Trade Displays at the Exhibition

Radio Record, Volume III, Issue 15, 25 October 1929, Page 28

Trade Displays at the Exhibition

. Details of the Stands

LL INTERESTS have been eatered for in the forthcomihg Auckland Bxhibition. Radio traders are preparing their stands, some for the amateur constructor, some for those who are interested in small sets, while the remainder for those who require an up-to-date receiver of modern design. The allocation of the. stands is as follows: No. 1 Society. No. No. No. No. No. No. No. No, COONS Oli Go bo Amateur Radio Transmitting Moore’s Piano Co., Ltd. Lewis Eady, Ltd. Hartle and. Gray. Philips Lamps. Harringtons, Ltd. "Radio Record." Superadio, Ltd. Superadio, Ltd. No. 10 Bond and Bond, Ltd. No. 11 J. Wiseman and Sons. No. 12 Frank Wiseman, Ltd. No. 138 Abel Smeeton, Ltd. No. 14 Abel Smeeton, Ltd. ‘No. 15 Radio, Ltd. (Cossor). No. 16 Selectra Radio. No. 17 Radio, Ltd. . (Steinite . and Ultimate). No. 18 Amalgamated Wireless, Ltd. No. 19 Spedding, Ltd. No, 20 Farmers’ Trading Co, No. 21 Johns, Ltd. No. 22 New Zealand Radio. As far as possible, detailed accounts of these exhibits have been collected. These appear below. There are a few vomissions due to the owners of these —

stands not having the necessary information available as we go to press. Full details will, however, appear in the issue immediately following the closing of the exhibition, that is, the one dated November 8, Stand No. 1. AMATEUR TRANSMITTING ASSOCIATION. HIS stand, belonging to the Amateur Transmitting Association, will certainly hold more than a passing interest for the public in general, and to amateur transmitting enthusiasts the-display will prove all-absorbing. Short-wave equipment for both transmission and reception will be exhibited in ‘variety. A splendid record will be revealed by the amazing number of Q.8.L. cards received by the assdciation and displayed by them on the rear wall of their stand. Stand No. 2. MOORE PIANO CO. Tus firm, realising the difficulties that Auckland listeners are faced with in regard to direct current supply, are arranging a very complete exhibit of rotary converters. The function of this apparatus is to transform the direct current supplied to the home into alternating current that will energise —

an AO receiver. With the increasing popularity of this type and the impracticability of completely: mains operated DO sets something of this nature is essential. , These rotary converters are giving excellent service in many parts of Auckland, in fact most of the lead‘ing firms are using them at the present time. Listeners then will be pleased to see this exhibit and learn how they can have the most modern conveniences even though separated from the means of attaining them by what on the face of it appears an inseparable gulf. The principle of the rotary converter ‘is somewhat complicated. As the directcurrent voltage is dependent on the al-ternating-current voltage of supply, variation of the field strength as a control for the power factor is not used. The field, however, is permanently adjusted to hold the power factor reasonably . near unity. Independent means are. provided for so adjusting the applied alternating voltage as to give the required result at the commutator. Stand No. 3. LEWIS EADY. ‘HE exhibit covers all the latest Mullard productions, including the A.C. types. Other valves in Mullard's latest productions are the screened grid, pentode, and special detectors in _-

the 2, 4, and 6-volt types’ which are proving so popular. The latest Magnavox production incorporates the exclusive Magnavox X-core principle which enables the manufacturers to give a lifetime guarantee of original standard of performance. An addition ‘to the Magnavox range is the 104in. Auditorium Cone in 6-volt and 110-volt to 300-volt D.C. types, besides the standard 230-volt A.C. types. The new Webster pick-up will prove very interesting to those who ‘can tise the audio stages of their receiver in conjunction with an ordinary gramophone. There are many improvements in Webster’s new product, one specially fine feature being the ease With which needles can be inserted and replaced by merely twisting the pick-up head. With the volume control in the base and the very fine finish and design of. the new Webster pick-up, it offers splendid value. HE Burgess exhibit displays a wide range of types in both radio and flashlight. Burgess manufacture sizes and capacities suitable for all purposes from the small portable for portable receivers to the large "super" which gives an extremely long life on seven and eight-valve sets. Those who have heard so much about the Majestic and who have not examined it will'have an opportunity © of seeing and hearing it perform at . the stall of Messrs. Lewis Hady, Limited. The new model Majestic receivers and the combination gramo- =

