CENTRAL THEATRE
TO-DAY & TO-MORROW
At 2.30, 5.30, 7.15& 9.20 p.m.
A 1931 PARAMOUNT SPECTACULAR OUTDOOR
ACTION-ROMANCE
RICHARD ARLEN
a fighting lover you can't rusist!
MARY BRIAN
the screen's
wwertent sweetheart 1
Zane Grey's "THE LIGHT OF WESTERN STARS
HARRY GREEN
The comic
cowboy!
FRED KOHLER
burly badman of Bancroft's hits.
A 1931 PARAMOUNT PICTURE
Starting Sat., May 2
THE HIGH AND DIZZY COMEDY THRILLER!
HARRY
LANGDON
SLIM
Bubbling and sparkling with fun nad frofiel
SUMMERVILLE
BESSIE LOVE
SEE AMERICA THIRST
Directed by William Craft
COMING SOON
PURE TONE-AND HOW "TO GET IT.
(Contiqued froin, Page 24
No matter what reniedy is made, the cost goes up because of the extra parts needed. In general, therefore, if you know that distor tionis caused by the detector stage try altering the grid condenser and leak values, but do not get too near to power détection unless you can afford to run sugh a rivenit.
With all cleaits there is the chance of getting ilistortion tùroughị ultra sharp tuning. Because selve tivity is so badly needed nowadings many set users are apt to forget w truly sharp their, tuning is. Tuning in general, is far sharper than it was two or three years age and unless one uses special circuits, it is easy to cut off the high notes. The average single riredit tuuer, which needs plenty of renetim to make it tolerably selective, is a bad offentier in this way.
Paramount's Adventuro Film
of Wild Animals
'RANGO
Taken in Sumatra by ERNEST G. SqHORDSACK the maker of “CHANG.”
High-note Loss,
الرسم
As one comes near the oscillation pitt and the aerial dumping is reduced. by slacking off my series capacity in the aerial rad, there is a noticeable loss of high notes. If the set has a low-frequency side which does not give greater man plißention on thews than on thehighs, this H.F. ent-off effect may be counteracted by the low- frequency may sound reasonable: but as the higher toes are de finitely cut off at the beginning, no mount of faking enn reintroduce. them at the end, and if the repro- duction appears, fair then it is only an acoustic delusion.
HONG KONG DAILY PRESS, THURSDAY, APRIL 30, 1931.
KING'S THEATRE HONCKOND'S FINEST CINEMA
SHOWING TO-DAY
AT 2.30, 5.10. 7.15 & 9.30.
BY REQUEST FOR 3 DAYS ONLY
INGAGI
(GORILLA)
With Sounds
A MILLION TURILUS FROM THE HEART OF AFRICAN JURGLE!
CREATURES FOUND THAT ARE APPARENTLY. HALF APE &
HALF HUMAN.
Booking at Theatre, Phones: 25313, 25330.
VACUUM VALVES.
THEIR INDUSTRIAL APPLICATIONS.
†
or
of
out of amplification that can be obtained by means of vacuum tube.
(4) Reutilention.-Current passes through the tube only when the cold elretrade is positive with respect to the hot electrode,
From the viewpoint of these four factors, it is readily secu why the high vacuum tube is such an im- portant factor in radio,
allows an
THE SILVER SCREEN.
QUEEN'S THEATRE.
THOSE THREE FRENCH
GIRLS."
Reginald Denny and Fifi Dorsay head a dazzling cast in "Those Three French Girls," Metro-Ciohd. wyn-Mayer's captivating farre, of: life in Gay Paree, which will open to-day at the Queen's Theatre for three days.
The plot of this talkie force, con- cocted by Dale Van Every and Artbur Freel, is reported to run! tain a laugh in, every reel and a how in every line of its dialogue, which was written by P. Wodehouse, internationally known humourist,
C.
