AERIALISMS

Sun (Auckland), Volume III, Issue 741, 14 August 1929, Page 16

AERIALI SMS

Tumng coils should always be spaced well away from copper screens or similar metal surfaces. :3 I! H: Twisted. flex should not be used for long loud-speaker lead-s, as it is gen—erally an advantage to keep the.two leads well: separated from each other.

If two condensers are used in 3.11 ordinary choke-output circuit, remember that they are in series with one another, and that this will greatly reduce the tea! capacity of the arrangement.

Do not let telephones fall on the floor or drop carelessly on the table, as a. sharp shock is likely to destroy the permanent magnetism.

SPECIAL DANCE NIGHT

[AUSTRALLAN EVERY TUESDAY i .__. 3 Every Tuesday night has been set laside as a. special dance night by the ‘Australian Broadcasting Company for the remainder of the winter. A special dance band of 12 players will broadcast right through from 8 p.m. till 11.30 p.m., and will play a solid group of dance numbers broken only: by popular songs. This is the biggest 1 broadcasting dance band yet to be: used and will no doubt prove popular with thousands of listeners. Therel will be definite continuity about those dance nights throughout the Winter, This will enable listeners who have powerful sets installed in their homes to set. this aside as their regular dance night. Mr. Cec. Morrison, one of Australia’s youngest conductors, Will have charge of this special band. He has had considerable experience in broadcasting and has personally selected each member. They are all men who can play two or three instruments, are thorough musicians, and Mr. Morrison has the added advantage of having a music library of over 2,000 of the very latest dance music to choose from.

ANSWER TO CORRESPONDENT

B.C.—The Japanese station you refer to is probably J.0.A.K., Tokyo, which uses 1.000 kw. The wave-Xength is 375 metres. The best time to receive this station in about midnight on Sundays.

One of the reasons for the popularity of the split—primary method of H.F. coupling is the fact that one side of the secondary winding is at earth potential, so if the moving vanes of a tuning condenser are joined to this end of the coil, hand-capacity effects will be negligible.

AUSTRALIAN BROADCASTS

SYMPHONY ORCHESTRA One of the permanent features of the Australian Broadcasting Company will be the National Broadcasting Company’s Symphony Orchestra under the conductorship of Mr. Horace Keats. It will consist of 14 players, each of whom is a solo artist as well as being an accomplished orchestral player. Mr. Keats intends to have instrumental solos accompanied by the balance of the orchestra. whenever the opportunity offers. Included in the combination will he a pedal organ which will provide a. solid background for the tone, colour and individuality of the other instruments. The National Broadcasting Company’s Orchestra. does not intend to present a too heavy programme. Great care, however, will be exercised in endeavouring to include at least one educational or symphonic number in each programme.

POLARITY TEST

Busy amateurs on the look-out for a rough-and-ready. but nevertheless satisfactory test for determining the polarity of their batteries cannot do better than employ the following method, which although, of course. not being as sensitive as the more refined chemical tests, works quite well on potentials of over four volts. The test is simplicity itself. Take an ordinary potato and cut a slice from it. Apply to the surface of the slice the battery electrodes, keeping them about half an inch apart. After about 10 seconds’ contact with the freshly—cut potato surface the positive electrode will give rise to a dull-green mark, the area or contact, of the negative electrode remaining unstained. A freshly—cut onion gives somewhat similar results, the stain, however, at the positive pole, in this case, being brownish. The onion test, however, is rather less sensitive than the potato test, requiring higher voltages in order to give results.