RADIO NOTES AND NEWS
Tuned Radio Frequency.
has Tuned radio frequendy been found the most economical means of radio amplification.
HONGKONG TELEGRAPH,
OT
Tho tubo for this amplifier, of course, should be a UV-201-A, or any other type of hard tube, and It is not only cheaper than the the B. battery should have a volt- transformer-coupled radio frequ-ago of about 90 volts.
Binding posts one, two and onoy, in that a single stago of the former in equal to two of the three are arranged to, most re-
for outsido lattor, but it in canter to operate. ¡quirements
with the con- Going even further than moro loop antends, tuned radio frequency, a clovar denser in parallel or in sorios, little hook-up has been devised by For loop reception, condensor which ofther outside antenna or in paralled, connect one loop ter 100 anno, when the atmos- the other to No. 2, with No. 3 post loop may he used in reception. minal to No. 1 binding post, and photo is clea", the outside antenna shorted to No. 2.
For outside antenna reception, has been found to bost advantage, But the loop has given better condensor in parallel, the connec antisfaction when static interferous are like those with loop and od, or when local interferonco condenser in parallel. However, if the condenser is to bo used in was especially troublesome.
with outside antenna, The bonkun that fallows is de. Į sories, Bigned for both these forms of an.connect binding posts 2 and 3, torna. Its parts consist of the loaving No. 1 opon.
The bost combination for the following.
C1 and C2, two 11-plate varioutside antenna connections will he dotormined by experiment, There is only one way to hookup the loop, howover.
ablo con/lenkerė,
1.1. sporial banned coll.
12, one 1-50 honeycomb coil. Plone 200 to 400-ohm poton- tiometer.
R. one from rheostat. One tuha socket.
One switch and eight switch points.
L
This tuned amplifor will be found effective in blocking oscil- lations froin singlo circuit rovoiver. But due control must | be kept of the amplifier itsolf, with proper use of the poten-
BATTERY
BATTERY
HOOKUP OF TUNED RADIO FREQUENCY AMPLIFIER.
Seven binding posts, bus wire | tiometer, or savoro oscillations and small stool of No. 22 DCC will come from it. wire.
The two condensors should be mounted on opposite sides of the panol.
LOUD SPEAKING FROM A CRYSTAL SET.
when used with any orgstal giving strong telephony. course, it may also be used conjunction with valvo note.
ONE CENTRAL AERIAL.
expert
SATURDAY, NOVEMBER 15, 1924 (FEATURE SECTION),
A
sot double duty, so that although Of only three, valves and a crystal in aro used, the effect produced is |that of a recolver using 'more valves. The ultimate result is {that good, reception can bo obtained from all broadcasting stations in the United Kingdom, Listening-in on East-end Housing and this is, moreover, accomplish-
Estate.
ed without outside serial or earth -a collapsiblo framo aerial, The Housing Committes of which plugs into the top of the the Bethnal Green Borough cabinet forming part of the Council han decided to take equipment. Within reasonable
with advico
regard distancos of broadcasting to the erooting of n central station, tho reception wireless norial upon its bousing sufficiently powerful to operato ortate in order to do away with; a loud speakor. The components
British Broadcasting Company, due to the proximity of the body, Captain P. P. Eckersloy, of the mounted upon a metal panel, thus eliminating disturbanceB and Mr. John Scott Taggart, who and the panel is mounted in a beautifully finished walnut has already propounded a schomo for this purpose, it is understood, cabinet, which, in addition, gives are to be approached for their accommodation to the batteries. suggestions. It is anticipated that required for both and low tension by means of the central aerial supplies, so that it is soon that it will be possible for the owners the receiver is entirely self-con- of the cheapest crystal sots to tained. The receiver makes uso lietanin, not only to the British of the newest type of low-current broadcasting, but to Continental consumption valve (the D. E 3. and American stations.
namorous private aerials.
WIRELESS AT WEMBLEY.
Growth of A New Industry.
which only consumios 0,06 amp.), and in order to avold wasto of current by leav ing the flamerits glowing, the action of closing the doors of the cabinet automatically switches off the supply to the valves.
EXTENDING THE RANGE
It is safe to stato that of the thousands of people who visited the British Empire Exhibition at Radio apparatus, like the ox- Wembley a large uteber saw ponents of a well-known cult of i the exhibits staged by the loading auto-suggestion, seams every day manufacturers of radio apparatus, to be getting better and bettor. In The psychology of this extraor- the earlior days of radio history dinary and almost 'universal tuning coils were of the singlo interest in radio-telephony is at layer variety, wound upon tubular present not well understand, but formers, and toppings were taken it is certain that no innovation and controlled by selector has over uchiavad such a wide-switches. Weird and outber-1 spread popularity as radio broad-somethings they were too 1 casting. The result in industry However, thoy served a purpose has been amazing. All ovor despite certain inefficiencies and Great Britain concorns have many an experimenter treasures sprung up to cope with the ever-a drain-pipo" inductance in increasing demand for the parts affectionato memory of his early] required by the radio onthusiast. offorts.