The action centres about the Inn- toring nephew of a British earl, played by Denny, who goes, to Paris for a good time and finds it in the company of two American ex doughboy's and three charming mademoiselles. Complications occur; when the nephew brings the girls) to his uncle's home in the attempt to interest, his righ relative in back. ing a modiste's. shop,” All woukl have gone welf had not the uncle fallen in love with the very girl whom the nephew had picked out for himself. But all the difficulties ire ironed out in the end in a rol licking manners,
RS
Cliff Edwards and Edward Brophy are reported to be nothing less than a sercam " the two doughboys who want to see what Paris is like without M. P.s George Grossmith and Peter Gaw- thorne are said to be equally funny ns the befuddled earl and his cock- ney butler, respectively, while the remaining members of the girl trio. Yola, d'Avril and Sandra Ravel, add their dralferies to the lot.
NEW MOON."
"
electrons and positive ions may be men who were drilled personally ay allowed to tenvel to the anode. † Generát Theodore Lodi, late of the This is accomplished by surround- | Russian Imperial Guard. 'The pie ing the hot cathode with heat inture was directed by Jack Conway sulation and heat reflectors, with only relatively small holes to allow the passage of the current.
· By such means, we only have to pay" about one wait per ampere for our current through the "tube, rather than the 10 to 150 watts per ampere.
Also, this urutralization of the space-charge which results from the introduction of mercury vapour or gas eliminates the high voltage
the necessary to pass
eurrent
large supporting enst is handed by Adolphe Menjou; Roland Young, Gus Shy and Emily Fitzroy,
"New Moon" will be the attrac ton at the Queen's Theatre starting on Sunday.
CENTRAL THEATRE.
"THE LIGHT OF WESTERN
STARS."
Richard Arlen in
.sren
swaggering, bragging and wholly lovable lover in his featured rôle in
"
MOVIELAND
FOR
THE WEEK?
QUEEN'S
TO-DAY TO SATURDAY Ar 2.30, 5.10, 7.15 & 9.20.
PARIS BOUND!
Brodakon
ted
You should arrange your thing so that, although, it is selective, it does not aller the tone. In
(3) Voltage Control-Relatively This neitralization of the space efficient tuning coils may need a
large amounts of current through allows a very different design of lot of renetion to make them selve-|
the tube can be controlled by hot cathode. Instead of having to. tive, while a properly designed coil
| voltage on the grid without the utilize what might be termed qu Russian military maneuvers cam- may give quite good selectivity
necessity of furnishing any current open type of cathode for the electuanded by are netual Russian without the necessity for forcing
to this grid. For instance; the trons to leave the hot surface ensity, | general, figure in "Now Moon," reaction and thereby losing quality. À vacuum tube may be classed as electricity generated by rubbing ait
enclosed type of Metro-Goldwyn-Mayer's adaptation There is always the possibility of to:-(1) Number of electrodes. A fountain pen with a piece of cloth, cathode with just a fow holes for the Broadway stage success co- using a band-pass` foran of circuit.
two-electrode is called a diodes when applied to the grid, is auf-the stream of neutralized and mega-starring Lawrence Tibetd and Grace High-frequency valves can cause three-electrode tube a triode; and heint to contrál félátively large tive ions to pass through.
Moore. Tillt ILK Д Tusalan a great dead of distortion if wrongly som to include a tetrinle and a
amounts of power. It is this fea This menus that the heat many be Feutenant in the vivid drama of (2) The content of the used, particularly on fairly weak pentorie.
