WIRELESS NEWS

Press, Volume LXVIII, Issue 20630, 20 August 1932, Page 8

WIRELESS NEWS

(By "MAX.")

It is pleasing to note that at least one club is' energetic enough to commence action relative to interference. The DX Club has sent invitations to dealers and societies whose interests are affected, and a meeting is called for next Wednesday evening at the rooms of the Radio Society of Christchurch, Inc. This is the right spirit, and it is hoped that every success will follow this endeavour to rectify a most serious problem. Mr A. Webster, a vice-president of the newly-formed New Zealand Radio Institute, was in Christchurch last week combining business with _ pleasure. Whilst here he was interviewing dealers with the object of forming a branch of the institute locally. There are three classes of members, full _ members, associate members, and juniors, the lirstnamcd being qualified servicemen. The question as to whether hcensed wiremen, who are exempted from sitting .or the examination for servicemen, shall be admitted as full members will probably Je overcome by offering such members the opportunity to sit for a radio cx amination sot by the institute long, using the same wave-len a th. m. . "Rmoklvn Technical High School , IMO-Stt transmitter, which is owns a 101 4-v.ot belonging to the a duplicate of A r t he call of WNYC. municipality " but r h "'°J''.he 0 «" T tho on© at tnc scih - . rmrcty j for instructional re-brondc^tr, cipal a FP ar ! l rqnf ; rn it.ter on a boat matter from n tr. - i iar t 10 ur. Items which is used "J f sufficient interest considered to are put on by. the J no*«:m- ■ Q f a might be de.rnpt ve "fthejrn fl boat Qonitore Marconi is stated to have performed most successful transmission ' nltri short waves covering a disit'toonS the capacities and ind ,,rtan '^°| { - elements of the valve offer c ' ltbcu ' t ' o ®' However, these can be made to perfori the functions themselves bv P very high positive potential upon the 3 and sometimes a negative voltage upon the anode.. Electrons shoot back and forth through the grid meshes, a small number actually striking the electrode and flowing as grid current but the great majority swing or osculate through the grid, accelerating towards it and then being pulled up to start a fresh half evelo, and so on. The time taken to travel backwards and forwards determines the frequency and is controlled by the grid and plate potentials. A high negative plate voltage, for example, would shorten tho time taken for the electrons to slow down each time they passed through tho grid meshes towards tho anode. In the tests mentioned above a beam controlled by reflectors was employed by tho Marches©.

"Radio News'' describes a short wavo superliefc for tho ultra short wavelengths in tho vicinity of five metres. ITp to the present timo it has been found that a- super-regenerative receiver using two valves has given best results. This superhet requires a first detector of the regenerative type, an oscillator to supplv tho beat frequency for the intermediate amplifiers, of which there arp two, a second detector with a second oscillator, and a pushpull audio stage. Altogether six valves are required r/nd the results should bo of the best. With the super-regenera-tive two tube outfit, only one valve actually dfies the work, the other simply putting negative impulses upon the grid at regular super-radio frequencies to prevent the detector from breaking into oscillation. It therefore operates just below this point without danger of spilling over. * •» The-type 'B2 rectifier is a big improvement over the ordinary 280 and 281 in many ways. It is a mercury vapour valve and takes 2J volts upon the filament and three amps. The drop in volts is steady at fifteen on the plate and this is where there is a decided gain. The maximum voltage that should be applied is 500 R.M.S. value. Care is necessary with the filter, as large condensers on the input side are likely to build up the voltage to four times tho actual E.M.B. value. A choke is therefore indicated next the input. The rectified output is 125 milliamps, and the 1 inverse or breakdown voltage is 1400. *■ * Wireless telegraphy classes for the signallers recommence next month. Last year the. members-of the unit were concentrating in visual work, but now that they have passed the required tests for this branch instruction will bo given in wireless telegraphy. This does not mean that wholo time will be devoted to wireless telegraphy, but that one section will be doing this work each parade night. The scheme will include field work with portable outfits. « # "QST" gives particulars of earth systems employing pipes driven into the ground in lieu of an indifferent water pipe. It shows that a diameter exceeding one inch is not required, but that the length of the pipe in the soil counts for a great deal. This pipe must go down to" the moisture level, eight feet being about correct. If one rod gave a certain resistance then increasing the number shows that with a separation of four feet two rods gave a resistance about 30 per cent, lower, whilst three pipes lowered the resistance over fifty per cent, and a fourth rod reduced the losses about 60 per cent. Separating the pipes ten feet gave slightly better results, but not very much, not more than ten per cent. Another aid to securing good earth is to dig a trench around the pipe or pipes and place chemicals in the trench. Magnesium sulphate, common rock fait, and sulphate of coper are often chosen to lower tho resistance of the ground. Water is poured upon the part after tlie soil is filled in again. A thorough treatment in this manner will be effective for two or three' years, occasional watering being necessary in the dry weather. « " ■* Matters in the Radio Society of Christchurch arc now well on the way to ensure smooth working. Last Thursday showed renewed enthusiasm. With a programme arranged to fill in the evenings until the end of September, members should find plenty to keep their attention. Another talk by Mr R. J. Gibbs on air force radio will bo given shortly. Ono night will be devoted to a "competition to discover a fault placed in a. receiver and a prize

