Radio IN THE HOME

Timaru Herald, Volume CXXV, Issue 17756, 17 September 1927, Page 11

Radio IN THE HOME

THE WEEKLY REVIEW.

During the week 21'C, 3LO, PGJJ, 2XAG, WLW and WGY, were Heard oil short waves. -Don’t • WLW wilL broadcast the Big I'ight on the 22nd inst. on 50 metres. 1 believe 2XAI) or 2XAU will also attempt the broadcast. 2NM was not heaid m -J'imaru as far as I can gather. this station commenced a transmission at 6.15 a.in. London time, but aitei a ten announcements, broke down, it is to be hoped that 2NM, will be on the air again soon. Even, it 2NM had continued to broadcast, it would have ticeu impossib'o to receive same ill J innu u. The question is, what- station transmitted morse irotn 5 p.m. till alter o p.m. on 2NM’s wavelength? The vvnter could not catch the call -sign and the greater part of the morse was too last. J understand that this station was not heard in Dunedin. Can a|y reader enlighten me? On the higher wavelengths there i> still too . much interference trom Joca. high frequency apparatus. More anon about this.

ON YOUR WAVELENGTH. < Several amateurs report poor reception lately. 1 quite agree with them, reception has not been wonderful, ami neituer have the . programmes. the writer listened to part of a transmission from 3YA last Saturday evening, it was Dave von noticed the repitition of ,t*mi< from all stations? One gets led up of hearing the same pieces over ami over again, perhaps the new direetoi of progiammos wi'l alter the present svstem. '•Listener in” agrees with tlie referees in Christchurch in tnidnig taulc with the broadcaster, whom thev sav criticises- their rulings and winds more the listeners don't want to hear it. Did von hear the announcer at the Wei lin Ldo n v. Canterbury match say, that a player had taken an “antiseptic" , 1 Well. 2YA is not a success, the daylight transmission 'hasn’t come up to expectations, the volume is not as promised and the modulation is on y fair Personally I can find no excuse ior the failure. Wc were promised “The most wonderful station, well you’re got it? the promises are hko the 'citv of its location, windy. i crimps the future holds improvement, we rarnestlv hope so. . Timaru is sti’l accommodating a howler cr two, evidently they have hides like ail ass. Amateurs still complain about local mterleroncc, violet ravs blue ravs, etc., etc. Perhaps the Government will spend a portion o. the £6OOll it collects from the listeners in for administration purposes, on ruminating “man made intoretorenee. “Again, perhaps, they might when it get: near election time. - ’ , Jt is gratifving to see that at least one Englishman' is ambitious enough to broaden'd on short waves irom Bli.-htv Mr Gerald Marcuse, the gentleman in question, deserves old bruises. ;;nd won d you btdu'vt' it, ho met with solid opposition ir-om flic B 15. C. in London. The B.l!.( . said u (oiildii't be done, although PC'Jd was doiim- it. Congratu’atioiis Mr Marcuse, vou have succeeded so far ill a wonderful maimer. 'Don’t you flunk that it was pathetic lor the authorities in England to request the Dutch station to h-oadcast the Empire Day celebrationfrom London. The request was turned down ami quite right too. /What pos;.ib'e excuse had the author.ties to ask a foreign, station to broadcast a programme of that character to our own Empire, when it was lack ol enteipiise and' ambition on the part ot the 8.8. C.

TRANSFORMER RATIOS. In the maioritv ol' eases it is ((uite safe te sav that transformers lor amlmIrcqucucv amplification are not selected for tin? eonciuions under winch tiny atto operate. Generally speaking, t.ie inttuencine: factors in the final choice ot an instrument are an arresting artyeitisemenl. good appearance, attractive. I : rice, or the. fact that so-and-so has one like it and says that n is 'civ we consider the important part piave.d bv.this instrmnent. and remember that upon its eihciey depends to a larec extent the success ol any set using iw'iik low-1 requeucy ampiilieation, it M 'em- -di ange that there is not a more general knowledge of the reqmrentenls of a transfarmer lor iumtmmng > certain set. It, is true that nianutatturers do not state ; 1 the useiul da concerning, their products, but I'oie there a greater demand lor this inioinitition it. won d probably be lorUicommg, and amateurs could then proceed to <■ esi'an their sets more intelligently .. n with a greater degree oi certainty that thev. would be doing the ng.it tiling . the' given circumstances. From tiie point - of view of offectm operation it is: essential that the impedance (thh resistance ottered to the applied fluctuating impulses) ol t;ic primary winding of an audic-i c(luenev transformer slial 1 be gu.ae than ’the.!plate to tiUiment nnpedamx of the preceding valve, both ttn,..e values being taken under working conditions. On the other band, the vfheienev of the transformer (using th ; term it its true scientific sense mi) I>ing absence of losmss) _demands a km pr.mary impedance, here hum t two conflicting desiderata.

The Question of Ratio. Tt r.iav be said that little is to be gained bv making the pnnuuv imp<dunce men' than three tunes that ot the vulva. Jf the latter vane » 1 fill, this means that the prnnan a 11 lnu v n large number ot turns >o«, transformer ratio is determined bv ,1m value of number of turns on secondarv (-T2l to the number 01. tu,s on primary ( —l' l )■ d is seen t at foi a. herh-impedanee valve, a liigh-iatio 1 ram-former would necessarily have a verv large number ot turns in t o .secondary, making the lll3tiul^. 1 b’lllvV and ’ expensive. besides this, •the eapacitv of the secondary would bo hhdier t'.an for one with iewer turtisT It thus appears advantageous to Use a low-ratio transformer having a nrimarv winding ol high impedance, in the ease of a low impedance power ra’vo it")- permissible to cmp.oy a higher n-'w trauslcrmer. since the piniimy impedance, and, therefore, the number of primary turns, is low, ana T2 the ratio -may be increased without

• T.l using too. much wire in the secondary The plate to filament impedance ot the valve preceding a transformei may, have a'valve ranging from 40 000 ohms for a. detector or L.I • to 60Ut ohms for a power valve. It is enviously impossible for any one t < - former to operate cfhc.eut y ovei th entire range, and yet that ;is wha is expected of it whon.it is bought without anv regard being had to th valvo impedance.

