Two years ago or so the BBC refocused their Astra satellite transponders more tightly over the UK. That meant that areas of Europe used to receiving the BBC, ITV, Channels 4 & 5 with nothing more than an 80 cm dish needed something bigger. (The BBC says it did it to improve coverage in the UK but I think there must be another reason - perhaps so their channels will be viewed by subscription instead of for free. Sky can still be received on an 80 cm dish in the south of France.)
We hoped a 120 cm dish would do. This would have to be on the ground and as free from vibration as possible. (The south of France is a very windy place!) It also needs to be aimed very carefully and easily adjustable in fractions of a degree.
I bought two bolt-down mounting poles from Brico Depot (which is under the same ownership as B&Q and Screwfix but where everything is on display - which is great!). I buried one in the ground with the french equivalent of postcrete. It doesn’t hurt to drill I couple of holes in the pipe and bolt on some studding to give the concrete more grip.
I made a turn table out of four pieces of 6 mm steel plate drilled as shown in the sketch and welded up to form two parts as shown . A big nut and bolt hold the two bits together. The bolt can be tacked to the top plate to make it easier to tighten the nut.
A long handle can be screwed onto the turn table to enable fine adjustments in azimuth to be made. Two bits of alloy make up a pointer. Positions can be scratched on the aluminium or a fine marker pen can be used.
The next page describes the adjustable brace that steadies the dish.