\ phone and radio receiver will prove interesting, to intending purchasers of electric receivers, Stand No. 4. HARTLE AND GRAY. JN accordance with their policy of eatering for the home constructor, a large portion of this stand is devoted to components. Practically every British maker of radio goods is represented. In addition to the ordinary components, there will be a moving coil kit set of the Baker pattern. This will very much interest the amateur constructor, who considers that the eonstruction of a moving coil loudspeaker or task beyond his capabilities. The ttery of the London Battery Company provide a novelty in the unit construction of B batteries, Other novelty lines include loud-speaking telephones, a complete experimental radio vision equipment, power equipment for public address work, and microphones. The radio vision should evoke much interest, as this will be the first time that the public will be able to see this apparatus. The sets include the All-Hlectric Five, a British product, which has one, stage of screen grid radio frequency, This set operates without an aerial. A combination radio set and ‘gramophone is also provided. In the battery operated sets the All Purpose Four provides a very fine example of good work in small space. This set is designed to cover all frequencies, and being small, is readily ‘transportable. Other sets will include many popular smaller models, well known to the radio public, and of undoubted int

terest to those who are contemplating taking their first plunge in radio. Stand No. 5. PHILIPS LAMPS (N.Z.), LTD. NOVHL title has .been selected for this stand-the name will be built entirely of Philips valves, defective ones that we are assured that all New Zealand had to be raked to secure énough. One of the new Philips products for the season is the A.C, 333. This simple, but efficient, wireless receiver is the newest innovation of its kind. That it is already very well known and well patronised in Australia bespeaks its quality. This receiver using the new Philips A.C. valves gives wonderful reproduction from a strong station, and _ visitors should not leave the Exhibition without first seeing this ‘compact little set, and making inquiries about it. There are other kit. sets, including the latest four-valve version. This new model will be sure to win the approval of the home constructor who wants a good set for a small outlay... There will be also the QPAC receiver for local reception. This operates without aerial or earth. Philips valves, speakers, condensers, transformers, and gramophone pick-ups will also be on view. New models of these have been brought out recently and will no doubt appeal to all who are competent to judge radio components. Stand No. 6.

HARRINGTONS, LIMITED. RELABLE power-packs can now ebe obtained for furnishing all current required in all-electric receivers, and those who wish to construct their

own will be interested in the demonstration of Pilot power-packs. The power-pack -consists of three distinct units, the transformer, condenser block, and a double choke. All three units are very compact, each being approximately 54 inches high, 5 inches long, and 3 inches wide. All three are mounted in substantial steel cases, and all connections brought out to moulded bakelite connections, The transformer block incorporates five secondary windings for both filament and power supply. The. former are provided with centre taps, so that the necessary "O" bias voltages can he obtained by taking the voltage block across the fixed resistors connected between the centre taps and the grid returns of the amplifying transformers. The transformer has_ sufficient carrying capacity to supply the_requirements for five or six UX222 valves, three 227’s, and two 171’s. The high voltage will supply 60 milliamps at 20 volts. ; The Pilot Super-Wasp kit, which may be assembled by any amateur, covers both short-wave and broadcast band. It is claimed that this receiver does not suffer from any of the usual defects of either home-made or secondgrade kit sets. The circuit incorporates a stage of radio tuned frequency, an automatic aerial change-ovér, a 222 screen-grid valve, a 201A, detector, and a 171A in the last stage. The stronger .short-wave stations may be heard on the loudspeaker. Both these exhibits. will, no doubt, be of great interest to the amateur constructor. Stand No. 7. »

