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I decided to get rid of the arm/boss brackets altogether. However, the boss was a tough piece of aluminium plate which had been hydraulically pressed. The last thing I wanted was to ruin it. So I trapped the centre of the boss very tightly between two disks of MDF in the vice. I could then tap the ears with a plastic headed hammer until they matched the angle of the arms. All without damaging or marking the boss. It took several attempts and I had to check the angles carefully before I was fully satisfied. Had the centre of the plate boss itself been bent the (skew) clamping ring would no longer have fitted. Nor would it have held the feedhorn flat on the boss.
I found that having the wrong angle on the boss ears bent the support arms. This pulled the feedhorn all over the place as I tightened the arm holding screws. Eventually the angles were all correct and the arms now straight and relaxed. By a fortunate coincidence they were also exactly the right length!
The mounting is now firmly fixed on my massive support pole. Which started life as the base of a professional drawing board. It had a hydraulic lift when purchased cheaply in a flea market. Its massive, flared, cast iron base is further loaded with concrete bars to hold the dish down in high winds. The 'pole' itself is a very thick-walled, steel pipe of 70mm diameter. Sadly it can no longer move up or down after years of exposure to the weather.
The mounting now offers slow motion adjustments in both elevation and azimuth. With the dish being so large (6' in diameter) it has a very small field of view. Trying to turn the whole dish around the pole would be far too coarse a change in angle.
The new, hot galvanized, elevation screw ideally needs spacers so that the nuts can turn more easily without friction. The nuts are also partially enclosed by the pivot support bracket. So spacers would expose them better for the use of a spanner/wrench. Not that this has proved to be a particular problem but I do like to avoid such minor problems where possible. I have replaced some of the rusting mounting screws with stainless steel. As are the new feed supporting, arm fixing screws.
While I can easily get the stronger channels there is still absolutely no sign of the weaker ones. This is a very disappointing result given the time and effort spent on this project so far. I am receiving reception advice from satellite forum members far more expert and experienced than I. Installing satellite dishes for successful reception has never been so difficult as with this one. All due to the weakness of the intended signals.
Following expert advice on the Astra2 satellite forum I concentrated on a particularly strong channel on the same satellite. By paying careful attention to azimuth, elevation, focus and skew I was able to raise the signal Quality reading to a much higher level than before. The cheap Satfinder meter was not remotely up to the task. Showing increased signal level and audio output just as signal Quality fell on the TV screen.
Once I had achieved the best possible alignment I was able to obtain many of the weaker channels in the UK Spot Beam. Sadly my success was short lived. These same channels became too weak to show smooth video and continuous audio shortly afterwards.
Since the strong channels went on getting stronger and showing even better Quality I think I can safely conclude that the dish has not moved. Either the dish is not large enough for my location. Or it is simply not efficient enough to offer long term viewing at all hours of the day and night. One could say that the journey was rather more interesting than reaching the final goal. I am now suffering from severe project fatigue and considering my options.
Following expert advice on the Astra2 satellite forum I concentrated on a particularly strong channel on the same satellite. By paying careful attention to azimuth, elevation, focus and skew I was able to raise the signal Quality reading to a much higher level than before. The cheap Satfinder meter was not remotely up to the task. Showing increased signal level and audio output just as signal Quality fell on the TV screen.
Once I had achieved the best possible alignment I was able to obtain many of the weaker channels in the UK Spot Beam. Sadly my success was short lived. These same channels became too weak to show smooth video and continuous audio shortly afterwards.
Since the strong channels went on getting stronger and showing even better Quality I think I can safely conclude that the dish has not moved. Either the dish is not large enough for my location. Or it is simply not efficient enough to offer long term viewing at all hours of the day and night. One could say that the journey was rather more interesting than reaching the final goal. I am now suffering from severe project fatigue and considering my options.
Click on any image for an enlargement.
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