BREWERY
EXPORT
PILSENER BEER
QUALITYS
MADE IN
GERMANY,
SUPERIOR
THE HONG KONG DAILY PRESS, THURSDAY, APRIL 17, 1930.
RADIO
ZEBRA
PILSENER
BEER
LIGHT
PALATABLE
AND
REFRESHING
An
ideal Drink for
the Summer.
Sole Agents:
Gande, Price & Co., Ltd.
No-2 Ice House Street, Tel. C. 185 HONG KONG.
Special attention to Second Class
on the
"ASAMA
MARU”
CHICHIBU MARU" "TATSUTA MARU"
ON THISE FIRST GLASS SHIPS TO AMERICA VIA HONOLULU, THE SECOND CLASS CABINS, PUBLIC rooms, DINING BERVICE AND PARES MAKE A PARTICULAR APPEAL TO THOSE WHO DEMAND COM FORT WITHOUT OSTENTATION.
N. Y. K. ORIENT-CALIFORNIA
FEATURES
MORE ABOUT THE LOUD SPEAKER
54
SOME RECENT DEVELOPMENTS.
THE SEARCH FOR A PERFECT FORM OF REPRODUCER.
[Br "CONERER"
Last week's discussion of the cont has called for a great deal of experiment. Paper, aluminium, speaker dealt mainly with the driv-linen, buckram, and even glass have ing unit.
been tried.
Suitably prepared to give the re- Continuing to the other end of quired stiffness without losing "free- the spindle it is obvious that, work-dom of movement, paper still prOVES the most suitable medium. With so ing plunger fashion, the cone to many differences in design is is not which it is affixed has either got to surprising that one make of cone- be free at the edge, or the material speaker may give remarkably differ ent results to another in perform
of which it is made must have, a
certain degree of electricity.
ance.
coil instrument.
The Baie-Board.
lengthy legal action which has only recently terminated in favour of the defence, for the reason that many makes of conespeaker cannot be purchased complete, the unit and' cone being sold separately.
желе
This and other methods adopted by the smaller manufae turers to avoid an infringement netion. For the same reason very
few makes of moving-coil speaker can be bought complete.
The Moving-Coll.
Recent Developments.
Recently a system of magnetisa- tion without the use of a battery for this type of speaker has been perfected, and may be the means of bringing moving-coils into more general use. Another type of sound reproducer, the electro-static loud- speaker, has lately been invented by Herr Vogt. The principal of the action is known as the differential control. depending on the electrical strain induced by a thin membrane, sandwiched between, two' insulated places of metal carrying the signal or receiver voltage.
The outer plates also carry 000 side (the positive) of a direct cur- rent supply of 700 volts, while the membrane itself takes the negative side of this D. C. supply. The memn brane will normally be in equili of positive potential on either side. brium, having an equal distribution
On the passing of the alternating sigaal current through the outer plates the membrane will be sub- jected to a varying strain, setting up vibrations according to the
A "Talkie" Reproducer, Although this type of speaker is being tried out with great success
The latest modela, all of which are on the local market, have reach- One of the drawbacks to the use A free edge cone, apart fromed such a high degree of perfection of a moving-coil speaker has al-signal current.
that, when attached to a baffle-ready been mentioned, namely the having a bad appearance, brings a board, they are almost, as the separate D.C. supply that is neces- certain amount of weight on to a makers claim, equal to a moving sary to excite the large electro- magnet employed. Another is the delicate spindle. This difficulty is
considerable power required from overcome by either attaching to the
the output of a receiver to drive the epil; usually a special output stage is necessary. circumference a border of flexible material, such as chamois leather, or the most general practice cor- rugating the outer rim. Either method allows for the outer edge to be fixed to 11 suitable frame or mounted in a cabinet without losing the freedom of movement required.
The cone-speaker, to a far greater extent than its predecessor, has provided considerable scope for ex- periment, and at the present day there are so many different designs and materials employed in their construction that it is difficult to imagine that throughout the basic action is the same. The material used for the cane, or diaphragm as it may be termed, in particular,
The use of a baffle-board greatly improves n cone-speaker's tone, and gives the much desired, and hither-
In the case of an all-mains re to lost, response to the bass notes.ceiver, where power is not so limit. ed as in the case of a battery-supply To certain limits the larger the surface area of a-baffle-board the set, these difficulties are overcome and in the majority of factors, made cabinet-sets the moving coil is employed.
greater the response to the lower frequencies. Such a board should, feet square will be found quite a if possible, be of one piece; three
useful size.
