RADIO

Star (Christchurch), Issue 19197, 10 October 1930, Page 4

RADIO

(By

“AERIAL.”

NOTES AND NEWS. Screening. It does not appear to be generally known that screening in a screened-grid set, to be effective, must be thorough. In home-made screens it is most important that the lid should be almost airtight if maximum screening is desired, although a_ certain amount of screening is obtained even without the lid. Unless screens are earthed, or connected to filament negative, which amounts to the same thing, the screen has no definite potential except that induced in it by the interfering source. Fluctuations in this potential can therefor be passed on to the circuit outside. With a screen at filament potential at all points there should be no interference, as there will be no varying potential and no currents injit. 55 55 55 A Good Circuit. Having a Browning-Drake set on hand for redesigning, put it on the testing table last night. It was interesting to observe what tine results were obtained as a consequence of adhering strictly to the lay-out, specifications, capacities and values laid down in his pamphlet 'on the subject by Mr Browning. The ticklish portions were —as already mentioned several times in these- notes—those connected with (a) the correct capacity—.ool mfd. —of the fixed condenser across the primary of the first A.*F. transformer; (b) the proper value of grid leak—three megohms with, a Philips 615 valve its detector; (c) the right spacing of the two coils and their tuning condensers —eight inches, centre to centre; and (d) the care necessary in properly carrying out neutralisation. Tne valves in use are a UXI99 as R.F.; Philips 615 as detector, and two Philips 605 as audio amplifiers. The wiring having been proved to be correctly done—evidenced by signs of regeneration when the tickler was rotated (by the way, the tickler is turned anticlock for increase of regeneration)—the next step was neutralisation. There is only one way to do this:—Set the N.C. at about half capacity. Couple up aerial, earth and batteries; bring the set into resonance by adjusting the two tuning condensers to approximately the same setting; bring over the tickler and readjust the first condenser until a distinct double “ plop ” is audible in the speaker when the grid side of the second tuning condenser is touched with the moistened finger. Then turn the tickler forward (less reaction) until the double “plop” just disappears. Xow by touching the grid side of the second tuning condenser, moving the rotary plates of the first (aerial) tuning condenser and adjusting the neutraliser until no double “plops” are audible on any setting of the first tuning condenser, proper neutralisation will be effected. It is characteristic of the 3E?.-D. that the first tuning condenser’s setting is not at all critical during “ searching.” Stations come in at approximately their right dialling on the second (detector) tuning condenser, but when the first T.C. is brought to the light setting for the station tuned in on the second T.C., the increase in volume and gain, in selectivity are very great indeed. Using a small outdoor aerial—the nearer to 3YA one is with a 8.-D. in use the shorter must be the aerial—all the Australian “A ” and “ B ” class stations were reproduced at very fine volume indeed. It is not at all surprising that the 8.-D. is so popular with “ fans ” who are prepared to operate the set (if properly constructed) intelligently. By the way—again—it was found that 225 volts “B ” sufficed for the Philips 615; more than that caused a squeal. Also the UXI99 worked best on 675 volts “ B ” —as laid down by Mr Browning in his original specifications. Changes In 3ZC’s Schedule. Commencing as from Monday next, station 3ZC announces several alterations to their schedule of broadcasting hours. The midday session, which now closes at 1.30 p.m., will in future continue until 2 p.m., except on Tuesday, when the usual closing hour will be observed. In addition to the daily increase in hours, 3ZC will on Tuesday evenings go “on the air,” at 6.45 for the children’s session. From 6.15 an hour’s dinner music will be provided. The wireless and Morse session will commence at 7.15 and will continue until 7.45, to be followed by the news session. The station also announces a series of talks of interest which will be given each week in future.