"RADIO RECORD." T the time of going to press we are unable to give full particulars of our activities in the exhibition. We are hoping to have on show sevéral of the popular models that have appeared in our paper and which will appear in our handbook, "All About the All-Hlec-tric." There will be available supplies of this publication, the "Listeners’ Guide," and the "Radio Record." The technical editor will be present, and will be pleased to discuss any problems the visitors might have encountered. He also wishes to make the acquaintance of his many pen-friends. Stands Nos. 8 and 9. SUPERADIO LIMITED. QUPERADIO ‘have for some considerable time been the agents for the Dayton Receivers, and they take the opportunity of the exhibition to introduce the new A.C,,Dayton "Navigator A.C. Receiver." The complete assembled unit is of the conventional Console design. The circuit ealls for a few comments. It utilises the new Technidyne system of free selection, wherein the energy from the station being reved is completely filtered and selected before amplification of any kind takes place. By this method extraneous noises are reduced to a minimum, while selectivity is greatly enhanced. The new method of detection (called Power Detection) enables the circuit to obtain an output from the detector equal to an ordinary detector and one stage of audio in the ordinary circuit. The output from this is fed directly into a push-pull stage, utilising the new 245 type of valves, together with an especi-

ally designed 11-inch dynamic cone. All A.C. hum is eliminated. The dialtis calibrated in both numerals and kilocycles. Connections are provided on all models for gramophone pick-up. There are three main divisions jn the circuit: the selector, the amplifier, and the power unit. Directly behind the tuner are the shields carrying the tuning coils, and behind these is the amplifier unit, containing the five radio frequency amplifying valves (all 227’s), and the detector. There'is only one connection between the amplifier and the selector, which can be very quickly removed, and which will thus facilitate service. Rectification is carried out by a single 280. The valve sockets are coloured, so that a mistake cannot be made when fitting new valves. In addition, Superadio will be exhibiting other well-known products, ins cluding ‘Magnetic and Dynamic Speake ers, Batteries, Eliminators, Valves, ete, Stand No. 10. BOND AND BOND. WO distinct types of radio receiver are marketed by Bond and Bond, and these will be represented in the exhibition by the latest models. Great emphasis will be placed upon the new Silver Radio, This is the latest product of the Silver-Marshall firm. It comes to New Zealand in two distinct units; the chassis and the cabinet. ‘By packing them separate by the manufacturers elaim that damage to the receiver is impossible. The cabinet follows the usual lines of the modern receiver, and is distinct in two models, the Highboy and the Lowboy. Several unique features are claimed for the.Silver Radio. It is.sharply selective, und is yet very sensitive. Electrically the receiver con sists of three stages of radio-frequency amplification, using A.C. screen-grid valves (Ceco). The detector embodies. the very latest system of screen grid ‘power detection. The following audio valve is resistance coupled to this detector. Following this is a pair of 245’a in push-pull. The stages are connected by a 1-to-1 transformer. The power unit supplying A, B and © power is self-contained within the set, and consists of the usual tranformers and filters, The first R.F. valve is coupled to the second through a tune stage consisting of two separately tuned circuits. This. produces a "humped" resonance. curve of extremely ‘steep sides and broad tops. Four ganged condensers tune the secondaries of the radio-fre-quency transformers. The sensitivity of this receiver ig such that Australian stations can be tuned in by using a piece of perforated metal as an antennae. Apex receivers and speakers will be exhibited, and will command the attention of those who are looking for 2 small, yet powerful, receiver. Stand No. 11. J. WISEMAN & SON. Af WISEMAN AND SON have made * their reputation in New Zealand radio world by designing and marketing the now famous Courier Radio Receivers. The first Courier was a small D.C, set,. introduced over 18, months ago, This was remarkably successful, and Messrs. Wiseman followed up their success in this line by others which have in turn earned great fame, The set of last season was the QR3, a popular three-valve set, which was capable of bringing in all the usual sta-

