RADIO

Star (Christchurch), Volume XLIV, Issue 145, 20 June 1931, Page 23 (Supplement)

RADIO

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"AERIAL.")

A MILLIAMMETER AS A DETECTOR OF TROUBLES,

A Useful Method. “ Did you ever think of using a milliammeter as a detector of valve troubles in a wireless :sct? In some ways it is MUit© a useful method, as the readings of the plat© current above, below and equal to normal, give definite indications. in conjunction with other symptoms, of the source of almost any trouble in the wireless set,” says a radio Unfortunately for the novice, there is a catch in this, as the normal reading is not usually known in such cases and the actual emission of any valve may differ somewhat from that shown on the leaflet the manufacturer usually inserts in a valve carton showing its curves. The question is: What percentage of the plate current can be assumed to be normal for practical purposes? Not An Easy Question. This is by no means an easy question to answer, for a variety of reasons, and it involves some points of wide practical interest. In the first place it must be remembered" that, in the receiving set, the plate voltage is never equal to that of the “B ” positive tapping which serves a particular valve, for there is always some direct current resistance in the plate circuit. This may be due to the primary windings of a transformer, to a choke, or to the plate resistance of a resistance-capacity coupled circuit. In any case a voltage drop takes place across the resistance, and its presence has the effect of altering somewhat the shape of the grid-volts—plate-current characteristic. The actual plate voltage is easily discovered with the help of the milliammeter. If. for example, the battery voltage is 100, the transformer primary has a resistance of, say, 5000 ohms, and 2 milliamperes of current are found to be flowing, the plate voltage can be worked out by Ohm’s Law. We have first to find the voltage dropped across the transformer primary. Multiplying 5000 (Ii in ohms) by 0.002 (C in amperes), we obtain 10 (E in volts). Ten subtracted from 300 leaves 90, which is the plate voltage. To Find the Resistance Value.

If not already known, the D.C. resistance of the component providing the plate circuit impedance is easily found with the milliammeter. To do so use, to begin with at any rate, a very low tapping—say, G volts—of the “B ” battery, or, if there is no such tapping, disconnect the “ B ” battery and connect the “A ” battery, or the grid battery, in its place. Remove all the valves, and connect the milliammeter between the negative filament socket and the plate socket of the appropriate valve-holder. Note carefully the reading indicated. Suppose that the voltage is 6, and that the reading is 5 milliamperes, a transformer primary being under test. By Ohm’s Law the resistance of the windings is 6 divided by o.oos—namely, 1200 ohms. If a very low reading is obtained with a voltage of 6, increase the voltage until a current flow of at least one milliampere is indicated. In order to arrive at the normal plate current for any set, the D.C. resistance in the plate circuit must be taken into consideration and the actual plate voltage of each valve should be found, preferably by actual measurement, or, if time does not permit of this, by careful estimation. The grid bias, if any, being known, it is then a simple matter to find the normal plate current from makers’ curves. Any valve which fails to show at least 75 to 80 per cent of the rated current may be regarded as having lost so much of its emission that it is of no great use in the wireless receiving set. Schedule of 2ZW.

The following is reprinted from this week’s “Radio Record”:—

Station 2ZW, Wellington, operating on 269.9 m. (1120k.c.), notifies u s of its schedule, which is as under:— Sunday—lo to 10.30 a,m., news and music; 11 a.m., devotional service; 8 p.m. (approx.) to 10 p.m.. concert. Monday and Tuesjday—lo to 11.30 a.m., special session for womenfolk; 12 noon to 2 Rm., news and miscellaneous programme; 7 to 8 p.m., dinner hour music; 8 to 10 p.m., concert programme; 10 to 11 p.m., dance music. Wednesday—Similar to Tuesday, with the addition of a children’s programme at 5 p.m. Thursday—Similar to Tuesday.

