RADIO NOTES-AND-NEWS.
HONGKONG TELEGRAPH,
Low-Loss Coupler, for Regenerative Reception.
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The most efficient coll for radio, a touch of sealing wax at each reception, one that involves" as ond, -
itilo lose as possible, is a wind Around the middle of this Ingol wiro on an "air ooro." winding, place a plece of thin This loaves the coil itself sup-flexible cardboard, three-fourths ported by nothing except through of an inch wide and just long Its own rigidity as aire
enough for the onde to meet The reason for this is that air around the coil. A strip of In the most officient dielectric or adhosive tape over the joined mon-conductor obtainable. Hard ends would socure the cardboard. Tabber, vulcanite, colorite or any Now out oight' amall blocks of other form of cylinder for hold-hard wood, three-fourths of an ing the ooil etoals some of the inch long by three-eightha high received radio waves from the by three-sixteenths thick. These oof and thus causes a loss in may be stuck to the cardboard at equal distancos around the rocaption.
Therefore, the aim in construct-coll, with a touch of collodion. ing a perfect receiver lies in sook“ Un these blocks and around ing air coro tunors, involving as the secondary goon the printary Httle loan as possible.
winding, consisting of 10 taras of the same wire used for the secondary, Card should be taken that the winding is tight, so that it will net como loose from the blocks. The ends may be secured to the blocks by pieces of tapo, or by sealing wax.
The basket-wound coll, the apiderweb and varieties of those are examples of low-loss culls They consist of wire wound in and out of pegs formed in a circle, leaving not only an air core in the centre, but air pockets or
pacos botweon the windings,
Shunt the sucondary of this coupiar with a variahla condensor of .0005 mfd capacity, and the coupler is ready for tuning in any broadcasting wavelength.
Those colla need special care for proper construction, for they must be able to remain firm and retain their original shape throught ut operation of the
It is an officiant coupler whore receiver. Where the colls are antinod double-circuit reception movable, this diffieu'ty has die-} is required. The accompanying couraged some radio fane from hook-up is an example of the way their use.
in which this coupler may be
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In their stond, therefore, Al-used. It required practically one though not so efficient, is thecom- taning unit, the condenser, be- bination primary, sucondary and cause the tickler is moroly for ticklor colla ---an untuned vario- the control of regeneration. coupler which must sufforslight- JAPANESE WIRELESS OPERATORS, ly more loss than the comploto air- A larger number of wirolons core coil,
operators on board ships ara Only the primary of this awaiting with impatience tho coupler is practically of the air-establishment of broadcasting core varioty. Yet it is much more, stations. They will quit thoir sea officient than winding with, faring Ilfo in favour of positions primary and secondary close with firms to bo established in upon each other, on a dielectric this now line, or establish them- base or oylinder.
nolvos in businoes 'in radio ap- This coupler is made from an paratus from which they hope ordinary 180-degree vario-couplor. for fat commissions. The Kobe Tho Bacondary winding. or Shimbun foars that the shipping zolor, remains as made, and be- companies will havo great comes the ticklor in this instance. difficulty in maintaining the The stator winding is removed) wirolase service, which is vory and in its place should be wound inefficient oven now. We learn 42 turne of 20 8. C. C, wire. from the same source that a plan Number 18 wire might be ovenia afoot among the wireless batter, the heavier the wire the operators at sea and ashore to Joss the loss. The ends of this organise a union and establish a winding may be kept in place by mutual benefit fund,
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BATTERY
BATTERY
HOOKUP SHOWING HOW LOW-1033 0JJPLER MAY BE USED.
PICTURES BY RADIO.
Apparatus on Market.
SATURDAY. SEPTEMBER 13, 1924. (FEATURE – SECTION).
-- The electrical values are... then sent out into space on radio" ORT" rior wavos, justus sound is traDB- mitted. At the receiving" end, Transmission of pletures by these aleatrical waves are caught, radio, long the subjqui of world-converted into light and recordad wido discussion and experiment, on a photo negativo.....
is at last ready for practical use, Thus ono breideasting station says a Washington mossR ZO. can transmit a photograph to as Initial installations are now bo- many points as have the required ing mado and soon the whole receiving
apparatus, powerful United States, as well as other enough to detect the wave of the countries, is expected to be broadcaster. In thie, the photo covered with a not-work of radio broadcasting is similar to sound photo transmitting and receiving broadoasting, tho distance of apparatus..
transmission being dependant on
A company has already been the power of the station, and formed hore for the purpose. It strength of the receiving.sot. establishes and operates transmit- Jenkins expects to go OVOD ting equipment manufactures further. He forecasts the coming and losses receiving apparatus, of radio vision and radio movies and is continuing research work within a few years. In ble for perfection of the machinery laboratory hora, ivo youths Basio patents have been issued are helping him perfect these and others have been applied for. wonders. Combined with audio, Behind this tremendous Jenkins soos the next gonoration
history advanco in, the
of listening and seeing plays and wirolons is C. Francis Jenkins, events onnoted far away. the inventor, who is as famous For the present, the Jenkine in the, motion pleturo field as he installation for broadcasting is in the radio flold. He has the distinction of being accredited the inventor of the first motion picture projector."