The Origin of the dona." The adoption of a conical-shaped diaphragm for sound reproduction
by no means new, having been first patented in 1914. Then, of course, its only use was in a gramo phone sound-box. Applying the principle to wireless reproduction in 1927, only three or four com- panics were granted manufacturing licenses hy the patentees. A well- known radio-manufacturer ignor ing the patent was involved in a
HAVE YOU HEARD THESE?
LONG-WAVE STATIONS.
The action of this type of speaker is a complete departure from the two methods already described.
A small light coil, fixed to the aner of the cone, is placed in the field (or strain) of a powerful
estro-magnet.
The coil being connected to the output of the set, it follows that the variations of electrical energy passed through it will tend to vary the strain it is subjected to by the magnet.
variations will set the cone in vibra- Being fixed to the cone, these tien, giving off sound-waves.
a reproducer for talking films, the volume of sound generated and the dangerously high voltage re quired for its operation render it useless for the ordinary listener At the same time, this or other duction, such as the glow-lamp, may modern inventions in sound repro-
ducer for tome..use, an ideal that be the basis of the perfect repro- has not, in the opinion of the writer, yet been reached. This statement will no doubt be borne out by any reader who has taken a walk along our busiest thorough- fare during broadcast hours. When realising the multitude of sound vibrations, set up in the rendering of, for example, a symphony arches-" tra. it is not difficult to realise that the vibration of one medium is apt. to fall short of perfect reproduc- tion, in spite of the may-be-in- sinstic home constructors. In this.. the-same-room claims of cathu-
the last link of radio reproduction. there is undoubtedly more scope for research than in any other detail of radic reception,
TSANG FOOK PIANO COMPANY,
8, Des Vœux Road Central
(Entrance Ice House Street) Telephone C. 4648.
Simplicity itself
One-motion tuning. Simplified circuit. Units all intercherigo able.
There's nothing lizg
Victor Radio
HONGAY SMOKELESS EGGS GOAL
FOR
HOUSEHOLD USE:
KEEP THE HOUSE CLEAN AND NEAT!
NOTE CHEAP PRICES :-:
In lots of not less than half-ton; delivered to :-
PER TON. Peak District (above Bowen Road) $23.00 Bowen Road and Lower Levels .... $21.00 Pokfulam Road.
23.00 $19.00
Kowloon
Orders should be sent in writing, not by Telephone, at least- 24 hours before the coal is required, and orders must be accom- panied by cash, cheque, or compradore order payable to SZE WAI & 00.
Please apply for prices of other descriptions of coal for bunker, factory, and other purposes.
TELEPHONE" "No." C. 5009.
"SZE WAI & CO.
42, BONHAM STBAND WEST HONG KONG. (CANTON BRANCH-SZE WAI & CO., Lóx Yr SUM ROAD, CANTÓN
'Prose No. 13850.)
BUY BRITISH & BE PROUD
We have just unpacked & Shipamt of
ALUMINIUM BASE-BOARD & PANELS. Suitable for Short Wave Receivers and other saté that require Screening &
OTHER RADIO & WIRELESS PARTS
(Guaranteed British Mads),
ORIENTAL COMMERCIAL & Co., LTD.
