reception and transmission of the radio telegraph, for the layman who wants to (14755522634).jpg

Identifier: radioforeverybod00lesc (find matches)
Title: Radio for everybody; being a popular guide to practical radio-phone reception and transmission and to the dot-and-dash reception and transmission of the radio telegraph, for the layman who wants to apply radio for his pleasure and profit without going into the special theories and the intricacies of the art
Year: 1922 (1920s)
Authors: Lescarboura, Austin C. (Austin Celestin), 1891-
Subjects: Radio
Publisher: New York, Scientific American publishing company (etc.)
Contributing Library: Boston College Libraries
Digitizing Sponsor: Boston Library Consortium Member Libraries

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one lines, trolley cars, elevators and otherelectrical appliances and machinery, the detector shouldrespond to the electromagnetic waves given off by elec-trical machinery of all kinds within range. In otherwords, if the detector remains absolutely silent, then it isevident that no sensitive spot has been found; but if itcauses clicks, scratchy sounds, buzzes and other noises to RADIO FOR EVERYBODY 145 be heard in the telephone receiver, then it may be takenfor granted that the detector is satisfactorily adjusted.Sometimes the sensitiveness may be tested by turning onand off a nearby electric lamp. This should produce aloud click in the telephone receiver. However, if a humis heard, this should not be considered as an indication ofthe sensitiveness of the detector adjustment. Indeed, the hum is caused by what isknown as induction, given offby an alternating current line.This hum may be picked upwhen the point or wire is noteven pressing on the crystal;so that, far from indicating a e\
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A combination receiving and CW transmitting set of the inter-panel type, with the various units standardized so that they can be assembled to form any desired arrangement for the amateur station. sensitive detector, it should indicate that the detectormembers are not even in proper contact. For those desirous of making sure of their crystaldetector adjustment, it is perhaps best to use what isknowa as the buzzer test. This calls for a small buzzer,such as is used in bell circuits. The buzzer is connectedin the usual manner with a push button and cell of drybattery, but a wire is brought from one side of the buzzerinterrupter to the ground lead of the receiving set to betested. Then, when the buzzer is operated, the electro- 146 RADIO FOR EVERYBODY magnetic waves given off by the buzzer interrupter areimpressed on the radio receiving set and the detector canbe adjusted for sensitiveness in the same manner asthough the operator were Hstening for a radio transmitter.The buzzer test is st

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