Wednesday, 10 September 2014

Gilding the faded lilly

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It is now half way through September. Months have passed since my last update. I wish I could report improved reception but it remains highly variable without obvious reason. We lost the signal very early the other day [3pm] so I re-pointed the dish for signal Quality on Astra 2E UK Spot Beam.

It seemed that the U-clamps on the steel support post had worked loose. Allowing he dish to rotate sightly in the recent high winds. I was even able to push the dish around the post by hand. It is highly likely that I had re-adjusted the dish at some point and simply forgot to fully re-tighten the 19mm nuts on the U-clamps. 

So far the coax cable had been held to a feed support arm with tie-wraps. This had allowed changes in skew of the LNB depending entirely on [arbitrary] cable tension. I resolved to do something about this.

Sadly the dish to arm fixing nut still refuses to budge. I even brought out a vice and clamped that firmly to the arm to have some resistance to work against. Then I applied a 3' pipe to a hex socket bar without the least change in tightness of the nut. It really seems to be fixed for life. I had discovered a white powdery material when I had finally been able to remove the top nuts at the feed end of the arms. The enormous effort involved in their removal suggests some sort of thread locking compound. Or, at least, one that had dried hard over the intervening decades.

Fortunately the stainless steel nuts at the dish end are already bored large enough [7.5mm] for a modern coax cable. So I used a rechargeable drill to bore an 8mm hole in the arm itself not far from the feed. Then I laid the drill gently over while still turning fast to force a suitable exit angle on the newly drilled hole. Finally I tidied up the now-oval hole with a round file. The hole was originally made 7.5mm but this proved far too unforgiving. The cable would not pull through an oval hole without risking serious damage to the insulation and covering. 

Getting the coax to exit the 8mm [oval] hole from within the tubular arm was quite another matter! In the end I made up a stiff wire hook and was able to coax the copper wire core out. Things went much more smoothly after that.

No sooner had I pushed the cable through the arm than a spider moved into the hollow nut behind the dish! I forced an eviction just long enough to take a picture. Whereupon the spider returned to its layer.

Reception still arrives and dies again at highly variable times. Sometimes reception is possible from 8am to 6pm but very often an hour [or two] less at both ends of the day. Weather seems irrelevant except during thundery cloudbursts. Ordinary and even heavy rain seem not to affect matters much at all.

Nothing I try seems to make reception any more extended or reliable.  I am still wary of risking further investment in a new receiver in the vague hope greater sensitivity. Or, rather, a receiver with a lower reception threshold before the freezing and stuttering, presently endured. On the FortecStar Passion HD  this is always when the indicated signal Quality falls below 53% regardless of Signal level.

Should an online BBC TV service ever be offered I'd take down the huge dish without a qualm and finally accept defeat. Only evening TV holds any real interest and then only occasionally. Being limited to daytime TV makes it hardly worth the effort [and expense] of setting up the dish in the first place!  

Click on any image for an enlargement.

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