WIRELESS WORLD

Evening Post, Volume CXVIII, Issue 28, 2 August 1934, Page 21

WIRELESS WORLD

BY "GRIP BIAS' _ _ __

WIRELESS ROBOT

WILL CALL THE POLICE

NOVEL INVENTION

(From "Tho Post's" Representative.) SYDNEY, July 14.

An ingciuQtis, burglar alarm, based on the principles of wireless, has been invented by a Sydney musician. It is claimed that it. is necessary to have only 6nC of the instruments in any building, and- that it can be connected by wires that can be taken to, any room. A metal hand on a desk drawer, a ferrule on a carpet, «, metal baud let into a piece:, of - furnituro and linked by wiro with :thel: central :machinc would betray ■■ the presence., of. an intruder who approached within 12ft of them. They would mako no sound that the intruder could hear. Instead, using a special wave-length,, they would announce to the police, at police headquarters, the presence of the stranger. According to the inventor, a robber rifling an office safe or desk would proceed uninterruptedly with his work, but his proximity to tho concealed lead would operate the set, and a. metallic yoico would say into the loud speaker at Police Headquarters: "Police, police. Bobbers at such-and-such a number in so-and-so street." And it would keep on repeating the message until tho polico switched it off or the intruder moved out of range. The instrument is to have a special test before interested authorities, at-au early date.■■■ Th . inventor said he hit upon the alarm by accident when ho was trying to devise a now musical instrument.^ It was also accidental that tho machine proved to be a wireless receiver as well as a transmitter. And it was these facts that involved tho invention in red tape, and, incidentally, precipitated publicity which it was intended to withhold until the invention was ready for serious tests. A zealous wireless inspector • discovered that the inventor . was using the machine in the room of a city hotel for demonstration purposes, and hauled him before tho Central Summons Court on an information alleging that he had an unlicensed wireless set. He told tho Magistrate that it was a devico for, detecting crime. It was only after he had been using the machine for some time that ho found out that it would roceivo. messages'. However, he did not use it as a receiver. It had taken him three years to make. The Magistrate dismissed the anformation.

EADIO CONTROL IN FRANCE

An. interesting set of circumstances is influencing' the broadcasting situation in France at the present time, says "Wireless World" (London). It is only just recently that tho control of broadcasting stations in France has been taken over by the Government. Hitherto independent companies, for'the most part, havo been responsible for such'stations as have operated, and in most cases these have been maintained by revenue from advertisoments. ' " ~ "" '

There has boon little or. no co-opera-tion between individual stations, and little development has taken placo becuuse of..the.uncertainty as■ to what action tho Government might take.

This unsettled state of affairs has naturally had its effect upon the wireless industry in France so far as the receiving side is concerned. French firms have hesitated to sink capital into an industry which, was dependent upon programmes emanating from transmitting stations whose position as regards pormanency; was itself precarious.; It is probably . safe to say .that as many sots have been sold in France to date 'on the strength of programmes available from foreign stations as on the attractions, of the home transmitters. Although the potential market for sets is probably greater in France today than in any other country in Western Europe, there is no great French radio industry, and firms of foreign origin still supply a very large proportion of. the sets, although most of these sets are now built in France, because tho quota on imports makes it unprofitable to do otherwise. That the next two or three years will see an enormous boom in radio in France seems practically certain. France can no longer afford to watch the effect of broadcasting in influencing public opinion and meeting emergencies in other countries and ignore the similar advantages which an efficient broadcasting service would offer France. It must bo apparent to the French Government that France must be served through her area with an efficient coverage of broadcasting and that the programmes , must be of a character designed to' attract the masses, of .the population and ensure that listening-in will: become a national habit, for until that state,of affaire comes about the value of broadcasting as a national propaganda aid cannot be realised. We may expect, therefore, that in tho very near future active steps will be taken to equip France with an efficient broadcasting service with acceptable, programmes, and that a boom- in receiver sales will be created. It is likely, too, that every encouragement will bo given to manufacturers to supply cheap standardised sets for the masses of the poptilation, as was done in Germany in tho case of the "Volks-Empfanger."

It is of interest to note that another minor factor which may influence radio development in France is the fact that that country now shelters a number of competent radio engineers who are exiles from Germany. Because employment in France is, not available to these individuals they are themselves undertaking manufacture there, and although they may be limited in the matter of financial facilities at present, they are well equipped: as regards technical knowledge and experience gained in the very thorough schools of German set production, especially in relation to cheap/sets, of :just .the type which the French Government, will wish to encourage.

TELEVISION

AMERICAN TESTS

Practical tests with an experimental television system which was : used to transmit an' outdoor scene from a short distance and from a-New York studio to Camden, New' Jersey, using an intermediary radio relay station, Were described in a symposium of technical papers on television' presented by research engineers of the R.C.A. Victor Company (May 29), before tho Institute of Kadio. Engineers, convening at the Benjamin Franklin Hotel.

