A FORTY-HOURS’ WATCH

Wanganui Chronicle, Volume LXXXIII, Issue 20183, 27 June 1928, Page 10

A FORTY-HOURS’ WATCH

■ CHEISTCHUKCH ACHIEVEMENT During the last stage of Captain Kingsford Smith’s trans-Pacific flight, three Christchurch enthusiasts, including Mr J. Orbell, kept a continuous watch from 8.30 until noon on the following Sunday, at a station on the Cashmere Hills, provided with a special aerial, mainly for short-wave work. They got some fine long-range results. The object was principally to obtain data on European ’phone stations which transmit in the early hours of thfe morning, New Zealand time. Three receivers were in commission, a Bremer Tully counterphase eight, an eight-tube superheterodyne, and a specially-con-structed short-wave outfit. The latter has four valves, one stage of radio frequency amplification, detector, and two stages of audio frequency, and the set is entirely encased in aluminium. The radio frequency tube is one of the new screen-grid type, and has a very high amplification factor; in fact, it is considered to be worth at least three ordinary stages of radio frequency amplification. Each unit is completely shielded, and, in consequence, capacity effects are reduced to a minimum; this also makes for stability of operation. The set is very easy to control, and, at the samg time, the degree of efficiency is exceptionally high, the receiving combining sensitivity with selectivity. The signals transmitted from the Southern Cross were held continuously until 3 a.m. on Saturday. The strength was exceptionally good, and the Morsje could be heard over 100 ft. from the loud speaker. While the aeroplane was passing through the heavy storm between 8.30 and IUO o’clock, the note of the generator often changed violently in pitch, indicating that the aeroplane was passing through bad weather. alternately climbing and racing. Other short-wave stations heard in the course of the test included one at Saigon, French Indo-China; 2XAD rebroadeasting WGY, New York; 2XAF, its sister station; IDO, Rome, working a station in South America; PKX, Malabar, Java; a German station working Japan; PCJJ, Holland; SSW, Chelmsford, England; GLW, Dorchester, beam station, England; VNB, South Africa; PCG, Malabar, Java; GBL, Leafield, England; AGK, Nauen, Germany; JES and J"EW, Osaka, Japan; NA A, Washington, United States; FW, Ste, Assisse, France; SPW, Rio do Janeiro; VIS, Sydney; 2NM (G. Marcuse), Caterham, England; NPG, San Francisco; LPI, Buenos Aires, South America; and NPM, Honolulu. Apart from the calls listed above, over 20 amateur transmitters were logged, the stations being located in England, France, Germany, Russia, America and Australia. On the broadcast band JOAK and JOBK, Japan, were brought in at strength, but suffered static interfer[cnce. The speeches of welcome to [Kingsford Smith were heard on the Bremer Tully from 4QG at half-past ten in the morning, using a rejector circuit to overcome pronounced fading.