Quoting N4BAA - Jose Castillo <n4baa@cox.net>:
> Top Banders...
>
>> For receiving I took enough wire to install 5 beverages....300 feet was
> the shortest to South America....with ASIA/EU's being 1080 feet long and
> (2) USA's 540 feet long.....and 1080 to VK/ZL. That having been
> said....I could NOT get any of the beverages to play at all.....I was in
> a panic mode! I got a hold of W3LPL, K4XG and some others in an attempt
> to "adjust" something....but to no avail....
>
Jose,
A good ground is not what you required nor necessary to make a Beverage play.
One trick you might try in the future is to *not* ground the Beverage on the
far end but rather insert a termination resistor and then on the other side of
the resistor place a 1/4 wave length of floating insulated wire. This trick
or classic terminated long wire was used in the Arctic where a long wire is
run out on a snow cat and the last 1/4 wave is interdicted with a termination
resistor. (Maybe the actual ground was hundreds of feet or more below the ice
cap.
One down side with this design is that this will make the antenna tend to be
mono band unless multiple 1/4 wave wire for the band are attached. I don't
know if it will perform exactly the same way as a Beverage but the terminated
L/W is quiet and will give directivity off the terminated end and reasonable
F/B with good F/S nulls depending upon total lengths. You might have one of
the Beverage gurus model this taking into account that a 1/2 wave wire may be
a bit short and the full wave or longer terminated L/W would show better
performance. I think the ARRL antenna book has patterns for terminated LW of
a wavelength or more. The may not produce the same wave tilt and low angle
considerations but I am not sure on that.
Before you give up on the Beverage please remember there were some weird
arrival angle stuff going on over the past Weeks. At times my TX antenna was
the only way...other times my K6SE Pennant (FO0AAA design) saved the
day....and at time signals on the Beverage had some skew. But a few nights
ago VQ9LA was in here at 599 solid plus for several hours (from my SS to his
SR ) and could not hear me, not even a peep on his NA Beverage. We did work
eventually and with ease when he listened for me on his 1/4 wave vertical TX
antenna.
In 1969 I operated from Navassa and found that a low dipole slung 90 to 100
feet over Lulu Bay (actual ocean but at virtual ground level above) was an
excellent RX antenna. I wanted to use the famous Navassa lighthouse way up on
the hill for some nice slopers.... but w/o any easy way to get genset up there
the topband operation took place from the coast. (The Navassa Rail System shut
down many years ago even though the tracks are still there.)
In short...I can't tell you the number of times over the years when I thought
my Beverages were in failure mode. I would then hopelessly tramp thought the
Guinea grass, brush and thorny cactus to try and find out why. ("Walking the
Beverage" I think it is called) Then like magic, the next day they would
start to perform again. I think the term is "through snow, sleet, rain, or
fog a true topbander will walk the beverage even in the dead of night!"
Here is a better way to check......
Now I just simply verify the integrity of my Beverages with pre-set AM BC
stations on the high end of the band. I can check S/N F/B B/W and gain all
without an analyzer and effortlessly by just comparing the known and
consistent ground wave levels of various island Am radios stations. Remember
even though my RX antennas may be working the gods of propagation sometimes
have a mind of their own and often there is no easy explanation.
Hope these suggestions will be of use in your future plans.
73
Herb Schoenbohm, KV4FZ
St. Croix, VI
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