. The Street railway journal . atus in the talking and signalling circuit isthoroughly insulated and well protected from injury. Oneof the special features is a one-half micro-farad condenserin the receiver circuit, to eliminate a switch hook on the box,for the purpose of breaking the line circuit. With thisarrangement the instrument may be rung any time when onthe line. The ringer is not across the line when ringingout. The generator shunt cuts out the bell, putting the fullvoltage of the generator on the line when ringing with thegenerator, thus giving the greatest power. The all-metal combi
. The Street railway journal . atus in the talking and signalling circuit isthoroughly insulated and well protected from injury. Oneof the special features is a one-half micro-farad condenserin the receiver circuit, to eliminate a switch hook on the box,for the purpose of breaking the line circuit. With thisarrangement the instrument may be rung any time when onthe line. The ringer is not across the line when ringingout. The generator shunt cuts out the bell, putting the fullvoltage of the generator on the line when ringing with thegenerator, thus giving the greatest power. The all-metal combination telephone shown in the viewof the open set embodies many features which make it anespecially good instrument for use as a linemans testingtelephone. Like the complete telephone cabinet, it is de-signed to withstand rough handling, and the manufacturersclaim that it has no parts which are perishable. The frameis made of seamless brass tubing especially drawn. Theregular solid back transmitter electrodes are enclosed in a. GENERAL VIEW OP TESTING SETcase consisting of three pieces mounted directly on theframe by large screws. Perforated cast-brass mouthpieceand clamping ring hold the diaphragm and diaphragm springin place. The receiver is the regular operators type in a speciallydesigned case, having all exterior sides and edges made ofmetal in order to prevent breaking the ear cap, which isenclosed as much as is practicable. The microphone isprovided with a battery push button that cuts in the batterywhen necessary or only when talking. This button alsoprevents the annoyance of side tones taken up by the trans-mitter when listening in on the line in a noisy place. Bothtransmitter j(nd receiver interior parts are accessible by un-screwing the clamping rings. This form of complete test-ing telephone, known as No. 841 3-bar, No. 842 4-bar andNo. 843 5-bar generator call linemens test set, has been given a severe test by some of the leading high-tensionpower companies operati
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Keywords: ., bookcentury1800, bookdecade1880, booksubjectstreetr, bookyear1884
