Anomalous Reception of Very-low-frequency Signals in Australia and New Zealand

Abstract

ROHAN et al.¹ have observed, at Salisbury, Australia, what they describe as a ‘peculiar phenomenon’ when monitoring signals from Station GBR, Rugby, England, on 16 kc/s. The normal beat frequency, derived from the comparison of the received signal with a locally generated high-stability oscillator, on four specified dates suddenly increased for periods lasting 8–30 min. These disturbances were not observed by the British Post Office at Dollis Hill; the signal transmitted by GBR must therefore be assumed to have been normal. Furthermore, Station NBA, Panama Canal Zone, operating on 18 kc/s, compared with the same locally generated source, did not exhibit the same phenomenon. Allan² confirms that very similar results were also obtained at Lower Hutt, New Zealand, on at least two of the dates mentioned, and anomalous records were obtained at the Wellington Time Service Observatory on the two remaining dates. Typical frequency deviations from normal on these occasions ranged from 4 to 13 parts in 10⁸, and the amplitude of the anomalous signal is quoted as 4–5 times greater than normal. Allan concludes that a powerful and frequency-stable transmitter, situated relatively near Australia and New Zealand, is able to operate on 16 kc/s.