ture that results in the large kept in and conserved, whereas the adventure and intrigue commands stations, which on good set bulb, which may be high vacua, an be tuned in at loud-spenker gas or vapour. (3) The nature of electrole, the strength with quite reasonable the fundamental purity. Screened-grid valves are cathuk, which may be thermionie, frequent offenders because they are photo-electric, mercury pral, sometimes operated" on
ahndly cold, chosen part of the characteristic, Practically any form of the nunny Trane out the grid eirenit conice-Types of vacuum tubes can, for con- tions of your screen-grid valve and venience, be classified by a combing break the return fond to the negation of these three properties. For tive of the filament. Insert a small instance a bulb which is sold under
The high vacuums tube, however, -volt cell here, or, alternatively, the trade mark of “Tungar" is 'a take a flexible taping out to the gas content, hot-enthode diode. The has for industrial application cor |'grid-bias battery used for the low-screen-grid til used eu much in tain aerius imitations. A very quency side of the set. You ring modern radio is a hot cathode, heavy price, in the way of power find it necessary to put a small con-high-vacuum tetrode. The small boss, must be paid for the current denser across this grid bins tapping, tubes which are sold under the thut it carries. As has been stated to keep the H.F. currents away trade mark. of Thyratron" are above, the current through the tube through the space, and instead of from the batters, and this condenser hot-eathode, mercury-vapour trio in governed by the electron emisa large voltage increasing with the sion and the space-charge effect, amount of current to be carried,
The Light of Western Stars, should be close to the H.F. side 80 | drs.
which latter is simply another way there is a constant voltage loss of
which opened nt that the H.F. evrente are by-pa85-
the Central Fundamentally, the amount
Theatre Inst night for a three days' ed long before the bing battery is current that ens be carried through of expressing, the voltage loss in only about 10 to 20 volts.
With a part closely resembl- reached. A microfarad axed con- the vacuum in a hol-cathode, high carrying the current through the
It is, therefore, apparent that
denser is ample.
vaenum tube is dependent upon tube. To make the cathode hot so for the handling of relatively high ing his inimitable role in "The currents, such as we have in the | Virginian,' Arlen gives a great High-frequency valves are apt to what is termed the "electron emis that it will mit electrons requires broad field of electrical engineer portrayal in this Zane Grey out- give two ather distortion troubles.sion " and the
ing, the gaseous type of electrodour action-romance. "space charge electric power. This is of the order They are apt to pass on stray high effect." In other words, to get of 10 af 150 watts loss per ampere statically-controlled Lube is much
better suited than the controlled Mary Brian in the heroine of this frequency corrents which upset the current through a vacum, the of current through the tube.
high vacuum type.
thrilling story and she is here every Considerable voltage is also re-
It is true that a Thyratran tabe bit as sweet na she was in The working of the detector and low proper amount of electron emission
quired to carry the current across has certain limitations. As has Virginian," or in "Burning Up," frequency stages, and, secondly, be- to supply this current must be of the space, the order of magnitude bean stated, the high vacuum type in which she was seen with Arlen cause of the enormous amplifiention tained, and also the proper voltage being several hundred to a thou-of tube can handle currents up to recently. The story is exciting and
and replete kaid volts for one ampere. From the frequency of a million eyeles fast-moving,
with possible with modern valves, the and the arrangement of electrodes this, it will be seen that currents per second, whereas the Thyratron spectacular scence, such as a gigan detector is needlessly overloaded. must exist to permit this current of more than a low amperes cannot in its present form is limited to a the wild horse stampede which would to pass with the available, voltage," be handled economically by means few thousand cycles per second.
Le hard to match for realism and H.F. Troubles..
Also, the Thyraton cannot control startling beauty. The current through the tube may of a high vacuum take," The first trouble enn be prevent be limited either by not having Therefore, it is apparent that the direct current in the same simple "The Light of Western Slara " most promising applications in the way as the high vacuum tube; that in novel forta was one of the best- ed by having good H.F. choke ar-sufficient electron emission or net
having sufficient voltage to pass the industrial field for the high vacuum is, it lacks the feature of con- | Bellers of the year. Paramount has rangements, and perhaps a atopper described current.
tubo in various control opern- tinuous control." However, it captured the true spirit of the mov- rekistanes in the grid lend of the The introduction of the grid is tiong where some of the unique happens that just the high ing story. Arlen, a young cattle first, low-frequency valve after the simply & method of controlling the characteristics listed above, rather vaenum tube fitted remarkably well foreman, in a moment of despern than its output, are the determining into the radio communication field, tion, vows to marry the first white space-charge factor. detector. Also an HF. stopper
the Thyratron tube appears to fit woman he meets. That woman Taking up next the Thyratron admirably into the industrial en-happens to be Mary Brian, who re- circuit can be included in the anode
tube, its striking characteristics gineering field.
sents his insult. In a succession of, lead of the high-frequency valve.