bo usod
over #
Whilst these have achieved a Of more recout yoark the
introduced certain amount of succose in variomoter,
from various directions it is only re- America, and, no largely used in asonable to expect to find that that country, has bocoma quita the finest apparatus is turned established in Britain 48 011 out by old-outablished firms officient tuning devico. Un- long experience in the manu- fortunately, however, as usually. facture of precision instruments, made the instrument has quite a and whose worke are highly restricted inductance value, and Published statistica of the organised, well equipped and without the addition of loading numbers of radio-receiving sota
nass production. It is not sur-an only Coil L1 may be the primary of sold, show that users of crystal planned for modern methods of colls, unloss of unwidely size, A variecoupler, or it can bo sets outnumbor by far the usors prising thon, anys an exchange, range of 300-500 motros. made by winding 60 turns of other typos of sata, and it is to find that Sterling radio appar-Amongst the many interesting of No. 22 DCC wiro 011 acortain that this preponderance atas is to be found in the den of exhibits on the Sterling stand was tube 34 inches in diamotor. It increano with the growing num- evory radio experimenter, in the an entirely now type of vario- is tanned at overy fifth turn, up to bor of BBC. stations. Crystal home and in public places. This moter, which, in conjunction with the 35th. leaving the oigth tap | rocoption of broadcasting iB apparatus is made with the a small fixed condensor and a open as a tormitial for loop re- undoubtedly vory ino, but same care as aro scientific in-suitablo switch, will cover the coption.
unfortunately, it is confined struments, indeed they are ipso considerably augmented rango of Coil L2, which is an 150 to headphones. Whon friondefacto scientific instruments of 250-2,800 metres. Thus, using honeycomb coil is designad to bo drop in it is vory nice the highest quality.
tho variometer as a tuner (and placed in inductivo relation to the to be able to entertain
them
One of the most interesting it may also be used in a tuned krid circuit of the detector or with radio by means of a loud. exhibits on the Company's stand anodo circuit), it is possible, within three inches of the tuner speaker, and the new Sterling was the now Storling "Throeflex") without adding to the receivor, to secondary In case of a vario- "Amplivox" allows this to be done receiver. This receiver reprosents change from the London station coupler inductance in the dotre-! with the minimum of trouble. a great advance in the design of (365 metres) to the Eiffel Tower, for the call 12 may be sot on the The instrument consists of a com-radio sots and contains several France (2,600 motrés), by merely cabinet abovo the variocoupler. bined loud speaker and valve distinctive features. The circuit turning a switch.
This makes any alterations in amplifier and will give results of embodied is one of the reflex typo, the detector unnecessary.
the most satisfactory natuer in which certain of the valvos do
GECOPHONE
TWO VALVE AMPLIFIER.
THE SINGLE & TWO VALVE
AMPLIFIERS
CAN BE USED WITH
GECOPHONE
CRYSTAL OR VALVE RECEIVING SETS.
BC 2620, LOUD SPEAKER
$48.
THE GENERAL ELECTRIC Co..
QUEEN'S – BULIDINGS.
CHINA
CHONGKONG
USES OF BONE.
Things Mado From Household Waste.
An axhihition intended to illu atrate the industrial value of the bonos collected from houses by the "rag and bono man" was recently to be held at No. 19, |Bedford-square, London,
A first extraction from the raw bone gives the benzina bono krease used for making candles and soap. The polished bone supplies glue jelly.
The degelatinising of the bone) provides the basis of phosphatic manures, used in agriculturo, The bottor quality of degelatinis:] ed bones are calcined and ground up for 180 in pottery, porcelain, and glass factories. In another procese gelatino is made from portions of bones, and in still Another the calcined bono is made to yield phosphoric acld for modi- oinal purpos08;
The koyboard and other parts of a piano are practically put to gether with gluo. Those, and articles of furniture made with glue whon the joints hava to bei | invisible, aro seon, and also the
non-drying glue used by book-| bindors.
Load poncils and rubber pro- ducts in which glue is included are shown, and the uses of the bone itself examplified in such artioles as knife handles, tooth brushos, and rings for bables' comforters. There are also soap and candles, orude glycerine, and numerous articles whose manufabture requires liquid glue -tounie · racquets, oarpet sweep. ors, fishermen's rods, and golf club beads. The agricultural saation containă Vaamples manures and fooding stuffe
All these things are produced from old bonasi enormo
Show your good taste
in the ties your
:
your wear!
It is our pride that we can put before
you, at any time, an attractive selection
from London's latest productions in
FINE NECKWEAR.
NEW STOCKS.
received, by every English parcel mail.
By
the last mail we received a unique assort-
ment in-
NEWEST
KNITTED
NECKWEAR.
Gentlemen who prefer this style should not miss seeing them.
Prices range from $1.75 to $6.50 each, and there is an attractive assortment of colour-
ings in every quality.
BATSWING TIES
IN
FOULARD AND MANY OTHER SILKS.
There are beautiful desigua in Maddor, Paieloy and many other colour offects. Also plain shades.
You will like to see, and we shall be glad to show, without obligation to purchase, our many different styles.
LIGHT-WEIGHT
GOLF HOSE
We have received a new consignment of FINE LISLE
and CASHMERE GOLF HOSE in Khaki, Light Grey,
Fawn, Beaver and Cement. Also Heather Shaden.
CASHMERE SOCKS
IN
Plain Colours and many attractivè disigna
Grey, Fawa, Brown etc.
CELLO and PARIS GARTERS. în tine, nedium
wide weba.
Wm. POWELL, Ltd.
• Gentlemen's Tailors and Outfitters
NO
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