DUST IN RECEIVERS

Manawatu Times, Volume LIV, Issue 6808, 11 January 1929, Page 10

DUST IN RECEIVERS

lIOW TO REMOVE IT. Even when the cabinet- of a wireless receiver is carefully constructed and apparently effectively scaled it will be found that there is a tendency'for dust to accumulate on the components. Although the dust itself is practically non-conducting and can cause little trouble if kept drv, usually it tends to collect moisture, and therefore causes serious short circuits in the received. These short circuits result in noises in the speaker, loss of volume, flatness of tuning, and often in the rapid deterioration of high-tension batteries. The cleaning of a wireless set is often difficult owing to the complicated nature of the wiring and the inaccessibility of some of the components, but it can be facilitated by the use of a vacuum cleaner, especially if it be fitted with a blower device as well as suction apparatus.

Dust can also be blown from inaccessible parts of a cabinet by means of a motor-car or bicvclo pump, or a more constant source of compressed air can be obtained for this purpose by inflating an old motor-car inner tube and releasing the air contained in it through a nozzle connected over' the valve piece by a length of rubber tubing. A small, soft brush of the type used by artists can be inserted into even the most inaccessible corners of a cabinet, and will be found valuable in removing dust. In cleaning a receiver special attention should bo given to the vanes of variable condensers. Dust is liable to lodge between condense! vanes, and when the vanes are meshed it will cause short circuits between the fixed and moving plates. Unless some form of blowing device is used it is difficult to dislodge. A slip of thin cardboard cut to a convenient shape can sometimes be slipped between condenser vanes to brush out dust.