Notes From Far and Near

BROADCASTING. TO-DAY'S PROGRAMMES. 3YA, CHRIST CHURCH (930 Kilocycles.) 3 p.m.: Selected recordings. 4.30: Sports results. 5.0: Children, by Aunt Pat. 6.0. nim.c-r music 7.0: News and reports. 7.45: Town Planning Talk, A. H. Bridge "Amen., ties." 6.0: Concert programme. Clmstchurch Salon Orchestra (Conductor, Francis E. Bate), "A Comedy—Overture Partridge). 8.13: Kerordine lu tz tet, "Old Man Noah. S.lo. Kecorilint (Cornet) Sylvester Ahola, Absent (Metcalfe). 8.1S: Jazz songs, Bex Sayers "Im Happy When You're Happy 1 His Dog" (Pryor). 8.27: Sketches Naaro Hooper and Den ye Cow The Pariljng , (both by Garde loach). ( Jij%er ready "Sketches" are published by Messrs Samuel French Limited 26 «outhamp on Street, Strand, London, W.C.-.) 8.39. Salon Orchestra, Rhythmic _ Character Themes "Tho Philanderer ; The Hustler , Tho Flapper"; "The Show-off" (a by Sanders . S f>'>' Soprano, Kvehno Hill, Daffodils from My Garden" (Boanas); "The Little Brown Owl" (Sanderson). 8.57: Recording (Yodelling), Andreany, "Tyrolean Polka (Blangy) 9.0: Weather forecast and notices. 9.2: Reserved. 9.17: Jazz songs, Rex Sayers, "When You Were the Blossom of Buttercup Lane" (Meyer); "Home" (Van Steeden). 9.24: Recording, Band of H.M. Coldstream Guards, "A Musical Switch" (Alford). 9.32: Sketch, Naaro Hooper and Denyg Cow, "Wave Lengths" (Garde Peach). "Ever-ready Sketches" aro published by Samuel French Ltd., 26 Southhampton St., Strand, Loudou, W.C.2.) 9.'JB: Salon Orchestra, "Mon Coeur Est X'our Toi' (Silesu); "The Flight of the Bumblo Bee" (ltimsky-Korsakov). 9.47: Soprano, Eveline Hill, "Tho Little Old Garden" (Hewitt); "Sweet Lady Moll" (Phillips). 9.51: Recording, Beryl Nowcll, "The Sweetest Story Ever Told" (Stultz). 9.54: Recording, Carl Fenton and Male Quartet, "Song of the Vagabonds" (Friml). 9.56: Recording, Argyll Reel and Strathspey Band, "Crampian"; "Eight-some Reel" (Traditional). 10.0: Sports summary." 10.10: Dance music.