Friday—lo to 11.30 a.m., special session for womenfolk; 12 noon to 2 p.m., news and miscellaneous programme. Saturday—2.3o to 5 p’.m., miscellaneous music; 7 to 8 p.m., dinner music; 8 to 10.30 p.m.. concert programme; 10.30 to 12 midnight, dance music.

Sunday evening concert programme will commence immediately after the conclusion of 2YA’s church service ser-

WEEK-END PROGRAMMES.

FOR TO-NIGHT. 2YA, Wellington. 7.0: News session. 8.0: “A Scottish Night Salon Orchestra, “ Highland Laddie” (Seredy). 8.8: Contralto —Mrs Ray Kemp, “Ye Banks and Braes ”, “Turn Ye to Me”. 8.14: Pipe selection—Piper Smith, “Scottish Medley ”. 8.IS: Tenor—Mr Will Hancock, “ Afton Water”, “Rowan Tree”. 8.24: Orchestra, “Coronach” (Barratt). 8.32: Soprano—Mrs G. Stark, “The Auld House”, “Coinin’ Thro’ the Rye”. 8.38: Saxophone—Rene Dumont and Band, “Nola”, " Saxophobia ”. 8.42: Quartet—The Etude, “Mary”. 8.46: Orchestra, “The Bluebells of Scotland”. 8.54: Baritone —Mr G. Stark, “ Blue Bonnets Over the Border ”, “ The Standard on the Braes o’ Mar”. 9.2: Weather report. 9.4: Piper Smith, “Scottish Medley”. 9.8: Baritone—Mr Ray Kemp, “ Bonnie Dundee ”, “ Bonnie Banks o’ Loch Lomond ”. 9.14: Orchestra* “Highland Laddie”. 9.22: Duet—Mr and Mrs G. Stark “O, Wert Thou in the Cauld Blast?”. 9.26: Debroy Somers Band, “ It’s a Lovely War”. ~9-34: Soprano—Miss Gretta Stark, Ma Heart is Sail”; “Robin Adair”. 9.40: Orchestra, “My Ain Folk”. 9.46: Quartet—The Etude, “Aye Waukin O”. 9.54: Orchestra, “Keltic Suite” (Foulds). 10.0: Dance programme: Foxtrots, “Una Gotita rle L .uvia” “With All My Heart”, “Running Between the Raindrops”. 10 9* Waltz, “Cortesana”. Blues, “JJiniatura 10.15: Vocal (in Spanish)—Pilar Arcos and Fausto Alvarez, “El Nido 10.1 s: Foxtrots—“ Melodias de Malambo , Hello, Beautiful!” 10.24: Waltzes, “ Flor de Ayote ”, “Heavenly Night”. 10.30: Foxtrot. “QueCalor ” Blues, “ Anhelos ”. 10.36: Vocal (in Spanish)—Pilar Arcos and Fausto Alvarez, “ Besos Maltidos ”. 10.39- Foxtrots. “ Something to Remember You By , Lorando Hasta Dormir ”, “ Body and Soul”. 10.48: Waltzes, “No Me Olvidaras”, “Tears”. 10.54: Foxtrots, Solo un Amante", “Damian” 110* Sporting summary. 11.10: Close". 3YA, Christchurch.

