If he was going to dedicate a 43 foot antenna to 80m, he easily could
top load it for good performance and efficiency. At my previous QTH, I
put up a 44 foot vertical (it just happened to be how much tubing I had
handy) on top of my flat roof home, guyed with nylon twine at the top
and at about the 2/3 point. The top guy lines included 4 perpendicular
lengths of 10 gauge aluminum wire (Radio Shack guy wire) each about 11
feet long connected to the top of the pole and sloping down at about a
45 degree angle. I had modeled the setup in advance with EZNEC for
resonance and it came out almost dead on when I put it up, even though I
was only able to feed it against counterpoise wires rather randomly
stretched across the roof. The bandwidth was not wide so I still used a
tuner in the shack, but the SWR on the line was reasonably low. I
worked about 120 countries from Arizona with it the first year, although
it took an amp to get the harder ones and it definitely put a strain on
the ears to hear many of them through the band noise. The suggestion
somebody made to use a separate receiving antenna, such as a small
pennant or K9AY loop, is a good one.
73,
Dave AB7E
On 4/23/2011 10:31 AM, Tom Osborne wrote:
> I think I'd stay away from those '43 foot antennas'. We had one of those at
> FD last year and it didn't work all that well for 80. You can make them
> load up, but don't think the efficiency is all that good. 73
> Tom W7WHY
>
>
>
> DX Eng might have some other 80/40 options too.
>
>
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