These tests were conducted as another stage in the orderly development of television technique hy the Camden laboratories to determine, the objectives for continued research. Separate papers wore presented on tho transmitter equipment, the New York to Camden radio relay' .circuit, and tho receiving apparatus.

The television transmission experiments fl-ei-o made with the Iconoscope, ■;m ■nici'trical scanning device , having no iiioTing parts anil "Vi'Tib'siß 'openVtioa

[ has been likened to the human eye. It includes a.photo-sensitive screen composed of millions of photo-electric cells upon which is focused tho picture to be tolevised. A cathodo ray beam traverses the screen 240 times progressively from top to bottom at tho rate of 24 frames each second, to present a continuous intelligible image. The use of _ tho Iconoscope in the experiments provided a new degree of flexibility over former methods in that it made it possible for the fist time to successfully transmit outdoor scenes and cover' greater areas in the studio. . ...'..'.

A cathodo ray tube, or Kinescope, was used as an integral part of the receiving system. A beam in this tube traverses the surface of the fluorescent screen in synchronism with the Iconoscope on-the transmitting end, the intensity of the beam corresponding with the varying light..,and\ shadow-1 picked up by the 'iconoscope, thus duplicating tho appearance of the original image. The tests indicated tho desirability of utilising two carrier waves, one for picture and synchronisation, and the other for the sound associated with the picture. In the Camden experiments the picture carrier . was transmitted on' 49,000 Mloeycles and the sound carrier oil 50,000 kilocycles (both about 6 metres). The two receiving circuits necessary for picking np the picture and tho sound carriers, respectively, are electrically tied together so that they operate simultaneously. In <S2ktig a solution to.'the problem of linking together a chain of television stations .to provide a' network service similar [to that of . ordinary broadcasting, tests were carried on between a studio at the top of the Empire State Building -in New York and Cauidoi), using an intermediary radio relay station. The radio relay station picked up the television transmissions at a 1 point between the two cities, re-ampli-fied them, and successfully transmitted them to the Camden transmitter for re-transmission from there. '

LOUD-SPEAKER NUISANCE

An appeal that "a little neighbourly consideration" bo applied to lessen the nuisance of noisy loud speakers was' broadcast by tho 8.8.C. in a news bulletin. Listeners were asked not to place their speakers where the programme could be overheard by their neighbours.

"Sometimes it .is a matter of-too much sound for one loud speaker,* it was. added, "and sometimes it is still more trying when two or more speakers are playing different programmes. : •

"However pleasant each programme may be, they lose their charm when they are heard simultaneously.'. ! s'Tho Homo Office has drawn up a bylaw suitable for adoption by local authorities, whereby inconsiderate use of loud speakers may be made the subject of control. But a little neighbourly consideration should make an appeal to law unnecessary." :

GUT OFF FROM LISTENERS

Lord Derby, owing to a mishap, spoke to himself for some time one uight recently when he thought ho was speaking to millions of listcners-in. He was invited by tho 8.8.C. to broadcast an appeal on behalf of tho--Morseyside Hospital. Council.; . Lord Derby delivered Jiis speech at the Adelphi 110101, Liverpool Later in the evening ho was informed that, owing, .to a-defect in the lini, not at Liverpool, he harl been cut oS soon after the start of his speech. . .

The speech was delivered later in the evening by an official broadcaster.