-_ tions. Its unique cabinet enabled the batteries to be placed inside, and thus unsightly leads were done away with. One of these models will be on view at the exhibition, and those who consider the all-electric as impracticable will be greatly interested in this receiver. With the advent of the A.C. receiver, it was necessary to provide such ‘a set in the Courier series. In due course this receiver made its debut, and has met with the success of its predecessors. At their stand in the exhibition, J. ‘Wiseman and Son ‘will display their factory receivers in various stages of their manufacture, Their technician, who is responsible for the designing and manufacture of the Couriers, will at different times be in attendance, so that visitors will be able to see personallv the originator of this very find receiver. _ Other items of interest displayed will be various components which should draw the attention of every setbuilder. Stand No. 12. FRANK WISEMAN AND SONS, ‘A TWATER Kent Receivers will be featured on this stand, and visitors will see the first A.C. screen grid type of receiver introduced into New Yealand. This is the Atwater Kent .-Model 55, embodying two 224’s (A.C. sereen grid), two 227’s, and two 245’s. The screen grid valve as radio fre- _ quency amplifier, has enormous amplification, and to introduce tone the first audio stage is resistance coupled to the detector, which is of the Anodebend type. A moving coil loudspeaker ~

— of a special design goes with the set. The best results cannot be obtained.unless this combination is used. . The valves are shielded by aluminium cans, the condensers are ganged, and the dial calibrated in both kilocycles .and degrees. The set is put up in both a eabinet and Console models. This latter, model‘is finished in grained imitation wood. Each portion of the power pack. is efficiently shielded from its neighbour, so that interaction and hum are almost imperceptible. In fact, the receiver is so silent that, when it. is not on a station, it is difficult to know whether the set is turned on or not.- For this reason pilot lights are provided. Model 60 is yery similar, but is slightly different in its lay-out. Selectivity in these receivers is such that the former nrodel will cut out all but 2BL when operating on 1YA. With the Model 62, 1YA can be tuned out in favour of 2BL. (Stands Nos. and 14, ABEL, SMEETON, LIMITED. Somu three months ago the American radio world had its interest aroused by a terse sentence from the Crossley Radio Corporation. It read: "Wait for thé big news in radio-out July 21." And now the.same _ pronouncement is being made by the New Zealand distributors, Abel, Smeeton, Ltd. This time the date is October 30. The big news will be awaited with interest by all who have ‘had. any connection with the Crossley receivers, This very popular line has had many supporters throughout New Zealand, and the introduction of new and up-to- ‘@ oie

en date types (for. what else can this big news mean) will be awaited with keen expectation. Speculation is rife as to the technicalities of these new models, and it is more than likely that they will embody the A.C. screen grid, the 227 and the 245. Pore, When finally the new receivers were announced in. America, fast .aeroplanes were employed to carry the samples to the waiting dealers throughout. the country. Although these modern tactics cannot be employed in New Zealand, we are expecting a great throng round Abel, Smeeton’s stand to see the outcome of this big news. Stand No. 15. STEINITE AND ULTIMATE, RAL.10, LTD., have arranged for this stand demonstrations of both Steinite and Ultimate sets. The Ultimate is a small A.C. receiver designed b; the engineers of this firm to cover both short-wave and broadeast band. There are four ,valves, including onestage of A.C. secreen-grid. In spite of the fact that by.altering the plug-in coils, both broadcast and short-wave bands may be covered, only one tuning control is employed. The cabinet finished in maroon is built up of heavy aluminium sheet, with three separately shielded compartments. The latest’ Ultimate product is a console model of the electric Ultimate housed in the most attractive low-boy cabinet, and incor-. porating a dynamic type of. loudspeaker. . The Steinite is a console type of receiver in two distinct styles. The more expensive with-two 250 valves in the last stage incorporates an elecseainstmmidamene

-- ---_- tric. gramophone. The smaller model with the new 245 type of valve in the last stage and 227’s in the other stages. The cabinet complies with the latest ideals of design. In addition to the two receivers, Arcturus valves and Samson power amplifiers will be displayed. Both are new to New Zealand, although they have earned a’ great reputation for themselves in America, The valves are characterised by blue glass. An outstanding. feature about the new Arcturu:s 227 is the rapidity with which the cathode heats, resulting in highest efficiency, humless operation, and audible reception within 7. to 10 ° seconds. These valves are. recommended for all A.C. sets, They are represented in all the main types of oY en valves. 3 The Samson power amplifier is in two styles. ‘They can be employed for use in either home, out-of-doors, or theatre. The smaller model employs the 210 valve, and the larger the 250. Stand No. 16. SELECTRA RADIO. N some ways this stand is unique, Whereas other exhibitors have on show radio receivers constructed outside New Zealand, Sélectra Radio are showing only New Zealand made products, and these compare very favourably with the imported article. The Selectra Junior A.C. Three, embodying two E415 valves and one B609, is a handy receiver for those who do noj wish to make a very big capital lay. This receiver, contained in..a neat little cabinet, is built up of the. very best components. It has two

