Hi Mel:
I would like to encourage your EWE efforts. I've started my third
year with them. I have had *excellent* results.
> Each has ten foot vertical sections,
>one has a 50 foot horizontal and the other a 48 foot horizontal.
Both are
>terminiated by 1200 ohm resistors.
I have three right now which are 40 feet long over flat ground in the clear.
In this area, ground conductivity is *really* poor.
>and I need a six foot wire to the ground rod.
You might try letting it follow the general terrain slope so the end wires
are more nearly the same.
>Ground rods are copper plated steel or copper tubing and are driven
about 4 to
>6 feet into the ground.
Mine are just 2 foot lengths of steel re-bar!
> My next step is to replace the fixed resistors with variable and
so some on >the air tuning...
I tried this with no real improvement--but it was very good to start.
>I think that I need to LOWER
>the antenna to drop noise levels relative to signal levels.
I don't think lower will help except possibly as I said above.
>Optimally I would install a massive
>horizontal ground screen under the antenna
I tried a single surface wire between the ground stakes--it didn't do anything!
I really suspect the main problem with directivity is with the balun
transformers. See
the examples in Jerry Sevick's book "Transmission Line Transformers, 2nd
Ed." Mine copy his and use FT 114-61 cores. Also choke off currents on the
outer of your feeder somehow.
>I'd love to put up a beverage, but space is limited to about 290 feet and
>there are WAY too many trees to detour around.
I also have 3 beverages pointing the opposite ways. They vary from 600 to
900 feet and are a little better than the EWEs, but the EWES are great, too,
with a 10db preamp. Best of luck; see you on the band.
73, Charles - KB5UL - New Mexico
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