CROSSE & BLACKWELL
FOR QUALITY
Here are three good lines:-
OX-TAIL SOUP,
in 10 ounce tins.
BRANSTON PICKLES.
SANCHOVA.
ft
The ideal fish paste for Sandwiches..
Obtainable at the following stores:;
Lane, Crawford, Ltd. Sincere Co., Ltd. Wing On Co., Ltd. Sang Lee.
Man Fook Shing.
Wing Tai. Kwong Yuen Mow. Kowloon Store.
THE HỒNGKONG TELEGRAPH. SATURDAY, MARCH
OSCILLATION IN
WIRELESS.
USE OF ADJUSTABLE REACTION.
·MANY ADVANTAGES.
["Morning Post" Wireless
*Correspondent.}
So many advantages are obtain- ed by the proper use of adjustable reaction that one would not sug gest receivers should be built without it. A user soon learns how much reaction can be used without imparing the quality.
rible. With one of these valves ja "high-frequency, stogo can be applied to the node circuit of the valva in such a way that even |when the anode eircuit is made to |oscillato, ho'oscillations are trans-
mitted to the aerial. .
The shielded valve has the usual flamont, grid; and anode, and in addition, a shield in the form of a. wiro mesh, which is mounted: between the grid and anode. The shield is connected to the high tension battery and has the effect of making the capacity of the grid. to anode very small indeed, This valve may therefore be used with perfect safety in a circult having adjustable reaction, but it is necessary to shield the tunning colls and condensers,
The Shielding.
1928
DOCKYARD · STAFF. OTOG PH
"Some of the Staff of the Expense Accounts Department at the Hongkong Naval
recently. (Photo: Ming Yuen).
"POTIPHAR'S WIFE” BANNED AS FILM.
The shielding prevents currents The difficulty, of course, is that passing direct from one circuit to reaction as normally fitted enables a user to create oscillations in the another, and, in fact, when the circuits of the receivor convected
Jahielding has been properly to the aerial which radiates them. carried out and the circuit cor- The main disadvantage of adjust between the circuit that is con
rectly designed, the only coupling able reaction would be entirely nected to the aerial, and that removed if means could be provid- which is connected to the detector ed for preventing the locally pro- that due to the almost negli duced oscillations from reaching gible capacity of the anode to grid. the aerial. Fortunately it is now possible to do this. A valve con
It is not difcult to shield tuning nected to work as a high fre circuits, but care has to be taken quency amplißer can be connected that the efficiency of tuning coils between the aerial circuit and the is not materially reduced by the efrenit, that has the reaction shields. The affect of placing a applied to it.
piece of metal near a tuning coil When an ordinary receiving is to reduce its efficiency by an valve is used difficulty is always amount which may be serious if experienced because the valve the coll in the first place was a itself provides a coupling between good one. The effect is more Middleton's "pyjama play," which the circuits, and further, the cir- marked as the metal is brought played to packed houses in the cuits that are connected to the closer to the coll, A designer, Westend, has been banned for film valve tend to oscillate without the therefore, endeavours to make a purposes in the United States by addition of adjustable reaction. shielding box as large as possible the Will Haya Organisation."
News to this effect has just been Various balancing arrangements in order that it shall be a reason- tire used to stabilise a high freable distance away from tuning received in London. The First National Company, which had quency amplifying stage, but the colla.
acquired the screen rights, will now be unable to exercise them.
NOT TO BE PRODUCED IN AMERICA.
"Potiphar's Wife," Mr. Edgar C.
Will Hays is the president of thej Motion Picture Producers and Dia- tributors Organisation, and the autocrat of the American picture
balance can rarely be made so per- When space is important and feet as to prevent entirely a the shields have to be made of coupling with the aerial circuit. small size, it is customary to use In other words, when a high fre- specially made colls. An ordinary quency amplifying stage is fitted tuning coil comprises a covered in front of an ordinary receiver, wire wound on a tube. In order industry. "The Green Hat," which comprising a detector with reto reduce the effects of metal in to be produced here by an Ameri- action and low frequency stages, shielding, a coil is often wound in can company, was aimliarly banned there is still a tendency for the two parts. One half of the coil by the Ilays Organisation. aerial circuit to be influenced by is wound in one direction' and the "Potiphar's Wife'. is not a the detector circuit.