As a good example of this, con- adventurous events, Arlen manages (1) Independence of frequency, are the greatly decreased amount If the H.F. valve is a three-clee Electrons are so rapidly moving of power required to heat the sider Radiotron UX-250, a high to offset his initial pour impression "trude with aperiodic choke coupling, that they will respond to frequen cathode, and a marked reduction in power loud sponker tube that was and wins the girl.
cies of the order of several million the Inrge voltage drop which is used a considerable extent with There are Beveral excellent as is popular in many transportable cycles per second so that for most characteristic of the high va u some of the early dynamic sneak-hamorous réfes in the story, por- sets, then the provision of a stopper purposes, the tube kas no limita- | Lube, This is brought about byers. A Thyraton tube built to circuit often improves the quality. tions in this respect.
the introduction of a very slight about the same size and costing trayed by Harry Green, whose The second point, overloading of
(2) Continuous control. The lee amount of gas or vapour into the the same amount as this Radiotron dialect comedy is funnier than ever in this strange setting, and by Wm: trous each entry such a small charge bulb This eliminates what we will handle approximately 50 times LeMaire, the garrulous sentinel of the detector by the H.F. valve, can and move so rapidly that the cur-have termed "space-charge" which the current.
Fred Kohler "Only the Brave." These are the reasons which gives be cured only by fitting an HF rent through the tube enn follow in reality is the mutual repulsion volume control. This can be m very complicated wave form between the electrons due to their us complete faith in the applica furnishes the thrills as the bad-man rheostat in the H.F, valve filament smoothly, as distinguished from the negative charge, that has to be tion of the Thyratron type of tube who comes between Arlen and his
step by step action that occurs in overcome by the use of considerable in the broad industrial engineer girl. lead (it should be in the negative most other pieces of electrical ap voltage and which introduces ning field to the same amazing ex- side), or an aerial" volume conparatus. It is this feature that has power lops The positively charges fent that, the high vacqum type of trol may in fitted.-Amateur Fire-made the high vacuum tube so mercury vapour or gas molecules type, developed around the pliotron useful in long distance telephony mingled with the electrons, neu idea, has dominated the radio com- and radio broadcasting,
tralizing this space charge.
munication and broadcasting field.
Booking at Anderson's and the Theatre (Tol. 25720).
less.
A high vacuum tube has four fea-factors. tures that singly or in combination make it a unique electrical device.
R
Embark
on à voyaga
of thrills in
this eye-full, ear-full, laugh-full faroo Flot!
with Fifi DORSAY Reginald DENNY CLIFF_KDWARDS, YOLA D'AVRIL, SANDRA RAVEL, GEORGE GROSSMITH
*Metro
Blant
flat o stritj
Charmaine (2 Javolvate
Those
THREE FRENCH GIRLS
NEXT CHANGETM
Drama!
Music!
Romance!
TIBBETT
Lawrence
MOORE
Graces.
NEW MOON
most glorious voices are now heard to gether for the first imel
The screen's
Walt till you hear them
sing "Lover Come
Back to Mo"}
with ADOLPHE
MENJOU
ROLAND
YOUNG
directed by
CONWAY
JACK
"The Light of Western Stars.”, is
well worth seeing for its romance, its thrift pretzels, or its lumour, but chielly for its great all- round entertainment.
Metro-
TALKING
IN