Post_Office_1965-1966 — Page 19

to disrupt various V.H.F. circuits, were investigated and cleared. During these and routine investigations a total of 136 visits were paid to work premises, resulting in 288 machines being referred to their owners for adjustment or repair. Altogether 182 unlicensed machines were found distributed through 45 of the factories visited. Another thirty cases of interference attributable to other causes warranted intensive investiga- tion. Eight cases of domestic receiver interference were also handled.

Frequency Monitoring and Testing

80. Since December 1965 the operating frequencies of the trans- mitters of 34 Commercial Mobile Radio Station Licensees have been checked. These measurements covered a total of 17 fixed, 44 land and sea mobile, and 20 portable equipment.

81. Several prototype plastic welder machines, intended for sale on the local market, were submitted to the Department for frequency- stability and field-strength measurements.

82. Regular routine testing of non-directional beacons was carried out in accordance with the requirements and recommendations of the International Civil Aviation Organization.

Government Telephones

83. The Division maintains records of the 8,148 telephones con- nected to the public telephone system for all Government departments, together with 780 telephone instruments connected to Private Automatic Exchanges in different Government offices. The maintenance, transfer and installation of these latter instruments are undertaken by contract service which is checked and controlled by the Division. Eight P.A.B.X. systems have been installed and nine P.A.B.X. systems were planned during the year.

Maintenance

84. Routine maintenance was carried out on a wide variety of electro-medical apparatus and electronic devices for the Medical and Health Department, on V.H.F. radiotelephony equipment for the Water- works Section of the Public Works Department and the Prisons Depart- ment and the radio, radar and special equipment on the Agriculture and Fisheries Department research vessels.

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