RADIO PROGRAMMES-

THURSDAY, AUGUST 2. 2Y.A, WELLIXGTON (570 Kilocycles). 5.0: Children's hour, by Big Brotuer Jack. 6.0: Dinner music. Milan Symphony Orchestra, "II Matrlmonlo Secreto" Overture (Clmarosa). Columbia Conceit Orchestra, "The Broken Melody" (Van Blene). J. H. Squire Celeste Octet, "Poter Pan" Selection (Crook). The Philharmonic Orchestra, Berlin, "0 Beautiful Maytlme' (Strauss). 6.25: J. H. Squlro Celeste Octet, "Chant Sans Paroles" (Tschatkowsky). Debroy Somavs Band, "Stealing ■ Thro' tho Classics" No. 3-r-Ovortures. La Argontlna Castanots, with or-' chestra, "La Carrlda" (Tho Bull I'ight) (Valverde). Jean Lonseu and his Orchestra, "Idoale" (Tosti). C.42: Albert W. Ketelboy's Concert Orchestra, "In a I'airy Eoalm" Suite, (a) The Moonlit ■ Glade; (b) The Queen Fairy Dances; (c) Tho Gnomes' March (Kotclbey). J. H. Squlro' Celeste .Octet, "La Serenata" (Braga). ! 7.0: News. - ■ ■ . ! 7.40: W.E.A. Session, Mr. G. Teddie, SI.Se.,1 "The Nature of the Physical Universe: (1) The Idea of Measurement." 8.0: Chime's. Miss Ava Symons (violin), Mr. Hamilton Dixon ('cello), Mr. Gordon Short (piano), "Dumky Trio" First movoment, Lento maestoso; Second movement. Andante; Third movement, Andante nioderato; Fourth movement. Allegro; Fifth movement. Lento maestoso (Dvorak),' 5.26: Kecord, Isobel Baillio (soprano), "Margaret at tho Spinning Wheel." 5.29: International String' Octet, "Octet in E. ■ Flat Major" Op. 20, First movement, Allegro moderate; Second movement, Andante; Third movement, Scherzo; Fourth movement. Presto (Mendelssohn). 0.0: Weather report and station notices. 9.2: Bertram Potts Players present (ho Dramatic Sketch, "Set Free" (Potts). Inspector of Police, Bortram Potts; Jack Manners (chief detective), Charles Morrell; Sergeant Long, P. Bertram; Magistrate, G. C. U Mitchell. 9.12: WaiklM Trio, Hawaiian Instrumental snd vocal. "Hawaiian Gems." 9.20: A- further episode in the lives of "The Japanese Housoboy and his Employer— A Rival Appears." 9.35: Waikllci Trio, Hawaiian lustrumontal and vocal, "South Sea Modley." 9.42: Bertram Potts Players, Dramatic Sketch, "The Kaft" (Potts). Cast: Miss Gladys Graham, Coralie Smythson; Saunders, Bertram Potts; Mr. Gordon Nelson, Charles Morrell. 10.0: Favourites, old and new. 10.30: Danco programme. 11.0: Close down. . ■•■. 2YC, WELLINGTON (S4O .Kilocycles). ' 5.6: Light Musical programme. 6;0:. Close down. ; 7.0: After-dinner music. ! S.O: Concert programme; 10.0: Close down. 3YA, Christchurch (720 kilocycles).—s.o: Children's hour,' by Uncle Mac. 6.0: Dinner music. Percy Pitt and Augmented Symphony Orchoetra, "Poet and Peasant" Overture. Quontin Maclean . (organ), ■ "One Hour. With You" (Whitingl). Monorah Symphony' Orchestra, "Bar Kochba" Selection (Goldfaden). 6.19: New Queen's Hall Orchestra, "Carmen" Ballet Music, Act A (Bizet).r Herman Finck. and his Orchestra, "Offenbachiana." 8.8.C. Wireless Military Band, "Golliwog's Cake Walk" (Debussy). 6.32: Herman Finck's Orchestra, "Schubertiaua." J. H. Squire Colesto Octet, "Moonbeams,and .Shadows" (Squire). . Court :Symphony Orchestra,1 "Tho Windmill- Man." Jean Lensen and his Orchestra, "Love's Last Day" < (Benatsky). 6.52: J. H. Squire Celeste Octet, "The. Ant's Antics" (Squire). Bournemouth Municipal Orchestra, ''The Merry Brothers" (Gennln). 7.0:, News. 7.35: Review of the Journal of ■Agriculture. - S.O: Chimes. ■■ 'Programme— of- ■ records.-• -Regal Cinoma Orchestra,' ."Drury Lane Memories." S.-10: Harry Dearth and Raymond Newell (vocal duet), "A J Sailor's' Philospphy"; "That's Us." 8.18: Jesse Crawford (organ), "Maria My Own" (Leeuoua) ; "Carolina Moon" (Burke) ; "Siboney" (Lecuona). 8.27: Florenco Desmond (impersonator), "A Hollywood Party." 8.33: Anne Welch (soprano), Norton Collyer (tenor) and Victor Conway (baritone), "A Country Girl" Vocal Solectlon. 8.39: The Empire Novelty Band (xylophone quartet), "The Two Imps" (Alford). 8.42: Snedal records. 8.57: Sandor Joszl Orchestra, "Pola" (Fetras) 9.0: Weather forecast' and station ; notices.----9.3: Talk, Mr. George Lawn, M.A., "New Zealand and the Far East." 9.20: The Orchestra* of La Scala Theatre, Milan Hungarian Rhapsody No. 2 (Liszt). 9.28: The Kentucky Singers (male octet), "Swine, Low, Sweet Chariot"; "Witness." 9.34: Mlscha Dobrlnsky (violin), "Serenade" (Porgament) ; "Souvonlr" (Drdla). 9.40: Norman Long (entertainer). "Wo Can't Let You Broadcast That." 9.43: Jack Mackintosh ■ (cornet), "Showers of Gold"

(Charlie). 9.46: Special records.. 10.0: Music, mirth, rtnd melody. 10.30: Dance music. 11.0; Close down.

3YL, Cln-fstchurch (1200 kilocycles).—s.o: Tight musical pvcurrnmme. (S.O: Close down. T.U:■■•At'Uir-dlnnor umsln. S.O: Concert probcammi.'.; 10,0; Close-'doivii.