Tales Out of School from Bill Hite (continued)

. . . When commissioning the WF44 radar at Mascot we discovered an interesting fact. The dish consisted of a front face and a back supporting structure with a cavity in between. To prevent it filling with water when it was horizontal ie at 90 degrees elevation, there were perforations in the front of the dish and matching drainage holes through the back. However, if the dish was parked vertically, or thereabout, some rain or condensation running down the face of the dish would run through the perforations and the cavity would collect the water (there were then no drain holes in the base of the dish).

This was discovered when moving the dish by hand to check the limit switches. The person (me) who was underneath pushing on the dish was drenched with the water that then ran out through the holes in the back. Needless to say, after this, it was usually the unsuspecting Regional assistant who got the job of pushing the dish from underneath.

. . . When designing a small add on unit for the WF44 radar it was decided to use a similar construction. The unit would be a small metal box with two plug-in circuit cards each fitted with a front panel with test points for monitoring. The problem was how to ensure that the dimensions of the panels were a match for the box which was made out of mild steel, bent into shape and spot welded. The guru on these matters was approached; his answer to the problem was very simple, we would annotate the drawing with the comment "panels to be trimmed to fit the box dimension". A neat solution if it wasn't for the fact that when asked to have the units manufactured, he had the boxes made by one company and the panels by a different company.

. . . The magnetron blower motor for the WF44 radar transmitter caused a lot of problems in the early days, the current version being the third type that was tried. The second type was a smaller unit that ran at a very high speed; it was also high speed in cutting out its bearings. At Laverton they carried out an experiment called serial sounding in which they were flying radiosondes continuously for a month. The blower motor failed right at the start and as we didn't have any spares we used the station's Hoover vacuum cleaner set up as the blower. That appliance worked continuously for a month, without needing to be turned off.

Bureau of Meteorology