RADIO NOTES

Timaru Herald, Volume CXXXVIII, Issue 19942, 29 October 1934, Page 13

RADIO NOTES

ON THE BROADCAST BAND . Although there are 1500 or so sets licensed in Timaru, fewer than 150 of their owners are members of the Timaru Radio Club, and the average attendance at the Club’s meetings does not reach 15. When it is considered that the Club is about the only one in the Dominion which is not concerned with some sectional interest—such as a B station—that is a reflection on the radio public of the town. It can be said without fear of contradiction that the Timaru Club has done more in the interests of the general body of listeners than any kindred body in New Zealand and its membership roll should be trebled. The blattnerphone process, which is extensively used by the 8.8. C. to record big events in England so that these may be broadcast by the Empire stations at suitable hours to different overseas zones, has possibilities that might well be exploited in Now Zealand. Any important function or contest, say in Auckland, might be “recorded” during the day, and broadcast at night so that the whole Dominion might listen in. Local interference has been particularly bad in parts of the town lately, and it is hoped that there will be as little delay as possible in putting the anti-noise regulations into effect. It is stretching the aerial a bit to suggest, as one YA mid-day speaker does, that he receives letters from Australia covering matter dealt with in his talks. The Japanese Government has ordered three high-powered transmitters, one of which is to be of 150 kilowatts. The most powerful stations in Cherryblossoinland at present are of 10k.w. The distance over which a line leak can radiate and cause interference is indicated by a clean-up made recently by the Power Eoard staff. Serious interference experienced by many Timaru listeners ceased when a leak in the Hook district was located and rectified. A slip by a Sydney B station announcer: “These nude items—er, news items—appear in the ‘Sun’.” Quite likely he had been studing the corsetry advertisements.

Australian cricketers get a lot of pickings on an English tour besides their £6OO bonus, their spending allowance, and liberal expenses. Among the gifts received by each member of the team now returning was a radio receiver from a well-known factory.

j The plan of “recording” a daylight broadcast, for reproduction at night, was adopted by Australian B stations in connection with the opening of the Melbourne Centenary as well as for race meetings. It is pretty certain that the process will become universal, and it opens up wonderful possibilities for listeners. The machine for cutting records that has been imported by one station rejoices in the portmanteau name of Schallfolienschneidmaschine.

A Lithgow (N.S.W.), using a 5-valve kit built broadcast receiver, claims to have picked up London with as much volume as many local stations. That is something that no New Zealand DXer has accomplished—in fact nobody in the Dominion has submitted proof that he has received any English broadcast station—and the Lithgow man will have to produce corroborating j evidence.

The P. and T. Department pursues its policy of gradual extinction of B stations. 4ZM Dunedin, which was owned by a Dunedin hardware firm which handled radio, went off the air some weeks ago when the firm closed down. The stock, incuding the transmitting apparatus, was soic., and the purchaser applied for a transfer of the license to new premises. This the Department uncompromisingly refused, and now it has closed the discussion by buying the plant. 4ZF’s power was only 7 watts, and it operated intermittently. Dunedin has so many small stations that one more or less is a small matter, but the incident indicates that in addition to “no new licenses,” the Department intends to grant no transfers.

A long struggle continues in the United States courts over the patent rights of the feed-back circuit. The feed-back has the valve so designed that part of its output is fed back to the input to secure amplification. This reamplification is known as regeneration. With certain arrangements of the feed-back circuit and valve, the circuit acts as an oscillator, i.e. it generates oscillations or alternating currents. In 1913 and 1914, four Americans filed applications for patents for a feed-back circuit. The last to file was Dr De Forrest (well-known as a valve inventor), but be claimed to have made the discovery at an earlier date than any of the other three. A patent was granted to one Armstrong on October 6, 1914, before De Forrest’s application was .filed, and then began the legal contest between the two. In 1924 the Commissioner of Patents confirmed the priority of Armstrong’s invention, but the Court of Appeals decided in favour of De Forrest, and patent rights were granted to him. Still the battle continued, and although Justice Cardozo in May last upheld De Forrest as inventor of the feed-back, a month later he granted a stay of the mandate on a petition being presented for a rehearing on the ground that the decision was rendered on an error of scientific fact. De Forrest’s claim to priority has been accepted on the evidence of notebooks he produced to show that he made the discovery in 1912 although he did not file application until 1914. Now the Armstrong party will attempt to prove that De Forrest’s notes do not prove that he had recognised the principle of feed-back until others had applied for patents.