CFRANCIS JENKINS, HOLDING THE FRISMATIC RING WHICH HAS ENABLED HIM TO PERFECT AP PARATUS FOR TRANSMITTING PHOTOS BY RADIO.
pictures by radio includes the transmission of mossages, con- tracts and newspaper copy' by this method. Jenkins has been able to flash 100 words a minute in this way. He pradiots 1000 words a minute within a short timo.
NEW LOUD SPEAKER.
A now radio loud-speaker of French origlu is claimed to reproduce speech and music without distortion, giving "quito, unusual distinctness. In placa ofi the stool membrang vibrating before an olostrically controlled permanent magnet, the new in- strument has a little, vibrating cono, which is contained in a fino conical air-gap in a very strong alosed electro-megnotic diroot- jourront field. Tho cone, weighing only twelve grains, has a surfaco of about five square inchoa. It is made of very fuo silk, and its surface is closely wound with fine aluminum wiro, through which passes the electric currant, reproducing the sound. The cone is in the direct-current field of the magnet and the alternating- current field set up in the cone. causes vibrations agreeing.per- footly with the telephone current in froquency.
JOINING METAL AND GLASS. The sooling-in of electrical loads in glass has generally boon accomplished by using a motal
bas a co-officiont of
For the last few years it has boon known that Jenkins had boon working on a method of sending pictures by radio. Others, too, have been busy wish the which same idea, but Jenkins' machine thermal expansion approximately is uniquo.
the same as that of the glass thus platinum and iron wires are used for sealing into glass. But the problem of joining com- paratively large Furfaces of glass and metal together so as to make a vacuum-ti ht joint has boon much more difficult,
The basis of the apparatus is a prismatic ring, or disc, a new optical shape in glass, which Junkins himself designed and can make only by the use of special apparatus. In the sending ap paratus, four prismatic rings are combined, revolving across a light beam directed through a photo negative. These rings slice the rays into strips and convert the light valuus into electrical values.
GECOPHONE
TWO VALVE AMPLIFIER.
THE SINGLE & TWO VALVE AMPLIFIERS
CAN BE USED WITH GECOPHONE
CRYSTAL OR VALVE RECEIVING SETS,
Recently a good deal of success has been attained in this direction by first of all silvering the glass, by obemical silvoring in the usual way, and thon copper-plating on) to the silvering, by means of the electrolytic bath, so as to get a fair thickaoss of copper, and finally soldering the metal on to the copper. Largo sizo wireless transmitting valves, with metal envelopes farming the anade, and water-cooled from outside, haveļ been mado in this way,
A new method has, however, [been developed, which seems to bo oven simpler. The metal to bo coatod to the glass 'us B foundation 19 vapurised by electricity and "firod" out of a
New
QUALITY, STYLE
AND
CHARACTER.
THREE WORDS THAT MAKE
THE DIFFERENCE.
Quality, Style and Character-each
play their part in making our tailoring the very best-care being taken to ensure that individuality is built into every garment we produce.
We aim at perfection and are
not satisfied ourselves until is is
attained.
Autumn
Suitings.
T
THE NEW SEASON'S supplies of AUTUMN MATERIALS
"gun" in the form of a fus comprise some very smart and exclusive designs in
spray. When applied to glass, the metal actually penetrates the |suporficial layers of the glass and gradually forme a very adherent coating. There is no need to bulld; this up by electrolysis, as the layer can be put on sufficiently tblok by means of the blast, and Isoldering can bo offected directly to the deposit thus formed. Tho same process has been suggess. fully adapted to the "soldering " of aluminium to other metals, a layer of copper or other oasily soldered motel being firet deposit- od upon the aluminium by means of the blast, after which the soldering bonomes a straight forward matter. Thia_new proj cess of motal deposition has a great variety of applications out-
very important discovery.
BC 2620, LOUD SPEAKER side wireless, and seems to be s
$48.
HE GENERAL ELECTRIC Co.
JEEN'S BULIDINGS
F CHINA,
HONGKONG...
YOUTHFUL MOTORISTS,
Recording Gatt: verdict » of accidental death "at" the inquest at Twickenham, the other day, on Andrewɛ Quenby, 79, whb: wan knocked down by a boy riding a motors cybla;: the -Coroner, Mr. Kompy said it was open -- to question “Whether spanng 7 Vads Ghould be ableĉtoj hold driving Hoadonke: He thought the Borgin
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IRISH and SCOTCH HOMESPUNS, the products of the
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We shall be pleased to show you the new ranges without obligation on your part or send patterns on approval.
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GENTLEMEN'S and TAILORS BREECHES MAKERS
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