7.0: News session. 7.30: Sports results. S.O: Re-lay of programmo from 4YA. 10.0 (approx) : Dance music. Foxtrots, “ Tie a Little String ”, “ You Didn't”, “I Hate Myself”. 10.9- Waltz ‘‘Reaching for the Moon”. 10 12- Foxtrots, ‘‘Think a Little Kindlv of’ Me’”, "I’m So Afraid of You”. 20.1 - Vocal— Harry Richman, “ When Your Lover Has £2 ne 10 21: Foxtrots, ‘‘My Ideal”, I Surrender, Dear ”, “ To-morrow is Another Day.” 10.30: Waltzes, “Falling in Love,” “ The Waltz of the Hills.” 10.36: Foxtrots, “When You Were the Blossom”, “Walkin’ My Baby,” “ When the Bloom is on the Sage”. 10.45: Vocal—Harry Richman, “Just a Gigolo”. 10.45: Foxtrots “I Want You for Myself”, “To Make a Long Story Short ”, “ Liza Lee ”, •• Heartaches ”, Close. rOR SUNDAY. 2YA, Wellington (416m.—720k.) 3.0: Afternoon session. 6.0: Children’s song service. 7.0: St Andrew’s Presbyterian Church. Preacher: Rev R. j. Howie, B.A. 8.15 (approx.): Relay of Band Recital by the Wellington Municipol Tramways Band from St James’ Theatre. Close. 3YA, Christchurch (306m.—980k.) 3.0: Gramophone recital. 5.30- Children’s song service by children of Church of England Sunday schools 6 15Studio chimes. 6.30: Musical recordings. ..or Christchurch Anglican Cathedral. I Teacher: Rev o. Fitzgerald. 5.25 (approx): Selection—Studio Octet “ Overture to Norma” (Bellini). 8.31: TenorMr Finest Rogers, “Ah, Moon of jjv Delight”. Soprano, Madame Gower Burns, “ The Lord is My Light”, 5.39: Piano—Michael Zadora. “La Passion” “Prelude in C Major”. 8.45: Studio Octet, ‘Folk Tune and Fiddle Dance” (Fletcher). 8.54: Contralto—Miss Alie a Vinsen, “ A I-leap <pf Rose Leaves ”, , “ The Hills of Donegal”. 9.0- Weather forecast. 9.2: Studio .Octet, “La Traviata” (Verdi) 9.16: Orahd Opera Duo, ' Dear Love of Aline ”. Tenor—-Mr E* - -

Greetings”. 9.31: Studio String Quartet, “Scherzo” (Cherubini). 9.39: Miss Vinsen, “Abide With Me”. 9.43: Male choir—Don Cossacks, “ March Prince Cleg”. 9.47: Grand Opera Duo, “Stay! Stay! Turiddu ”. 9.53: Studio Octet, “ Monsieur Beaucaire ”. 9.56: Madame Gower Burns, “ Because of Thee ”, Mr Rogers. “Dear Sleeping Rose”. 10.1: St Hilda’s Professional Band, “Hallelujah Chorus ”. Close. 3ZC, Christchurch (250 m 10 to 11.30: Morning session. 6.0 p.m.: Dinner music. 7.0: Short-wave session (on 50 metres). 8.0: Evening concert session. “ Fireflies ” and “ Fluttering Dove”, Read Orchestra; “Cradle Song” Anna Case ((soprano); “La Paloma ” and “O Sole Mio ”, Monde (accordeon); “Punchinello”, Edmund Jahn (baritone); “ Orientale ” and “Chant Sana Paroles”, Albert Spalding (violin); “A non Credevi Tu ”, Guiseppe. Anselma (tenor); “ Invocation ”. Stellario Cambria (mandolin); “Romance” from “ L’Eclair ”, Kitty Berger (harp-zither); “Shepherd’s Love” and “A Kiss in the Dark ”, Claudio Muzio (soprano); “Dream of the Tyrolienne ”, Venetian Instrumental Quartet; “They All Love Jack” and “The Warrior’s Song”, Arthur Middleton (bass); Fantasia from “Norma”, flute and clarinet duet; “ Vesti al Guibba ”, Giovanni Zenatello (tenor); “ The Little Shepherd ” and “Arabesque in G Major”, Robert Schmitz (piano); “Carnival of Venice”, Alice Verlet (soprano) ; “ Wait Until the Roses Bloom ”, Wheeler Wadsworth (saxophone); “Credo” and “A Tanto Amor”, Mario Laurenti (baritone); i* Maritana ” overture, Sodero’s Band. 9.45: Close. FOR MONDAY. 2YA, Wellington (416 m 10.0: Gramophone recordings. 11.12: Lecturette, “Cooking.” 11.37: Lecturette, “Health Hints or First Aid.” 12.0: Lunch hour music. 2.0: Selected items. 3.30 and 4.30: Sporting results. 5.0: Children. 6.0: Dinner music; Orchestra, “ Pique Dame ” Overture. “ Polonaise No. 1 in A.” “ Dynamiden Waltz ” (Josef Strauss). “Hungarian Dances” Nos. 5 and 6. “ Myosotis Waltz ” (Waldteufel). “The Skaters” (Waldteufel). “La Danseuse.” “Ballet Egyptien.” ’Cello, “The Swan” (Saint Saens). “ The Merry Widow ” Selection. “Scherzo From Midsummer Night’s Dream ” (Mendelssohn).