Se ( tuning dials, and does not employ’ reaction. In the. combination class, Selectra Radio can offer a most interesting model. This in appearance is quite equal to the American receivers, and for tonal qualities would be hard to excel. It contains six valves, 226’s in radio and audio amplifiers, a 227 and a 245. An Bpoch dynamic speaker ensures perfect reproduction over a: very wide musical seale.’ Again two dials are employed. ‘The electric motor is built in the top of the cabinet, as is done with American receivers. \A Webster pick-up is used. As well as complete receivers, a few _ components .will be shown. A _ blue spot magnetic speaker, in a very handsame and unusual type of cabinet, will be displayed. The A.C. Six comprises 226’s, 227’s and a 171 as‘power valve. This model employs single-dial control, and is contained in a Console. Small coils in the radio circuits bring the set into line with the latest conceptions of set design. Stand No. 17. COSSOR RADIO PRODUCTS. _ [HH name Cossor has become very well-known in New Zealand during the last season. As agents for the North Island, Radio, Ltd., have arranged to have a very complete display of these products during the exhibition. The well-known Cossor Melody Maker in both kit set and assembled _form, will be on view. ‘The Cossor in its ‘short period in this country has created an excellent record, and many who have ‘ heard of it and have not yet seen it, will have an excellent opportunity in the exhibition. Among the components will be the Cossor audio-transformer. This small piece of apparatus may be fitted into any radio receiver with excellent results. It is finished in handsome crystalline, with the designations of the terminals clearly marked. Cossor valves of the new types will be on exhibit. Of these, there are three main divisions: 2, 4, and 6 volt, including high-frequency, detector, audifrequency, and power valves. In addition, there are the screen-grid and the pentode. It is announced that 4-volt heater type A.C. valves will soon be making their appearance on our market. These will be readily looked forward to by all who have had experience in any of the Cossor products. tand No. 18. AMALGAMATED WIRELESS (A’SIA.), LTD. A VERY comprehensive display of A.W.A. products will be on view at this stand. Outstanding among these will be the Marconi moving coil speakers and cones. The Marconi moving coil speaker has an entirely new system of double suspension. This assures perfectly parallel ‘movement: of the coil at all times, which gives exceptional freedom of motion and absolute freedom from side play. The edge of the cone is unrestricted but carries a light ring of felt which prevents circulation of air waves from one side of the diaphragm to the other. Another electro-dynamiec speaker is the RCA 106, Its operation requires no more power from the receiving set than an ordinary loudspeaker of the magnetic type. It is extremely sensitive, and at the same time is capable cand

