WIRELESS TELEGRAPHY IN AUCKLAND

New Zealand Tablet, 28 July 1910, Page 1197

WIRELESS TELEGRAPHY IN AUCKLAND

A TALENTED MECHANIC Monsieur Roussel, a middle-aged Frenchman, who is employed as carpenter and general handy man at the Sacred Heart College, Ponsonby, has developed a taste for revelling in the mysteries of electricity that amounts almost to genius (says the Auckland Star). In spare moments he has put his industry and talent to good purpose, and quite recently completed and installed a wireless telegraphic plant, practically making everything on the premises and effecting an improvement on the Marconi mechanism in one important particular. The ingenious Frenchman has himself made the battery; the Rhunkorff coil, in which seven miles of delicately thin wire has been absorbed; the spark gap; two condensers which are used to regulate the strength of the sparks; the transformer for treating the current in its passage from the spark gap to the aerial wire; the receiving apparatus; the timing apparatus, and the mast, with aerial wires, which has yet to be erected. The battery that has been made does not develop sufficient current to transmit messages to a greater distance than 40 or 50 miles. A six-inch spark only can be obtained, and it requires a four or five feet spark to allow the wave travelling a distance of 500 or 600 miles. But the apparatus is admirably adapted for the educational purposes for which it has been designed, and the practical demonstrations that can be given to the college students is more effective and interesting than explanations and theoretical illustrations.

With the exception of the battery, which affects the transmission of messages in the manner _ stated, the plant can deal quite effectually with the reception of messages at almost any distance, and this fact has been demonstrated in an unexpected manner. Through legislation prohibiting the erection of the poles necessary to carry aerial wires to receive waves the receiving apparatus at present is unconnected, but so sensitive is the magnetic coherer that warships’ messages have been intercepted, one especially (though in code) being distinctly recorded, and another, presumably from a much longer distance, being rather faintly recorded. It is in connection with the receiving apparatus that Monsieur Roussel has made an important departure from the Marconi instrument. With the latter the coherer takes the form of a vacuum tube, with the air exhausted and filled with nickel and silver filings. The local production is a magnetic coherer, with an iron bar running through a glass tube, no air exhausted and the filling consisting of soft iron filings. Not only has the iron filings a better action, but the magnet adjusted to the side can be shifted to any position to increase or decrease the sensitiveness of the, receiver. This appliance is so sensitive that it records the slightest electric spark in the same room, and sparks from a Wimshurst influencing machine, located in another room some distance away, were also plainly and separately recorded. > It is also of interest to mention that the Wimshurst machine was made by Monsieur Roussel, and is valued at £2O at least. The whole of the wireless plant is beautifully finished, the brass work being particularly well fitted, and reflects the utmost credit on the industrious and ingenius Roussel, who is not only very unassuming, but most happy to offer explanations, as he did to a Star reporter, who inspected the plant. There is one matter that needs attention before the full benefit of the plant can he obtained. Legislation prescribes a penalty of £SOO for erecting apparatus for receiving or transmitting wireless messages, and the college authorities cannot without permission erect the mast for the necessary aerial wires. As the plant is intended only for educational purposes to transmit and receive messages from short distances, and not for the purpose of making a business of it, the authorities are hopeful that it will not be.. long before the required permission of the Government will, be given.'