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 50MHz season is over and I replaced the beam with my HF multi-band again.
The beam waits on the attic for next season.
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 50MHz season is over and I replaced the beam with my HF multi-band again.
The beam waits on the attic for next season.
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