BANK OF CANTON BUILDING,
TEL. 0, 4408.:
Here are lists of long-wave and short-wave stations which should be picked up by anyone In Hong Kong who has a mode- rately good set suitable for re- ceiving such signals. Success in picking up these stations also depends very largely upon fav. ourable atmospheric conditions. Readers are invited to add to this list should they succeed in picking up any station not in-- cluded in either of these lists,
BATAL
STATION
Wave length
(Metres) Station
260 Manila
Call
Kilo. "Sign
evcic K.Z.I.B. 1,153
K.S.M.S. 1,085
277 Shangbai 280 Tientsia
C.R.C. 1,070
310 Shanghai K.R.C. 967
320 "Peping C.O.P.K. 45 343 Tokyo J.O.A.K. erd 353 Hiroshima J.O.F.K 950 355 Hong Kong Z.B.W. 8-40 257 Bombay V.U.B. 640
J.O.I.K. 361 Sapporo
830 260 Keijo J.O.D.K. 620 370 Nagoya J.O.C.K. 810 370.4 Calcutta Y.U.C 809.9 350. Kumamoto J.O.G.K. 780 .390 Sendai J.O.H.K. 770 305 Dairen J.D.A.K. 760 393 Rangoon V.U.R. 754 400 Osaka J.O.BK. 730 410 Canton C.M.B.
739 413 Manila · K.Z.RM. 798
SHORT-WAVE STATIONS.
$7.85 Dobintz (Germany)
ÇALL SIGN
AF.X. 60.12 Khabarovsk (Russia) | R.A,97. 18,7 Nanon
60.
Moscow
43.5 42.
Rame
Perth
41.3
Singapore
A.G.J
EF.N.
1.M.A., 6.A.G. Y.S.L.A.B.
38.8 Kootwijk (Holland) P.C.L.
Bangkok (Siam)
37.
$2.0
Bydney
8155
Melbourne
31.49 Schenectady
TIKE (Hose Kona) or, WORKING
4,434 | Mon, Wed; & Fri., 6 p.m. & 2 a.m. 4,000 6-10 p.m
6,291 Not regular
6,000 Tue, Thurs., Sat., 8 pan.
6,896 Bunday midnight
7,142 Daily 8.30 p.m. & 11 p.m.
7,810 Not regular
7,730 Daily 1 p.m.
1
HS4PJ. 8,108 Tuer. & 10 pm-1a.m.
2.B.L.
9.230 Net regular
9,603 Nct regular
WAXAF 9,530 Daily 7 m.
$1.20 Eindhoven (Holland) | PCJ.
31.29 Sydney
2.5.0.
Nairobi (Kenys) 7.0.0.
11,020 Midnight--3 am daily
9,020 FIL 31m. Bat. 1 am, & 10 x.m, 9,590 Not regular
81.
9,677 Midnight daily
28.6
Sydney
:
27.8
Hanila
Band (England) 6.8.W.
2.M.F. P.L R.
10,528 Not regular
18.88 Bandong
18.4
25.53"
24.5
23.35 Schenectady
11,751 7,80 p.m. & 8 a.m. daily, except
Saturday and Sunday
KLIE. 12,240 Nightly W.2.X.O. 12,850 4m. Wed, F, Bat.
18,102 Dally 630 p.m. to midnight" 18,304 Daily 7 pm.
PLO. FC.L. Kootwijk (Holland)
P.L.F.
-17,4 Bandoeng 16.9
17.280 Daily 8 pm, to midnight HL6.1.P.J.17,361 Sundays 7 p.m. & midnight
Bangkok 16.88 Huizen (Holland) PELL
Kootwijk (Holland) P.C.K. P.L.E.
16.3
16.74 Bandoong
15.5
Nancy (France)
13.98 | Pittsburg
17,780 Delly 10 pm:
18.404 Each afternoon 19,220 Daily 6.30-7 p.m.
19,851 Day & am."
W.9.X.K.
21,540 Not regular
TO-DAY'S WIRELESS.
PROGRAMME.
-
BROADCAST BY Z. B.W. ON
|| 333 METRES.
11 to 11.30 am.-Commercial News. 11.30 to 19.30 p.m.-Chinese record..
ed music.
12.30 to 2 p.m.-European Pro- gramme of H.M.V. Records by Courtesy of Messrs. Moutrie & Company.
-
6p.m-Programime of Sacred Music
relayed from St
Andrews Church.
RPOGRAMME. 1-Chorus: O, My Saviour, Fount
of Blessing.
2 Solo Contralto): He Was Dis-
pised.
3--Chorus: Surely. He hath Lorne
our griefs. 4.-Solo (Tenor): Thy rebuke hath
broken His 'heart.
