ON THE AIR.

Hawera Star, Volume XLVI, 10 December 1926, Page 9

ON THE AIR.

RADIO' MESSAGE ™^™ v 45,00 l) MIDI’S TO DESTINATION. An outstanding example of the amazing strides that the radio amateur has made in the last tew years is furnished by the record ot a message that originated in the. Hawaiian Islands for delivery m China. Ai- . though ordinarily .such messages aie sent either direct to the destination, or by means of one or two intermediate relays, the communication in question travelled a distance of nearly circumference of the earth befoi reached the party for whom it was intended. flic message was started from amateur station 6DRL, at Honolulu, and from there 10 2NZ. E. S. Strout. jr., of New York City, no direct communication 10 China being possible. 2NZ gave it a fresh start towards t-lie Orient by passing; it- along to 9Zf. Don Wallace, in Minneapolis; but the latter evidently deciding that it would be better to- go back n little and get a running start, parsed it to the C.S. Navv’s Experimental Station, Mvll. ax Bellevue, near Washington, D.C. From Bellevue it was sent over to New Zealand, where 2AC. again unable to connect with China, handed it to a French station. The Frenchman evidently still had faith in the southern route, for he passed it along to a South Africa amateur. The South African happened to hear .a Phulippine amateur, so gave it to- him and the Philippine amateur delivered it to- an amateur in China who saw that the message reached its ultimate destination. Casual though this incident is, the average radio public; will probably be startled to realise the way the amateur of to-clay tosses messages back and forth between the different continents of the earth. Where five years ago it was considered a noteworthy achievement for an amateur to be able to transmit over a distance of 1,00(1 miles, the amateur of 1926 finds the world no larger than one of our smallest- States. WIRELESS v. GRAMOPHONE. Recently we came across a statement from an interested party, making comparisons between the gramophone and wireless, with derogatory references to one of them. The assumption was that these inventions were rivals. As a matter of fact they are not. Each has its own functions and, its own merits. Wireless extends the auditorium in space, the gramophone extends it in time.

The truth is that each of these inventions owes a good- deal to the oljher, and the true relationship is being appreciated as time goes on. From a technical point of view the gerat merit of wireless is its use of electrical methods of sound recording and reproduction. Another way of saying the same thing is that in wireless we have replaced slow-moving mechanical contrivances by harnessing up the lightning-quick electron. Quite naturally the possibility of applying similar principles to gramophone reproduction has been considered. It is quite safe to say that before very long gramophones and wireless receivers will be constructed 1 and operated _on very similar principles; in fact, it is' likely that the same machine may serve both purnoses. Electrical methods are already being used for the production and "reproduction of records, and electrical phonographs with various trade names are on the market. It is claimed that these machines produce, more faithful records, and that the reproduction is not only more equitonal but also under much more effective control. A record may he reproduced in a, whisper or with sufficient volume to entertain a city. ORIGIN OF THE MORSE CODE. With the development of radio telephone and broadcasting the number of listeners who can read “spark" signals is gradually becoming smaller. It must not be forgotten, however, that it is the Morse code of dots and dashes which enables about 97 per cent, of wireless traffic to be handled commercially. Until Samuel Morse devised his system of signalling with the aid of a combination of two sounds, varying in duration, telegraphy was carried on by means of a five-needle instrument, an old model o-f which is to be found in the Science Museum at South'Kensington, London. This method was superseded by the single needle telegraph, ia which the needle was deflected to one side for a dot and the other direction for a dash. From this was evolved the “sounder," still used in the post office to-day, and the “buzzer,” which came into prominence during the war in connection with field telegraphs. The Morse code is now international, being recognised by all countries, and :s the only code used in tho transmission of wireless messages. Ebonite can lie- repaired if broken, but the task is beyond the province of the average man, as a vulcaniser is necessary. When finishing the edges of a cut sheet, .first use a wood file, which lias a coarser surface than a metal file. Then a, nice smooth edge can be secured by scraping with long, steady strokes with a sharp pocket knife.' The blade of the knife must be at right angles to the surface of the ebonite otherwise it will catch and cut in. If a hole is drilled in the wrong place in a panel, it can be filled with some of the pitch-like material off the top of an old car battery, and smoothed over with a hot poker. It will be necessary to first soften the pitch and force it in or it can be nl@lted in a small ladle and poured in to the hole, which must be covered at the back with a email piece of wood.