THE RADIO WORLD

Hawke's Bay Tribune, Volume XVII, 23 November 1927, Page 8

THE RADIO WORLD

HINTS FOR LISTENERS CARE OF DRY BATTERIES. Many wireless listeners who use dull emitter valves in their receivers have on hand large numbers of old dry cells which are no longer capable of lighting the filaments of tho valves. Especially in receivers m which only one or two valves of the .06 ampere filament consumption type are used those old batteries can be reconditioned to give in some cases several months of additional life (writes “E.5.H.,” in th 0 Australasian J., About the eaiest method of renewing rundown dry batteries is to obtain an old bit and with a brace drill a hole about 2in deep into the top of each dry cell. The top of most dry cells is composed of wax or pitch, and it can be easily drilled. In the hole- should b e poured a couple of teaspoonfuls of a solution made by dissolving sal ammoniac the salt employed for charging wot batteries of tho kind used for bcllringlng, in water. The sal ammoniac can generally be obtained at any ironmong ers, as it is often used for clean'r.g soldering irons, and for similar p/.poses. After tho solution has been absorbed by the battery the hole iu the top should be filled with melted wax or pitch, or even plugged up with clay. If the battery is a very* old one it will probably be found that therj arc- many small holes eaten in tho zinc-contining vessel in which the battery is made up. In this case the solution applied to the battery will soon soak out and the battery will not last very long. A good way of restoring batteries of this kind is to convert them into wet batteries. This is done by obtaining a jar into which tho battery and its zinc case will slip after the carboard covering has been removed from the battery. Several fairly large holes arc made in Lho zinc case of tho battery, and it is placed in the jar. The jar is then about half filled with sal ammoniac solution.

In a great many cases tho life of dry cells is considerably reduced Iw. careless use. Many receivers contain a potentio-metcr. which is connected in the form of a resistance right across the battery as long as the battery is left connected to tho receiver. Although the potentiometer draws a relatively small current from the battery, the constant drain it imposes rapidly runs the battery down. It is highly desirable that when dry batteries are used for filament lighting circuits which require tho use of a potentiometer should be avoided. If such circuits arc used care should be taken to sen that the battery is disconnected -from the potentiometer when the receiver is not in use. Merely turning off the valvs by means of the rheostats will not be sufficient, as tlie potentiometer will still be left in circuit with the battery running it down. A further causg of rapid deterioration in dry batteries both for filament lighting and high-tension supply is lack of care in storing the batteries. Heat tends to set up chemical action vn a dry battery which causes it to deteriorate rapidly, and it is therefore desirable that wireless dry cells should bo stored in the collcst spot available, while when they are in use they should never bo exposed to heat. Dry conditions arc also essential, and damp and moisture dropped on to tho batteries or around the table or bench on which they nre standing will quick ly run them down.—“flagnavox” in “Otago Daily Tinies.” WHAT TO DO WITH A CRACK LING SET. Tho complaint that a set's rcccp tion has become noisy and given lo periods of unaccountable crackling is more frequently heard than the straight-out plea that it has broken down completely. This, of course, is because these symptoms are usually tho forerunner of complete silence, and if steps arc taken in time, they can, like a bad cold, bo prevented from developing into something else. Fully 90 per cent of set noises are due to tho batteries, and of this again, a large proportion can be laid at the door of the “B” batteries; they are, so to speak, guilty until they arc'proved innocent. For this purpose, a small, inexpensive voltmeter should be kept handy so that hotn A and B batteries can bo tested. Even this, however, is by no means an infallible test, as often, the voltage will read full when the batteries arc noisy. In this case, tho trial of other batteries is tho only certain method Static should never bo confused with set noises, tho difference easily being discovered by “shorting” or disconnecting tho aerial, when, if the cause is static, the noises will cease. Faulty electric lighting systems or electric fans will cause the same symptoms, the only remedy in this case being tho removal of tho cause itself. Little can be done to the set to help at all. Connections are- tho next worst offenders. An intermittent open or short circuit, a badly soldered joint, or a loosely screwed terminal will cause more “unexplainable” trouble than it seems possible that one set could be heir to. Sometimes, a. hard shake will locate the faulty connection or at least determine tho location of the crackle or noise; usually, however, it is a matter of a thorough search, the little item known as grid leak ean also offend in this respect. It may be of the wrong valve, but more often it will bo found that it has broken down. or. if a cheap one, inherently faulty. Valves in themselves are seldom responsible- for trouble of this kind, although they are often tho cause of weak or “musty” signals. —“Magnavox” in “Otago Daily Times.”