other half is in the opposite direc. play" said Mr. Middleton "but tion. Such a coil la not influenced that the vulgarians who control the Oscillations.
so grently by shielding as ondestinies of Hollywood should find Even when the circuita are ordinary coll, but as one would themselves in the position of con- shielded by placing the various expect, the efficiency of the coil sors of morals strikes me as being coils and tuning condensers in wound in two parts is not as great the grimmest joke in this topay- metal boxes, there is still a ten- as the ordinary coil. But the turvy world of to-day♬ dency for oscillations to occur. efficiency of the coll wound in two This is due to the fact that the parts when mounted within the parts of a valve have capacity, shield may be greater than that Inside an ordinary valve is a of the ordinary cofl under the filament, grid, and anode. The same conditions, grid is usually formed of a flatten-
ed coil of wire, while the anode-
Special Coil.
Because of the simplicity of the circuit it is possible to dispense
THE CHINA EXHIBITION.
Wet weather marked the opening of the China Exhibition on Wednesday, but considerable interest was taken in the function arranged by St. Andrew's Church. "One of the stalls ja seen in
the picture above. (Photo: Welcome Studio)..
ULTRAVIOLET RAYS FOR CHICKENS.
INTERESTING RESULTS IN
'SWEDEN.
of the radiation can be measured and evidence about this feeding method gained.",
Another interesting experiment has been made to ascertain the nutritive value of stored fodder, prepared with electricity. Excel- lent results have been obtained, but has proved rather Expenälvą. : The effect of the long and Electric light during the Win- with plug-in colla,, and switching dreary winter and of the lack of ter month as a substitute for can be used to alter the circuits) sunlight is now being counteract- bright day-light has yielded ex- is of sheet metal shaped in the The special coll has what is from the lower broadcast band to ed through the scientific use of cellent results both in poultry- form of a box with open ende. known as an aetatic winding, and the higher.
electricity in Sweden. Interest yards and bat-houses, where the The grid and anode are quite close there is a tendency for more of oudspeaker reproduction of many violet rays to chickens are being correspond to the dawn and Such a receiver would give ing experiments in applying ultra-light is generally adapted so as to together, and therefore have capa- these colls to be used in commer-distant stations. Tuning would carried out at the experimental bwilight. Expecially for bulbous city. The tiny condenser go form- eial receivers. ed acts to couple the anode and A receiver comprising a stage of be easy, and there should be no station of the Department of plants and cucumber this bas grid circulls, and in many high-frequency amplification with reason at all why the quality Agriculture in Stockholm. Every proved of great value, but flowers instances causes unstable working. a shielded valve, having properly should be other than acceptable to fortnight out of the eggs hatched too have. yielded extremely
The shielded valve that is now shielded circuits, a detector and critical listeners.
five groups of good results in this way. One or two manufacturers are at this station
marketed has been designed to re- two low frequency stages with re-
duce the capacity of the anode and action from the delector circuit to already producing a set of this chickens are fed with exactly the At Christmas the electric hot grid ander working conditions to the anode coil, is capable of a very type, and no doubt by the autumn same rations, while only two of beds of Sweden gave big and an amount which is almost negli- Jine performance,
others will have designed similar these groups are exposed to ultra- beautiful flowers similar to these
violet rays. . In this way the affect of Midsummer.
receivers:
READ
"GIRL
ALONE"
By
ANNE AUSTIN
Gett
The Food of Kings
Court Physicians know the best and see that Royal Babies have the best. That is why Glaxo has been used with success in 5 Royal Nurseries. Only the best is good enough for your Baby, for is he not a King to you? Give him Glaxo, the food that contains everything that will build firm flesh, strong bone and a sound constitution.
Glaxo
Tha Vitamin Milk Food -
"Builds Bonnie Babies
Sole Agents:-
W. R LOXLEY E Co.
E. HING & CO. SHIPBUILDING MATERIATS, SHIP CHANDLERS
HARDWARE MERCHANTS.
PHONE
-CENTRAL No. 1116.
Wing Woo sizODE
TEL Central 25.
In The
“Telegraph'
Beginning TUESDAY
APRIL
3rd.
"