Special Transformers. Some manufacturers produce trapsors specially designed for airter-

(By “Listener In.”)

SLO.

ent stages of low-frequency amplification. This is good practice worthy of support, and increases the advantages of using special purposes valves in their correct places. It is not improbable that general purpose valves and transforms!® will dwindle in popularity, giving place to special components designed to operate together in their allotted stages. Why Not Publish Data? Meanwhile it would be a great improvement if tho impedances of audiotransformers were made known to the buying public iu the same way as are the impedances of valves. Until this desirable state is reached it would appear, from the foregoing considerations. advisable to keep to low ratio transformers such as 1-2, or 1-3, except in the last stage where, if a power, valve is employed, a higher ratio is permissible.

A lamp inscribed with a figure and two cabalistic letters is the only “electric" that lianas over the front door. A lift takes the spectator to the auditorium. .Nobody minds if you go behind the scenes! The scene-shifter is a quit.e efficient-looking mechanician who turns switches in a wordless hush. Oa, another floor is the stage. It consists of a polished dance-floor, draped withi flags and decorations and set about with, comfortable settees. llic stage manager sits at a central table surrounded bv more switches. Ho is, significantly, an old actor with seven years’ service at Drnry-lanc and 26 with J.C.W. to his credit—a venr ago he was managing for Boueicault. There is a grand piano in a corner and an orchestra in another. Although the room is empty except for the'stage manager and an old negro, the orchestra puts colour-ed-paper caps on its head, assumes an air of determined jollity and prepares for strenuous business. The stage manager turns a switch, and, smiling ingratiatingly at a small disc, remarks in’the beautifully dramatic accents ot the 'estimate theatre, “3LO speaking. 3LO Melodv Masters will now play ‘My Girl Has Eve Trouble and Can’t Se® M t , ' ” Whereupon the conductor springs to attention the jazz tune begins ( this "Showman has it on official guarantee). in dance-halls at Sorrento and Mordialloc, bush schools of art m Queens’and, on ships’ decks 5000 miles a\vay, on bungalow verandahs in the Solomons and even in European houses in Japan, couples clasp each other and proceed to walk around. The music thumps to an end. There is a solitary encore, it arrives by ’phone from Albert Park and is at once acceded to. Anon an elderly negro gets up, smiling and bowing, waddles towards another disc mounted on a single e.cgant) Jacobean leg. and proceeds to sing “Hawaiian Kisses" to it. i here is something pathetic about this old ne"To. Time was when lie cut his dro-Il capers and contorted his humorous black face m a hundred music-hall®, witli the romantic glare of ’lie spotught upon him and intoxcal mg roars at laughter in his cars. Xmv lie ro Is hid glistening eyes, Hashes lus white teeth} vtos f li ' lvw-S. SilOots CUIISE* shakes a finger' at ail imaginary crying babv and raps out a retort to aiu-hlJ* ions' in I •’l'jeetor in a perspiring efiort W overcome the limitations of electricity and place himself before the biggest audience lie has even known. Only fl, sol'l'irv ehuek'e and the moumtit clapping of the stage manager accompanies him back to his seat. lint 31,0. which is progressive, read? this deficionev in its equipment. If. aims at making the entertainment as like, flesh and blood as science ttiil permit. The old-fashioned studio like a padded ceT has gone. Ihe modem studio has become gay, bustling and even noisv. The room begins to nU.

Couples jazz m omson with the coupes scattered about the starry night Md;-. A lady in sequins is spurred to t're<ii aseeuts in song !>V applause which she can hear and which the hsten-ers-m can hear as well. Ihc; stage manager does not object it the scrap j tur „f a chair leg or an unrenearsed lover’s sigh gets mixed up m the programme and wanders to Dogs Ha*. Kvervtliing must be done to make JJoj 3 Flat'think that it is not at homel'or, murmur the radio enthusiasts, gns « Fie onlv theatre ot the lutme—t a tii eat re of Shakespeare and the Dolly Sifters is doomed. Between the vocal items the stage manager sends out communications from the police., \MU a,iv listener who knows the whereabouts of'Jane Smith ask her. to come to tha Dash Hospital at one. matter very uigent The jazz breaks out again, the couples clasp, but a lamt shadow ot tragedy seems to hang abouMhe room. Among the hosts of persons who write to" radio stations praising oi db :.,...tii»r to the programme aie >lll sorts and varieties of listeners. Some pen ilic',lifted epistles on expensive paper, n'fa v, tear a .sheet ot mmepapei and a i- to scribble with a burnt stick. iSome spell as we’l as a dictionary,

11 But liero is how one man in iNew Zealand writes to 2J3L, Sydney:— 'have' much pleasur in writing a few lines to you on the transmit-ion nf Statmn 2BL. I am very please to say’ I have better rceeiptions from your station chan 1 have from. ain. o^ OUW.^LMQCb plaim but 1 2BL 1 i^Ki. iVbove'them all of q o'clock each night as if it u-ers onlv half a mile r.wav The which was very good. Many hanks to the past. Wishing your nation 2BL all success in the futchor.—Yours truly,. .