HAM RADIO # 1
Ham Radio...Changing my antenna system...
Ham Radio...Changing my antenna system...
A couple of years ago I've decided to replace my faithful antenna (KLM KT 34XA) that was on the air for about 20 years, already showing sign of times and hard use. The important fact that it doesn't cover WARC bands weighted in my decision, as since these bands were allocated to hams I had to work them using very simple wire antenna systems, loosing a lot of DX so far! Also helping, those repeated and never ending problems with the rotator Yaesu 2800 SDX, showing (since the first day!) more and more an erratic behavior, stopping , starting at its own will...rotators are ham's nightmare...
Its difficult and very frustrating for one that has been on the air , without interruption, since 1977, to stay away of Radio without seeing the 'end of the tunnel'...and , worst, hearing other DXers telling this and that about announced DXpeditions, DXnews causing us all time, and so...not easy.
Decision taken, and KLM down, perhaps too early.
As usual, my good friends CT1EEQ (Luis Rodrigues), CT1EGW (Arlindo Ferreira), CT1BGE (Luis Costa) and old 'DX fox', CT1BWW (Marques), helped me since the first day. In the above photo , CT1EEQ and EGW waving good-bye KLM...
At this time I had already another antenna in the garage: the Optibeam OB 13-6...big and expensive, we will see if its performance is also as spec sheets show...
So, profiting a long and rainy winter (so far ended, crossing my fingers) I start assembling 'the' OB, and immediately I've verified the meaning 'made in Germany', strong, detailed and very well conceived. I should clarify that all my previous antennas (mostly all kind of Yagi beams) were 'made in USA'. The important parameter - weight - confirms that you cannot have everything in one package...far from that, but time of monobanders are gone.
So several photos of "OB's " assembling.
In the above photo we can see one can of a miraculous liquid electrical tape (known brand name) , but as every dark cloud has a silver lining...due to tower decisions (later in next episodes :-) ) my antenna has been partially assembled in the terrace, open air, for more than one year (one hot summer and one very rainy winter) , I can now see that the liquid electrical tape is cracked and peeling...and not, yet, getting strong winds..so...
The photo above shows the boom-to-mast-plate, but this one 'home-made', in stainless steel, as the original one (aluminium) seems, in my opinion, not strong enough. Still to decide if I will use mine or Optibeam's plate (much lighter)...but it impresses how one 70 kg antenna+all stress inducted by external factors (wind, etc) is supported by those (not those showed on pic, because they are quite sturdy) little 4 clamps coming in the package. Still to decide.I know that assembling SS parts with aluminium ones can lead to some kind of electrolytic corrosion, but this situation is common specially when bolts, washers and nuts are SS.
The above photo shows the excellent quality of manufacturing (connection of boom sections). The black 'tape' seen (not provided by Optibeam) is not an ordinary tape, but that one called 'DENSO' tape, normally used to isolate underground piping connections. Literally indestructible, very difficult to remove.
Every connection was carefully sealed with industrial compound (brown colour) and every telescopic connection treated with anti-seize copper compound (best, in my opinion is industrial vaseline! never dries!) Also, in all connections, I've applied , first one layer of self vulcanizing tape then covered by (good) 3M electrical tape.