5.-Solo (Bass) and Chorus: May
my heart with ardour burn. 6.-Hymn Cross of Jesus. 7.—Solo (Tenor) and Chorus: At
Thy feet in adoration. 8.-Chorus: From the throne of
His Cross. 9.-Solo (Soprano): I know that
my Redeemer liveth. 10-yma: For the love of Jesus.
Nos. 1, 5, and 7 are from Dvorak's
** Stabat Mater,”** Nos. 2, 3, 4, and 9 are from
del's "Musical." No. 6, 8, and 10 are from
Stainer's "Crucifixion." Soloists:
Little Boy Blue: The Night Has A Thousand Eyes; The Wood- pecker" and "In Winter I Get Up At Night; Every Night: Beat Upon Mine, Little Heart; A Life Lesson" (Ethelbert- Nevin), Edna Kellogg, Sop.- Victor Salon Orchestra. Barchetta; Serenade; Twas A Lover And "His Lass" (Ethel- bert Nevin) and "The Rosary" (Ethelbert Nevin), Robert Sin- mons, Tenor Victor Salon Or- chestra.
8 p.m.-Chinese Programme. 9 p.m.-Weather Report. 10.30 p.m.-Close down..
MORE HIGH-POWER STATIONS,
"It is a curious commentary on the race of high power" which broadcasting authorities in Europe are, now engaged in that it is in part caused by the listening public. in some countries being too poor, to purchase valve sets, and must rely on the crystal set Crystal sets are rapidly disappearing, a condition not to be mourned, for it is re- cognised that they are a handicap to broadcasting progress, Norway has just put into service the highest powered station in Europe, and although Oslo was intended to work on a long wavelength it was found that better crystal range was ob Han-tained with the lower, wave-length. and therefore Oslo will transinit regularly on 493 metres,, which gives in that country on a crystal sets nearly twice the range that the long wave gave. The supremacy, of Oslo as the highest powered station in Europe will, however, soon be challenged, for Russia has nearing completion a 75-kilowatt tranmmit- ter near Moscow, and Crecho- will be Slovakia's Prague station will soon be broadcasting on co kilowatts..
Sprano: Mis F. McGill. Contrato: Mr. Cairno. .. Tenor Messrs. H. Annisa
and J. W. Baldwin. Bass: Mr. C. W. E. Bishop, At the end of the Sacred Music, the following records played:-
(From
PILOT
A. C.
"SUPER-WASP" SHORT-WAVE RECEIVER
THE ONLY SHORT- WAVE RECEIVER NOW ON THE MARKET ON THAT WORKS "ALTERNATING CURRENT.
Tunes 14 to 500 meters. An excellent broadcast receiver as well as the finest of all short-wave instruments.
Particolars from
SINCERE'S
Sole Agents.
WIRELESS FÓR THE BLIND.
A Day In Venice" (Ethelbert Other countries are also remodell- Wireless equipment for 1,000 Nevin," Victor Balon Group.ing their transmitters with the ovalve sets has been offered to the Direction of Nathaniel Shilkret. icct of using greatly increased "Narcissus (From 'Water. Scenes'); power, the ultimate intention being British Wireless for the Blind Country Dance" (Ethelbert to give a wider service, arcp an Fund by various branches of the Nevin) and "A Shepherd's crystal set. But the giant of all British radio trade. The result of Tale; Lullaby
Instations will be Warsaw if the Arendy (Ethelbert Nevin), Victor Salon Orchestra. Dirce tion of Nathaniel Shilkret. "My Desire; Mighty Lak's A Rose" Ethelbert Nevin) and "At Twilight On That We Two were Maying; At Rest" (Ethel bert Nevin), Wilfred Glenn Basa-Victor Balon Group:
Polish plans materialise whereby the wireless appeal made by Mr. the power of that station will be Winston Churchill on Christmas raised to 120 kilowatts. Such a Day is expected to reach a total of power, it is claimed by the technical £10,000. Of,t'e 60,000 blind people experts, would provide daylight above the age of sixteen in England range covering most of the coun- about 10,000 were without wireles try. The parts outlying this large sets. The first instalment of the field are to be provided with relay valve acts offered will be given to Atations.
the blind in outlying areas.