of handling a great volume without either distortion or rattle. The cabinet is highly original, yet rich’ in its simplicity. It is ‘beautifully finished in walnut, and panels of embroidered _ toile enables it to. harmonise with any home furnishing. The. speaker operates directly from the alternating current. : For those who find it inconvenient to use a moving coil’ loudspeaker, the "ROA 103 has been developed. The artistic appearance of this speaker is as completely. satisfying. to the eye as its performance is to the ear, Every semblance of a mechanical device has been eliminated from the attachment. A beautiful tapestry medallion conceals the mechanism of the speaker, and completes the decorative design of the instrument. . Other interesting.. exhibits will be AC amplifiers embodying: the fameus UX245 specially built for the amplification of gramophone musie-when a pickup is employed. There will be also 2 valve AC amplifiers with rectifiers for adding to a crystal set. ‘ Stand No. 19. SPEDDING, LTD. QN this stand will be seen four main groups of items of interest: Magnavox X-core dynamic speakers, Burgess radio batteries, Mullard valves, speakers, and transformers, Webster gramophone pick-ups. and amplifiers. The exhibit of Magnavox X-core dynamic speakers include all the latest models, together with several news and very tasteful cabinets. To all radio enthusiasts this exhibit. will be of .particular interest. The Burgess battery display will have.several items of particular interest, including one in which the construction of the radio battery is clearly shown. In this connection it is of particular interest to note the massive construction of the individual cells which go to form the famous Bur- | gess super-batteries. Mullard valves and speakers will be well portrayed, and a special feature of interest, in this direction is an exhibit of the complete process of manufacture of a ‘Mullard radio valve. This will be exceedingly attractive to all radio enthusiasts who will find the progressive construction of these all-British valves to be extremely interesting. A very interesting exhibit showing: the extreme sensitivity of the Webster amplifiers and their enormous amplifying eapacity will be shown, © and: will undoubtedly prove attractive and instructive to all who visit this stand. Demonstrations of a practical ‘nature, one, in particular being very fascinating, will be made on this stand, and altogether it is certain to be well supported by the visitors to the. Radio Bxhibition. Stand No. 20. FARMERS’ TRADING CO. HIS stand will be featured t¥ a very complete exhibition of A.W.A. products. These will include the latest developments in complete allelectric sets. Radiola 338 employs a pérfectlybalanced RCA, tuned radio frequency circuit consisting of three stages of radio frequency, detector and two stages of audio amplification. The design is somewhat different from the conventional. Model 44 Radiola represents’ the modern trend in radio receivers, It includes the new AC screen grid ‘radiotrons, and*the new power valve UX

ton aamenees 245. The novel stencil cut. station géelector dial and single tuning volume control are’ additional features whici: are both unusual and efficient. Model 46 is of the Highboy Console type, aud unusually attractive. It has singie dial control, and this operates the tuning, so that on the whole receiver theie is one inconspicuous knob. UX 244’s (screen grid) and 245 characterise the circuit. Added to its. many features is a built-in electro dyaumic speaker. ee ‘ A line distinctive to these manutacturers is the RCA _ superheterodyne. Right powerful AC radiotron valves are employed with a result that it is able to separate broadcasting stations with knife-edge selectivity without excluding any of the musical frequencies that are so necessary to faithtul reproduction. The circuit. consists: of two stages of tuned radio frequency, detector, two stages of tuned intermediate frequency, a second power -detector, and an audio amplifier. ; The Farmers’ Trading Co. wiil also be showing A.W.A. Duoforte, AWA Radiola Electric seven and other weilknown AWA products. In addition there will be other AWA products, ‘including loudspeakers and valves. Stand No. 21. JOHNS, LTD. At their stand, Johns, Ltd., are catering very extensively for the amateur constructor, especially the one who wishes to convert his set from DC to AC. Outstanding among the items will be the Westinghouse products, which include the very well-known metallic rectifiers, a series of which can be used ‘for A, B and © eliminators, The A unit is one that should appeal to those who do not wish to go to the trouble of re-wiring their sets, but who would rather use-an A eliminator. This rectifier is capable of supplying .ample eurrent for almost any set. In addition to these rectifiers. there will be complete chargers of both types, complete shiélding devices and other well-known products.

ames ‘ Complete séts will include the Ham-‘marlund-Roberts, a set which has justly earned a wide reputation throughout the country. ‘This exhibit will be of particular interest to those who are unable to instal an AC receiver, for nothing could.be more efii-. cient in the battery models than one of these regeneration-using sets.’ The AC user will be catered for by a small three-valve set designed and made by the exhibitors.’ This, like the Hammar-lund-Roberts, ‘is very efficient. From the cabinets: to the coils everything is made and assembled in New Zealand, with the obvious exceptions of such components. aS condensers, valve "sockets, valves, etc. ~~ Stand No. 22.: "NEW ZEALAND RADIO." PARTICULARS of the activity of this journal are not yet available. No doubt they will be exhibiting the ‘prize-winners of the set-building com.petition.. Details yill appear when to hand.