7.0: News session. 7.40: Lecturette, Mr H. C. South, “ Books, Grave and Gay.” S.O: Overture, Concertgebou w Orchestra, “Anacreon.” 8.11: Baritone, Mr Eric Harrison, “ Wanderer’s Song.” 8.14: Musical Portrait Series, “ Schumann.” Mr Gordon Short (piano) and Mr W. Ilaydock (violin). Piano, Selection from “Carnival.” Piano and violin.

“ Second Movement ” from “ Sonata in D Minor.” 8.25: Soprano, Mrs Amy Woodward, “The Almond Tree”; “Moonlight”; “’Twas in the Lovely Month of May.” 8.33; Piano, Selection from “Fantasia”; piano and violin, Selection from “Sonata in A Minor.” 8.44: Contralto, Mrs Wilfred Andrews, “ The Ring Upon My Finger”; “The Green Hat”; “Melancholy.” 5.50: Trio, Casals, Cortot and Thibaud, “ Trio in D Minor.” 8.58: Duet, Mrs Woodward and Mrs Andrews, “ Icli Grolle Nicht ” (I’ll Not Repine). 9.2: Weather repoi't. 9.4: Madrid Symphony Orchestra, “Noche De Arabia.” 9.12: Baritone, Mr Eric Harrison, “Life and Death.” 9.16: Half-hour of “ Maritana ” with orchestral accompaniment (Wallace). Selection, 2YA Orchestrina, “Maritana” Overture. 9.26: Mrs Woodward, “’ Tis the Harp in the Air.” 9.30: Mrs Andrews,

“In Happy Moments.” 9.33: Duet, Mrs Woodward and Mrs Andrews, “ Sainted Mother.” 9.37: Mr Harrison, “There is a Flower That Bloometh.” 9.40: Mrs Woodward, “ Scenes That Are Brightest.” 9.43: Mrs Andrews, “Alas! Those Chimes.” 9.46: ’Cello, Pablo Casals,

“Spanish Dance” (Popper); “Vito.” 9.52: Orchestrina, “Pilgrims’ Chorus” (Wagner) ; March, “ Coronation March ” (Meyerbeer). 10.0: Dance music: Foxtrots, “Out of Breath”; “Sweet and Hot”; “I Am Only Human After All”; “Bye Bye Blues.” 10.12: Waltz, “Waiting For You.” Foxtrots, “ Hittin’ the Bottle”: “Highway to Heaven.” 10.21: Vocal, Allen M’Quhae, “At the End of a Cobblestone Road.” 10.24; Foxtrots, “In Memory of You”; “Love Comes in the Moonlight”; “How Are You Tonight in Hawaii?” 10.33: Waltz, “Beneath Montana Skies.” Foxtrots, “ Miss Hannah”; “Here Comes the Sun.” 10.42: Vocal, Allen M’Quhae, “The Dawn Brought Me Love and You.” 10.45: Foxtrots, “If You’re Not Kissing Me”;

“ Sittin* on a Rainbow”; “Lo Lo.” 10.54: Foxtrots, “Out of a Clear Blue Sky”; “I’m Needin’ You.” 11.0: Close. 3YA, Christchurch (306m.—980k.).

