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50Mhz LFA loop construction.

My 7 ele 50Mhz  G0KSC  beam  was a bit low band edge tuned. The SWR went up to 1:1.3  at 50.300 and 1:1 at 50.000 the edge to edge dimension of the loop should be 245cm  according to G0KSC I measured  246cm. I calculated 1cm # 200kHz Then i cutted  1cm of both ends (4x sawing) of DE1 and DE2. That was not yet enough. so another time 1cm cutting. Then the matching was  optimal  between 50.000  and  50.500   rising slight to 1:1.2 at both ends. The edge to edge size now is 142cm I used 12mm Alu tubing  for DE1 DE2  and the other elements. The end pieces are 10mm  2 x 1m each  leaving enough length left after bending. DE1 & DE2   134cm  allowing 4cm both ends for the radius  of the end pieces.  With the end pieces maximal inserted  the size is 142cm. I tested it  F/B was real good  it all looks fine. But the...

End of ES season

I transferred my 7el DK7ZB to a 7 element LFA  loop feeded beam by G0KSC  just to see if that could be an improvement boom lenght of 9m80. It seems okay the matching and radiation pattern seems clear. First signal I  heard when I just erected the mast was D4C !  by coincidence. It does not bring more signal   That was also not claimed  it should be a gain in noise and efficiency  the mechanical balance point was changed 50cm to the rear compared with the DK7ZB   http://picasaweb.google.nl/jaapoosten/LFA11Aug?authkey=Gv1sRgCPCrivvtnImiHQ&feat=directlink DK7ZB  with swallows gathering... meaning end of ES DX ! 

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