TO-NIGHT’S CONCERTS. IYA, Auckland (332 Metrea). 3.0 to 4.30: Afternoon session. 5.0: Children. 6.0: Dinner music. 2YA, Wellington (416 Metres). 8.0: (Note. —During the course of this programme there will be a relay of a sound film feature from the Majestic Theatre). 2YA Orchestrina, “Morning, Noon and Night.” Soprano, Miss Dorothy Newman, “ The Amorous Goldfish.” Piano, Miss Mary Lennie, “Waltz in E Flat." (Chopin). Baritone, Mr Ernest Short, “ The Song of the Flea.” Orchestrina, “ La Boheme.” Elocution, Mr W. J. Mount joy, jun., “Home, Sweet Home.” 'Cello, Lauri Kennedy, “ Hungarian Rhapsody.” Contralto, Miss Jessie Shmith, “Angels Guard Thee,” “ The Swan.” Tenor, Mr Charles P. Edwards, “ Where’er You Walk.” Orchestrina, “ The Fortune Teller.” Weather report. Miss Newman, “ It’s No Use Crying for the Moon.” Trio, Fritz Kreisler, Hugo Kreisler and Michael Raucheisen, “ Arlesienne Intermezzo.” Mr Short, “Matilda,” “ Henry King.” Orchestrina, “ The Blue Danube.” Mr Mountjoy, “ The Road to Tringamoot.” ’’Cello, Lauri Kennedy, “ Cradle Song,” “ Songs My Mother Taught Me.” Miss Shmith, “ Obstination,” “ Secrecy.” Trio. Fritz Kreisler, Hugo Kreisler and Michael Raucheisen, “ Sanc.tissima.” Mr Edwards, “ Rose lyia-rie.” Orchestrina, “ Pizzicato Polka.” Close. 3YA, Christchurch. (306 Metres). 7.0: News session. 8.0: New Mayfair Orchestra, “Love Lies.” 5.4: Bass, Mr E. J. Johnson, “ The Song of Elybrias the Cretan,” “ Prince Ivan’s Song.” 8.11: Accordeon, Mrs E. Cosgrove, “Invercargill” (march), “E Pare Ra ” (waltz). 8.16: Valencia Quartet, “Ever of Thee.” 8.19: Studio Octet, “Pique Dame.” 8.26: Mezzosoprano, Miss Lucy Fullwood, “ Cupid, Fickle Cupid,” “Heigh Ho!” 8.31: Studio Octet, “ Melodie,” “Vanity.” 5.41:. Valencia Duo, “Somewhere a Voice is Calling.” 8.44: Mrs Cosgrove, “ Pickin’ Petals Off of Daisies,” “ Silver Threads Among the Gold.” 5.50: Tenor, Mr T. G. Rogers, “ The Barefoot Trail,” “Roses of Picardy.” 8.55: Studio Octet, “Welsh Selections.” 9.0: Weather forecast. 9.2: Valencia Quartet, “Sleep Gentle Lady.” 9.7: Contralto, Miss Mary Taylor, “Hu sheen,” “ Spring Goes A-Roaming.” 9.17: Studio Octet, “ Rosaura," “ Coquette,” “ Spanish Serenade.” 9.30: Dance music. Foxtrots, “ Sweetheart of All My Dreams,” “ Dance of the Paper Dolls,” “ Deep Night,” “ The Toyraaker’s Dream.” 9.42: Waltzes, "My Song of the Nile,” “ I’ll Always Be in Love With You.” Foxtrots, “ Turn on the Heat,” “ This is Heaven,” “If I Had a Talking Picture of You.” Vocal, G. H. Elliott, “Muddlin’ Thro’.” 10.0: Foxtrots, “ Little Pal,” “ Laughing Marionette,” “ Why Can’t You?” Waltzes, “ Sometimes,” “ Let Me Dream in Your Arms Again.” 10.15: Vocal, Stanley Kirkby, “ My Mother’s Eyes.” Foxtrots, “ Painting the Clouds With Sunshine,” “ Mean to Me,” “ Tiptoe Thro* the Tulips With Me,” '“ A Precious Little Thing Called Love.” 10.30: Waltz, “Lady Divine.” Foxtrot, “ Why Do I Love You?” Twostep, “ Mayorqua.” Vocal, G. U. Elliott, “Yodelling Coon.” 10.42: Foxtrots, " I’ve Never Seen a Smile Like Yours,” “I Think of What You Used to Think of Me,” “ Ol* Man River,” “ I Don't Know Why I Do It,” “Do Something.” Dutch dance, “ Eafle.” 11.0: Close. 3ZC, Christchurch (50 Metres). 7.0 to 8.30: Evening concert session on short wave. 4YA, Dunedin (461 Metres). 7.0: News. 8.0: National Symphony Orchestra, “Orpheus in Hades.” 8.9: Soprano, Miss A. Finnerty, “ A Toast to Love.” 8.13: Mixed chorus, “Sea Songs.” 8.17: Recital, Miss T. Northey, “A Charlady’s Confidences,” “A Shivvy Sauce.” 8.23: 4YA Trio, “Allegro Moderato ” (Reissiger). 8.32: Baritone, Mr N. Gamble, “ Faith in Spring,” “ Courage.” 8.38: Piano, Mr Max Scherek, “Carnival Jest.” 8.44: Contralto, Miss Helen Roy, “ String of Pearls.” 8.48: 4YA Trio, “Spanish Dance,” “Hungarian Dance.” 8.57: Tenor, Mr J. B. Hamilton, “ Boat Song.” 9.1: Weather report. 9.3: Royal Opera Orchestra, “ Sylvia Ballet—Pizzicato and Procession of Bacchus.” 9.11: Miss Finnerty, “ Brown Bird Singing,” “ You Brought Ireland to Me.” 9.18: Organ, Herbert Walton, “Death of Ase.” 9.22: Miss Northey, “Nini, Ninette, Ninon,” 9.26: Mr Gamble, “The Signpost.” 9.29: 4YA Trio, “ Minuet in F ” (Schubert), “Norwegian Dance.” 9.42: Miss Roy, “ Beloved, I Shall Wait,” “ The Garden Where My Soul Was Born.” 9.48: 'Cello, Mr P. J. Palmer, “Harlequinade.” 9.54: Mr Hamilton, “In Late September,” “Goodnight, Pretty Stars.” 9.59: New York Symphony Orchestra, ''Entrance of the Little Fauns.” 10.3: Close.