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Modern Progress in Telephony
General Characteristics.

Siemen's Neophone.

The Neophone is an instrument of the microtelephone type in which all the disadvantages of previous varieties of that type have been overcome. It is adapted for both automatic and, by the substitution of a dial dummy for the dial, for manual exchanges. Normally it is arranged as a table set, either with a combined or separately mounted bell-box, and it is as a table set that it is described in this article. It is also made in several forms suitable for use as wall sets, of which particulars will be supplied upon request. The form arranged for use with a separate bell-box can be employed with existing bell sets of the normal C.B. type without alteration in apparatus or wiring. In construction, materials, and finish it is insensitive to temperature changes and humidity and is suitable for widely varying climatic conditions. It is easily installed, durable and reliable in service, and all parts are simply and easily replaceable in maintenance or repair.

No one needs to be convinced of the superior convenience of the microtelephone over the fixed transmitter type of instrument. The Neophone can be used with ease among drawings, papers, books, etc., without disturbing them; it leaves one hand free for turning over pages or making notes and it does not restrict the bodily position of the user in any way. Yet it is superior in transmission efficiency to the fixed transmitter instrument, even allowing that with the latter the speaker is expected to bring his lips close up to the mouthpiece; it maintains uniform resistance and transmission efficiency no matter in which position the telephone is held; howling and frying, so often experienced with microtelephones, are not possible even on the shortest lines; breaking circuit, sparking and burning of the electrode faces of the transmitter are entirely eliminated. In addition, articulation is greatly improved, while side tone and the effects of local noise on reception are very much reduced, so that in use under ordinary conditions, the practical improvement in efficiency is very much greater than that shown by measurements of transmission volume made in the laboratory.

(Concluded.)

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