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Old June 3rd 07, 08:58 PM posted to rec.radio.amateur.antenna
charlie charlie is offline
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First recorded activity by RadioBanter: Sep 2006
Posts: 123
Default 6 Metre Conundrum

I was wondering if anyone can explain to me how it is that the
following antenna puts out a reasonable signal on 6 metres (5-7 over
a 1600 km path from England to Spain. The rig is an ICOM IC 703 and
the tuned SWR is under 1.4:1 over the whole 6m band and 1:1 from
50.120 to 52 MHz.

The antenna is a loft mounted fan dipole cut and resonated for 40,
20, 17, 15 & 10 metres. You can see the design dimensions at
http://www.radiowymsey.org/FanDipole/FanDipole.gif , in practice the
dimensions were all trimmed by around 5 per cent. The final
resonances at the TX were measured as 14.3, 18.09, 21.188, 28.44 MHz
, the centre of the 40m loaded dipole I calculate to resonate at
around 30 MHz. There is a 1:1 balun with around 10 metres of coax
into a LPF and then the 703. No odd harmonics work out for 6 meters,
so I wonder what is doing the radiating?


Charlie.

--
M0WYM
www.radiowymsey.org