I thought this would be appropriate. I am currently building 2 two wire
beverages
using W8JI's article from Communications Quarterly. One is NW/SE for
Ja/carib(700
feet), The other is NE/sw at 520 feet-currently a single run toward EU. These
are
able to be installed with the kind permission of the farmer who owns the fields
behind my house.
The NE beverage runs at 60 degrees for 200 feet then turns to about 79 degrees
for
the remainder of the run. All wire is supported off 2 x 2 treated lumber using
electric fence insulators ($3 per 25 at Farm and Fleet). Height is 8 feet and I
drive a 32 inch wood stake in ground and screw the 2 x2 x8 to it (lets hear it
for
rechargable drills). The ground is mostly sandy and even in the winter I can
drive
ground rods in my yard. This is terminated in 550 ohms and appears to work a
magnitude better than the EWEs I've had for several years. More front to back
and
quieter. The transformer is one I had from a previous project and was thrown
(literally ) together on the Friday before ARRL (hence the 70/60 degree
bend--strung in the dark!
The NW/SE beverage is constructed the same way except it is 700 feet with the
last
100 feet on each end sloping down. It seems to be working now after I got the
beads
that W8JI used in his article. Before that I had some different cores and just
juryrigged some transformers with little success. The current system shows less
than 2/1 SWR up to about 7MHZ with some varation in SWR. I need to play some
more
with the reflection transformers and termination. The article calls for using
#26
wire in winding and I have found that Radio Junk enameled wire is VERY
substandard.
In fishing the wires through the cores of .1 inch diameter the paint easily
rubbed
off leading to several shorted turns and direct shorts to the cores-care must
be
taken here. Tom, W8JI uses 450 tramsmission line but I already had the wire and
had
to calculate the transmission line impedance and beverage impedance to wind
different ratios of reflection transformers-still working on that.
Performance has been proven just this morning. I heard little peeps of JA on
160-condx were not good but on 80 the JAs were Q5 S5-7 on the beverage but in
the
noise on the vertical transmit antenna(1/4 wave with elevated radials). They
disappeared when I switched to SE! I heard an HS0 weakly but it was after my
sunrise. In listening to several BC stations of known location I have found
that
the F/B is nominal at 10-15 db but sometimes much greater depending on condx.
Left to do:Install second wire to NW and straigten Ne wire while lengthening it
to
580 (word has it Santa is bringing me a butane soldering kit!),build up of the
relay swithcing for the NE/SW pair and fiddllng with the transformers and
terminations.
If anyone would like further updates and share notes please respond to my
e-mail-I'd be glad to learn from your experiences (Tom-if ur lurking I do have
a
question about the reflection transformers)
Gaud-what a man will do for a hobby!
CU on Topband
73 Dan W8car
w8car@netohio.net
Merry Xmas!!!!!
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