RADIO NOTES

Rotorua Morning Post, Volume 1, Issue 61, 3 November 1931, Page 4

RADIO NOTES

"Kathode."

By

A radio reeeiver was recently handed to Kathode for inspection, after having been out on demonstration. The reeeiver in question functioned perfectly before being installed by a local dealer, but on return results were almost nil. Examination showed that the set had been tampered with and rendered quite useless until extensive overhaul had been made. This, of course, meant expense to the dealer which was quite unecessary. Part of the dynamic speaker had been disconnected, evidently for the purpose of using headphones, but on re-connecting one speech coil lead had been soldered to the field coil, and the loose field coil connection had been soldered to the speech coil. On making these alterations, the experimenter found that no results could be obtained, so had set to work and altered the tuning of the roadio frequency stages in the reeeiver. The final result was nothing more than an assembly of apparatus, quite useless as a radio reeeiver. Regulations are shortly to be made to prohibit unqualified persons from tampering with a.c. reeeivers. Reception during the past week has been exceptionally poor. Weak signal strength, with heavy static and fading has been evident on all New Zealand and Australian stations, though the American transmitters KFI, KPO and KGO have. been received with fair volume.

The Rev. W. Constable will leeture at 1YA this evening at 7.40 p.m. His subject will be "George Bernard Shaw." During the International programme from this station, Professor H. Belshaw, Professor of Economics at the' Auckland University College, will speak on "International Economic Co-operation as a Factor in World Prosperity." 2YA's sudio concert this evening will be of the popular type. Mr. Terenee O'Brien (tenor) will sing "Then You'll Remember Me," "Believe Me if all Those Endearing Young Charms," "Killarney," and "Mother Maehree." It will be of interest to local listeners to learn that Mr. O'Brien was a resident of Rotorua as recently as last summer. His Prish tenor voice is partieularly pleasing, and listeners are assured of a musicai treat if they tune in 2YA during his items. Miss Muriel Johns will he heard in songs at the piano. Peree and Les (piano duo) are newcomers to 2YA. A feature of the programme will be a one-act play, "The Signal," written by Helen Gordon. The Salon Orehestra will provide incidental music. 3YA will hroadcast a community danee on the green from Christchurch this evening. The programme from 4YA will be provided by the Kaikorai Band and assisting artists. When constructing a reeeiver from a published design it is as well to renember that any alteration of the ariginal design may greatly affect rejeption.

Radio is no longer in its infancy. During the past decade it has emerged with astounding swiftness from the novelty stage to being a permanent institution, with far-reaching effects on our social life. As recently as 1926, Efrem Zimbalist refused to broadcast and prophesised a short life for radio. He declared that broadeasting was passing through an ephemeral existence and was doomed to oblivion within two years. Just a little over two years later, Zimbalist made his first broadcast. To-day, it is estimated that 26,000,000 radio iteceivers are in use throughout the world. Several listeners in different parts of New Zealand report having heard continental stations on the broadcast band during early morning hours. "Radio Wien" located in Vienna is shortly increasing power from 20 to 100 kilowatts and will operate on 517metres. This station should be heard on average broadcast reeeivers under good conditions in Rotorua and should prove an incentive for early rising among local enthusiasts. The human ear is an inaccurate gange of sound, The same energy may be used at 100 cycles as at 2000 cycles, but the 2000 cycles sound will appear to be very much the louder. Some types of dynamic speakers have incorporated in them a filter which has the effect of eutting out notes above 4000 cycles. This has the effect of making the tone: mellow, but the output of sueh speakers lacks brilliance. It is sometimes an advantage to remove the filter, partieularly if the reeeiver is eapable of delivering an output of over one and a half watts. ZL1CL, Mr. I. D. Shearer, placed his transmitter on the air during the week-end and is at present operating on 80 metres. ZL1GL also operates on that wavelength. Early morning shortwave reception has been good in Rotorua during the past week. The powerful Rome stafcion comes in exceptionally well, bhough the English station in Chelms£ord has not been as reliable. The American stations on the 40 metfe band are well received and Radio Sagon can be picked up any, evening after 11 p.m. at full strength. The Siberian station on 70 metres has tiot been heard for some time.