PROGRAMMES FOR TO-NIGHT. IYA, Auckland.—6 p.m.: Children’s hour. 7.15: News ana reports. 7.30: Talk on “Physical Culture” by Mr. N. Kerr. 8: Studio concert. 2YA, Wellington.—Silent day. 3YA, -Christchurch 6 p.m.: Children’s hour. Uncle and Mother Hub bard. 7.15: Addington market reports. 7.30: News and reports. 8: Chimes; relay of orchestral selections from Crystal Palace Theatre Orchestra under the direction of Mr. A. J. Hunz; opening chorus, Edgeware Concert Company. “May Morning”;

pianoforte duet, Ellis Fraser and Olive Robson, “Qui Vive”; vocal duet, Misses Daphne Lawrence and Hilda Smith. “Somewhere a Voice is Calling”; violin solo, Alias Irene Morris. “Sicilienne and Ragandon,” Kreisler; elocutionary, Miss Esme Evans, “White Roses”; instrumental trio, Christchurch Broadcasting Trio, “Moderato Allegro Passionate,’’ from “Trio in D Major,’’ Ressiger: talk, Rev. B. Dudley, F.R.A.S.. “The Sun and His Wonderful Story.” M.S.; vocal solo, with humming chorus. Edgeware Concert Company and Master Gordon Smith, “Sleepy Hollow Tune”; part song, Edgeware Concert Company, with xvlophone accompaniment, “Moonlight and Roses”; relay of orchestral selections from Crystal Palace Theatre: humorous recital. Miss May jfrenberth, “Back at Squashville”; piano solo, Miss Edna Moore, selected; contralto solo. Miss Hilda Smith. “Break, Break”; violin solo. Miss Irene Morris, “Adagio and Allegro, - ’ from “Sonata in A Major,” Handel; humorous chorus, Edgeware Concert Company, “-Mary Had a Little Lamb,” “Mother Hubbard”: vocal solo. Ellis Fraser, selected: instr.imental trios. Christchurch Broadcasting Trio, (a) “Serenade.’’ LangeMuller, (b) “Dreaming.’’ Schumann, (c) “Entr-acte and Valse.” from “C'oppelia Ballet Music,’’ Delibes; vocal solo. Miss Elsie Burson. “She Sang Aloha to Me,” with steel guitar accompaniment; part sone Edgeware Concert Company, with steel guitars. “Hawaiian Part Song”; vocal duet. Misses Daphne Lawrence'and Hilda Smith, “I Wish 1 Were a Tiny Bird”; i>’nologue, Aliss Esme Evans. “Play, trine”; humorous recital. Miss May 'fernberth, “Terrible Tommy”; voeil solo. Miss Esme Evans. “Kreisler’s Cradle Song - ’; vocal duet and chorus. Ellis Fraser and Esina Evans with xylophone accompaniment. “Tel] All the World” ; voca] solo. Miss Marion Evans. “Youth and Spring”: vocal duet. Misses Rose Smith and Kathleen Robertson. “Good Night. Pretty Stars”: soprano solo. Miss Daphne Lawrence. “Wings”; final chorus, F<lgeware Concert Company. “Ghosts of Little White Roses.”

2BL, Sydney.—B p.m.: broadcasters’ Topical Chorus, the Thomas Kelaukile Bell Trio (Hawaiian entertainers), Mr. Harry Cash (comedian), the Canterbury District Band. Mr. Dudley Helmrich (baritonel Mr. Moore Macmahon (violin solos).

3LO. Melbourne.— 7.ls p.m.: i<tr. R. Crowe, on “Marketing Methods”: Mr. E. Bate, on “Generation and Distribution of Electricity in Victoria”; Captain C. H. Peters, on “Books.” Artists: Senia Cliostiakoff. Dorothea Macmaster. Beatrice Ter nan, Marie Lawton. Madeline Knight, Frances Lea. Newport Workshops Band, Joe Aronson and his Synco-Symphomsts.

4QG, Brisbane.—B p.m. ; The first portion of to-night’s programme will comprise three-quarters of an hour's classical music by Mrs George Sampson’s party. This will be followed by a varied Studio programme.