3.0: Gramophone recital. 4.25: Sports results. 5.0: Children. 6.0: Dinner music:—Orchestra, “The Gipsy Baron” (Strauss). Trio, “ Pierette ” (Chaminade). Orchestra, “ Only a Rose.” “Eva” Medley. “ Spanish Dance No. 1.” “ The Perfect Song.” “ Frederick ” Medley (Debar). “ Spanish Serenade.” “ Sylvia ” (Speaks). Trio, “ Dalvisa ” (Sandby). Orchestra, “ Lehariana.”

7.0: News session. 7.30: Dialogue, Messrs E. E. Wiltshire and F. C. Fairclough, “ The Story of the Garden ” (continued). S.O: Band programme by the Christchurch Municipal Band and assisting 3YA artists: March, Band, “Jack o’ Lantern.” 8.6: Tenor, Mr J. Haydn Williams, “A Venetian Song”; "When In Your Eyes I Gaze.” 8.10: Organ, Leo Stin, “ Berceuse De Jocelyn” (Godard); “Le Petit Quinquin ” (Dessousseaux). 8.16: Contralto, Miss C. Freeman Brown, “When Rooks Fly Homeward"; “Oh, Thank Me Not.” 8.22: Band, “D’ye Ken John Peel?” 8.27: Songs at the piano, Mr Jack Blair, “Love Among the Millionaires”; “Rolling Down the River.” 8.33: Saxophone, Feith and Kleinafh, “Souvenir” (Zakrgevslcy) ; Rene Dumont “ Saxophobia ” (Wiedoeft). 8.39: Band, “The Elephants Parade” (De Basque). 5.45: Baritone, Mr K. Murray Fountain, “ The Roman Road”; “The Rose of Tralee.” Ssl: Band, "The Pirates of Penzance” (Sullivan). 9.3: Weather forecast. 9.5: Brunswick Salon Orchestra, “Fox Movietone Follies Medley.” 9.9: Mr Williams, “Three Songs of the Sea.” 9.15: Accordeon, Medard Ferrero, “ Czardas ” (Monti); “ Hungarian Dance No. 5” (Brahms). 9.21: Miss Brown, “A Song of Autumn.” 9.25: Band, “Ecstasy” (Baynes). 9.31: Mr Blair, “Harmony Heaven”: “When You Come to the End of the Day.” 9.37: Humour, Wish Wynne, “Blue Beard”; “An Embankment Impression.” 9.43: Mr Fountain, “Just For To-day”; “My Desert Rose.” 9.47: Cornet Duo, Bandsmen L. Bruce and E. Barber, “Jollification” Polka Band, “Changing Guard” (Ord Hume). 10.0: Close. 3ZC, Christchurch (250 m 10 a.m.: Women’s session: “Garland of Old-fashioned Roses,” Salon Orchestra. 10.5: Tested recipes. 10.25: “ Mountain Echoes,” Venetian Instrumental Quartet: “From the Land of the Sky-blue Water,” Frieda Hempel (soprano) ; “ Frasquita,” Carl Flescli (violin) ; “To-morrow Land,” waltz medley, Ernest L. Stevens (piano); “ Romanza del fiore,” Guido Ciccolini (tenor); “The Three Republics Grand March,” New York Military Band; “ Sweet Blue Bird,” Salon Orchestra; “Memories,” Venetian Instrumental Quartet; “Lullaby,” Frieda Hempel (soprano); “Paradise,” Carl Fleseh (violin); “Peruvian Triste,” Carlos Valderrama (piano); " Cortigiani,” Mario Laurenti (baritone) ; “ Dominion of Canada,” march, Sodero’s Band. 11.30: Close. 12 noon to 2.0 p.m.: News and luncheon music.