3ZC. (1200 Kilo.) I 5.30-0.15 p.m.: Children's session. G.ID--6.45: Dinner music. 6.45-7.15: Sportiug and general news. 7.15: Musical items, 8-10; Concert session. 10-11: Danco programme. 2YA, WELLINGTON (720 Kilocycles.) 2.45: Relay. Rugby Football, Athletic Park. 5.0: Children, by Aunt Molly and Uncle Jasper. 6.0: Dinner music. 7.0: News and reports. 7.30: W.E.A. Session, Dr. I. L. G. Sutheranld, "Maori and Pakcha —The Maori as He Wa«." 8.0: Concert programme. Relayed by 2ZD, Masterton. Overture, 2YA Concert Orchestra (Conductor, Leon de Mauny), "The Merry Wives of Windsor" (Nicolai). 8.8: Recording (Baritone), Norman Allin, "The Midshipraito" (Adams). 8.12: Novelty Vocal and Instrumental Trio, "Tho Bridges Trio, ''ln a Chinese Templo Garden" (Ketelbey) ; "Wanganui City" (Oray); "Nako te Whare"; "To Wairua" (both arr. Piripata). 8.25: Mezzo-contralto, Dorothy Bymonds, "Reaping" (Coningsby-Clarke); "Tho Flower Song" (Gounod). 8.31: Tho Orchestra, "Patieuce" Selectiop (Sullivan). 8.43: Recording (Humour), Wish Wynne, ''There's Always Something" (Wiloock); "A Cockney Girl at tho Cinema" (Wynne). 8.49: Tho Orchestra, "Selection of Old and New Melodies" (Finck). 9.0: Weathor report and notices. 9.2: Reserved. 9.15: Novelty Vocal and Instrumental Trio, The Bridges Trio, "Tho Mocking Bird" (arr. Bridges); "Rocky Mountain Lullaby" (King); "Tho Wedding of tho Rose" (Jesse!); "is Noho Noi" (Piripata). 9.80: Mezzo-contralto, Dorothy Symonds, "The Violet" (Mozart); "The Traction Engino" (Marchan*). £>.36: Valse, Tho Orchestra, "Les Sirens" (Waldteufol). 9.41: Recording (Humour), "Tho Happiness Boys, "Twisting tho Dials." 9.49: lntormezzo, The Orchestra, "Nails" (Delibes). March, "The Lord Mayor" (Byford). 10.0: Sporting summary. 10.10: Relay of Dunce Musie from the Adclplii Cabaret.

SUNDAY. 3TA, CHRISTCHUBCH. - P.m.: Gramophono recital. £>.3o: % Children's Song Service by Anglican Sunday Schools. 6.15: Musical chimes. 0.30: Relay. St. Mary's Church, Merivala. Preacher. Veu. Arch. P. B. Haggitt. Organist and Choir Conductor, Alfred Worsley. 7.45 (approx.): S'electod recordings. 8.15: Concert programme. Belay of programme from 4YA, Duuedin. 3ZC. (1-200 Kilo.) 10-.11.U0 u.ui.: Concert programme. 0.15-8: Dinner music. 8-U.50: Concert session. 2TA, WELLINGTON 'J. p.m.: Selected recordings. 6.0: Children's Song Service, conducted by Uncle George, assisted by Children's Choir from Taranaki street Methodist CburcJh. 7.0: Relay of Evening Service from St. Andrew's Presbyterian Church. Preacher : Rev. R. J. Howie, B.A. Organist and Choirmaster : Frank Thomas. <5.16 (approx.): Concert programme (relayed by 2ZD, Masterton). .Studio Concert by Wellington Municipal Tramways Band (Conductor, K. Franklin) and 2YA Artists. March, • Tho Band, "Ravenswood" (Kiramer). Overture, "The Pied Piper" (Ham). Quartettes, The Waiaca Ladies' Quartette, "Rose in the Bud" (Forstcr); "Fidelin" (Brahms). Concert Duo, Bandmaster Ss'tevenson and Bandsman King, "Ida and Dot" (Lousey). Soprano, Lalla Vondersloot, "Little Brown Nightingale" (Turner); "Blackbirds! How You •Sing io Mo" (Turner). Recording (Vocal Duets), Herbert 1 Thorpe and Poster Richardson, (a) "Changing of the Guard" (Jetsam); (b) "TJ»o Hero and the Villain" (Bowen). Selection, Tho Band, "Euryanthe" (Weber). Weather report and notices. Duets, Mollie Fenton aud Nora Gray, (a) "Tho Greenwood Shado" (Sargeant); (b) "Jack and Jill" (Sanderson). Waltz, The Band, "Golden Grain" (Tussell). Contralto, Mrs P. Ramsey, (a) "Deep River" (Burleigh); (b) "Waiata Maori" (Hill). Recording (Male Quintet), "The Singing Sophomores, (a) "Hit the Deck," Medley (Youmans); (b) "Hollywood' Rose" (liohn). Intermezzo, The Band, "Aerial" (Ord Hume). The Waiata Ladies' Trio, "Neapolitan Nights" (Zamecnik). The Waiata Ladies' Quartet, "A Little Love, a Littlo Kiss" (Silesu). Intermezzo, The Band, "In Old Tibbet" (Gatty-Sellars). March, "El Abanico" (Javaloyes).

will be given to the winner, win) will be the one who takes the least time to trace the error. A demonstration with a transmitter on ultra abort waves, utilising Lechev wires to show the standing waves f ad how they are located and measured i.-t due> soon. At the last meeting in September, members who are taking part in flic set construction coui■petitioii will have their work judged.