ON the AIR Fare For Listeners-In

Sun (Auckland), Volume 1, Issue 9, 1 April 1927, Page 4

ON the AIR Fare For Listeners-In

NEW ZEALAND PROGRAMMES New Zealand broadcasting stations transmit as follows: IYA (AUCKLAND), 420 metres 500 watts. This evening's programme is as follows: 3 p.m. to 4.30 p.m.—Afternoon concert. 6.30 p.m. to 7 p.m.—Children's session; Uncle Frank. 7.15 p.m. to 7.45 p.m.—News and reports, etc.; talk by Mr. G. Campbell, •'Motoring Notes.” 8 p.m. to 10 p.m.—Chimes; relay of orchestral selections from the Rialto Theatre under the direction of Mr. E. Engell; contralto solos, (a) “Elizabeth’s Reply” (Warren-Shaw), (b) “When all was Young” (Gounod), Miss R. Moselen; sketch, “Joe Smith from ’ome," Mr. J. Collier; violin solo, “Yalse Triste” tSibelius). Mr. M. Richardson; organ solos, selections. Mr. A. E. Wilson; organ and pianoforte duos, (a) “Finlandia” (Sibelius), (b) “Spring Song” (Mendelssohn), Mrs. Brame-Clarke and Mr. A. E. Wilson. Interval and weather report. Organ solos, selections, Mr. A. E. "W ilson; soprano solos, (a) “False Prophet” (Scott), (b) “Wondering Why” (Clarke), Miss G. Hosking; violin solo, selected. Mr. M. Richardson; contralto solo, “Berwick Market” (Drummond), Miss Moselen; sketch, Mr. Collier; soprano solo, “Little Bare Feet” (O'Hara), Miss Hosking. 3YA (CHRISTCHURCH), 400 metres, 500 watts. This evening’s progiamme is as follows: 3 p.m. to 4.30 p.m.—Afternoon concert. 7.15 p.m. to 7.45 p.m.—News and reports, etc. S p.m. to 10 p.m.—Chimes; relay from the Addington Showgrounds of description and music of the Military Pageant. 4YA (DUNEDIN), 380 metres. 750 watts. This evening’s programme is as follows: 3 p.m. to 4.30 p.m.—Afternoon concert; chimes; studio items; relay of selections from the Savoy Cabaret; social notes, etc.; travel talk; relay from the Savoy. 7 p.m.—Children's session; Aunt Diana. 7.30 p.m.—Market reports and news. 8 p.m. to 10 p.m.—Studio concert and relay of dance programme from the Savoy Cabaret. 2YK (WELLINGTON), 295 metres, 120 watts. . _ „ This evening’s programme is as follows: 3 p.m. to 4.30 p.m.—Afternoon concert; studio items and relays of selections from the New Adelphi Cabaret by Manuel Hyman’s Exhibition Band. 7 p.m. to 8 p.m.—Children’s session; Aunt Jo and Uncles Ernest and Bill. 8 p.m. to 10 p.m.—Chimes; studio concert and relay of dance programme from the New Adelphi Cabaret by Manuel Hyman’s Exhibition Band. NOTES Consistent reception from both New Zealand and Australian stations was enjoyed last evening. The popular Sydney station, 2FC, transmitted an excellent programme. The 2FC jazz band gave several items and the rest of the programme took the form of a naval concert. There was a decided absence of static and this programme came in clearly well up to midnight. New Zealand stations also came in well. The consistent reception and absence of disturbing atmosphericconditions was probably due to the cold night. Reception can be expected to improve as the cold weather advances. SHORT-WAVE BROADCAST Advice has just been received that station P. C. J. J., operated by the Phillips Glow Lamp Works, Eindhoven, Holland, will be giving a special broadcast transmission next week. On Thursday, 7th. and Fridav, Sth, the time of transmission is 2 54 a m., while on Saturday, 9th, the time is 5.54 a.m. These are New Zealand times. The wave-length is metres. The power to be used is not stated, but we are advised that the station has been heard several times by the Canterbury College at considerable strength. The Radio Editor will oe pleased to receive reports from readers who may hear any of these transmissions. SPARKS AND INTERFERENCE Sparking apparatus may produce interference. Sparks are produced m the normal operation of many types of electrical apparatus, such as motors, buzzers, internal combustion engines, A - ray apparatus, violet-ray machines arm some forms of battery chargers. Sparks are also sometimes produced at defective insulators, transformers, etc., of electric wire lines. Sparks usually give rise to electric waves, which travel along t.ie electric power lines, and by them are radiated out, and are then picked up toy radio receiving sets. The noise thus produced in a radio set may come from a disturbance which has travelled several miles along the power wires. ELECTRICAL INTERFERENCE A frequent cause of electrical interference with broadcast reception is the presence of alternating current power wires near the aerial or receiving set. Lowfrequency voltages are induced, and tne resulting current flowing in the receiving circuit causes a humming sound in tne loud speaker. The low pitch of the hum will usuallv identify this source of interference. In direct current power lines in which there are fluctuating voltages due to varying loads, a similar interference may arise. A method of eliminating. or, at least, reducing, the magnitude of this interference is to place the aerial as far as possible from the wire lines and at right angles to them. When the interference cannot be eliminated by such means the proper choice of a receiving set may help. The use of one or more stages of radio-frequency amplification should help to filter out the audio frequency interference. It has been suggested that audio frequency interference might be shunted round a receiving set having a series aerial condenser by connecting between tnat aerial and earth terminals of the set a high resistance, which will offer a lower impedance to the audio frequency than will the receiving set itself.

WHISTLING Where a steady whistle occurs analyse carefully. Should this occur wherever the dials are set it may be a faulty grid leak or C battery, or the latter may be reversed. If it occurs only when the set is in resonance the cause is usually other than the receiver itself. If heard only Vhen in resonance and at the lower setting of the dials, the set may have a certain regenerative action. As the radio-frequency receiver depends upon an absence of regeneration by some balancing out or resisting method to check this tendency', an increase or decrease of plate potential may be the cause. A neutralised set may require a slight adjustment of the neutralising condensers, due to altered plate potential or new valve. Reduce filament brilliancy on a near-by station, when tuned, and if signals clear then it is a sure sign that the set requires reneutralisation. If you take out detector valve and the whistling continues look to the grid leak. When the receiver is touched or jarred slightly, clicks may indicate a defective valve or loose connection. If of a ringing quality it is usually a microphone valve; but if harsh, a broken wire or loose connection. In the tracing of connections the restoring of valves one by one may confine the trouble to one valve, or its circuit. The exception may be the last valve, as the removal of this disconnects plate supply to the loudspeaker or its jack. If in this jack reception is quiet and satisfactory the break may be in the ampiifier or its special power supply. Defective grid leaks most frequently' cause steady clicks in the receiver if these clicks are unaffected by a jarring of the set. In the case of hunting for a broken wire, check power, inspect connections, aerial lead-in, ground, leads to rotors of condensors, variometers, etc. Should the dial of a variable condenser be rotated and at certain points clicks are heard this is usually due to shorting of plates, dirt between plates, or bad rotor connections.