WIRELESS NOTES.

Shannon News, 10 September 1926, Page 4

WIRELESS NOTES.

(By "Q.R.M."). The Tasmanian broadcasting station, 7ZL, is nearly ready to give regular transmissions on the high power of 3000 watts output. Special three-kilo-watt transmitting valves of a type never befo:e used in Australia will be employed in the transmitting appartus. These valves are known as .':e s'lica type, and are cooled by a blast of air in preference to the more usual cvstein of water-cooling used with these large valves. ' ' " Seeing Avhere a tireless message is coming from has been made possible by a brilliant invention of the radio research station < at Slough, in England. The method employed is as follows: Two frame aerials are mounted at right angles to each ether, and the incoming signals, operate a cethode ray beam which causes a blight spot to appear on a fluorescent screen. This spot immediately swings to a position on the screen, showing the direction from which the signals are coming. The advantage of this invention co aircraft and' shipping would be enormous. The frame aerials are fitted into the wings of the aeroplane, the pilot thus being able to find his position before alighting at an aerodrome. Australian backbloeks are quickly taking advantage of the church ser- ; vices broadcasted from the various Australian cities. In many places where a minister can hold a service onlv once a month, or even in two months, four, and live-valve receivingsets are being installed and the, services picked up and delivered hy means of a loud speaker. The collection is" taken up to the strains of a "city organ hundreds of miles away. Peopl" who have been present at Just such a one of these "wireless" services state that the whole service is even as impressive as-when the minister is there in person. The people sing the hymns to the accompaniment of a giCi't choir anil organ away across the miles of Australian desert. Mr. A. W. McDonald, of Sunny Corner, which is nearly 130 miles. from Sydney, states that he can pick up 2F.C. on his crystal set at any time of the day or night. Mr. McKcen, of Wellington, recently asked the. Postmaster-Geneva! (Hon. Mr. Noswortky) whether all public hospitals and benevolent institutions could be' exempt from paving license fees. The Minister replied: "The P. and T. Department is bound to see that a license is taken out and a fee paid by every owner of a receiving set owned by a listener. In the circumstances,! it is regretted that no exemption from the payment of license fees can be granted!" Aussie Programmes for New Zealand. A great deal of interest is being taken by listeners-in in the decision of the Australian officials in regard to providing a service for New Zealand through commencing the evening broadcasting two hours earlier. The Sydney Sun places the position thus: "New Zealanders are not well catered for by their own country jn the matter of broadcasting programmes. Should Australia help them even though they pav no license fees for the services? The popular pastime among listeners-in in the Dominion is tuning in to Australian and, particularly Sydney stations. It has been suggested that Australian stations should provide special programmes . one night a week for the benefit of New Zealanders, and that these should be put on early, to compensate for the faict that New Zealand'

is an Lour and a-half ahead of Sydney time." Mr. Maclardy, managing director of 2BL, said that there could be no objection to arranging a "New Zealand t Night," as many artists at 2BL came from New Zealand. But the idea of a special time did not appeal to' Mr. Maclardy. He said that the object of his station was to provide a service for listeners-in in New South Wales, and a dislocation of the programmewould interfere with the popular bedtime stories.' ■.' " ' , Mr. George Wright, a director of 2FC, says: "We cannot increase the cost of our programme simply to please New Zca!and. The first consideration for stations in this State is to give New South Wales a first-class service. The Melbourne station, 3LO, is prepared to put on a speeial programme for the Dominion. Mr. H. P. Brown, Director of Postal Services, states that the attitude of his" department was one of encouragement of any broadcasting that would help to strengthen the bonds of Empire. He could not see why several items of Empire interest should not with advantage be included in the programme, providing Australian interests were safe- „ guarded. Radio Photography. That the invention of radio photography is rapidly nearing perfection is .being, demonstrated very clearly by Radio House, London. Although the system in itself is not new, the ideas involved dating back to the middle of last century, the modern apparatus is improved upon to such an extent that a commercial service is certain. ■ L The first message was sent to General Dawes, \ Vice-president of the United States, and stated: "Greetings in the second picture radiogram ever.< sent across the Atlantic or any other ocean. The most interesting test was the transmission of a cheque. This w r as a checpie drawn upon the Bankers' Trust Company in New York by General Harbord in favour of the Radio Corporation of America. The cheque w r as endorsed and duly honoured in less than an hour after it was presented for transmission in London. The apparatus is stated to "cluck like a hen," due to the fact that the received pictures are nothing more or less than a series of dots and dashes, depending on the degress of light and shade of the picture that is being transmitted. As the writer has already given a somewhat detailed account of the method employed in the actual sending and receiving of a picture in a recent issue of these notes, it will not be gone into again here, except to state that, when a white portion of the picture is being received, no marks arc made upon the paper, and when a 'grey or dark portion is being transmitted, the dots and dashes are either lighter or darker in type, and spaced closer or more widely apart. Many of the dots are so small that they appear as one whole patch unless closely inspected. This will be more clearly un-,. dcrstood when we realise that it is possible to receive 5760 dots t*> the square inch. When a picture is being transmitted by means of wireless the wireless waves are liable to be affected by "static" and "fading," static causing extra dots and dashes and fading a weak pieture. -