I have installed a 253ft Bog,
I used WD-1A a pair and just twisted the two wires together.
Any reason I should separate the pair and just use a single wire?
Can the WD-1A be used for a Bi-directional BOG, or is the spacing too close?
I have installed a variable termination on the North end of the BOG and
a matching transformer
on the South end, for receiving from the north. I'm in the Florida
panhandle about 1 mile from the gulf.
I'm a little disappointed that the Variable termination does not have
much effect between 200 ohms and 1300 ohms.
I use AM Band stations as a guide to the directionality of the BOG and
it does seem to have good directionality,
just no noticeable difference while adjusting the termination. It is
also quiet when compared to a 150ft long wire.
In an effort to make the antenna seem 'apparently' longer I have loaded
the BOG with 9 ferrite binocular cores.
Using info from W8JI's page,
https://www.w8ji.com/slinky_and_loaded_beverages.htm
I originally measured my Velocity Factor as .78 and by installing the
cores I was shooting for a VF of .55
I made a single pass through a single hole in the binocular core.
A single pass through a single hole in the binocular core is about
8.9uh. My calculation said I needed
11.8uh, but I installed all the cores I had and ended up with a VF of
.67, lower but... when I get more cores
I'll install them and test VF again.
Your thoughts?
I have measured my ground rod resistance using the method on page 24 of
the this pdf.
www.weschler.com/_upload/sitepdfs/techref/gettingdowntoearth.pdf
I got 117 ohms on both ends, I bought some calcium chloride and put
2.5 lbs into and
around my 3 copper pipe rods. I pre-drilled the rods every 3" to allow
the solution to
distribute more evenly around the pipes. (5ft rods/pipes) I did this at
one end.
A day later I retested the ground rod resistance, and it was 73 ohms,
some improvement,
and another couple days I remeasured and it was down to 60 ohms.
A week later I added more Calcium chloride and I'm at 34 ohms now.
I just finished retesting ground resistance, North end 34 ohms, South
end 23 ohms.
Is the method in the pdf article a reasonable way to measure ground
resistance?
I used 60 hz, because it's available. My last test used ~ 25V and
supplied 600 mA.
I have no other AC source at a different frequency that would apply
that much power.
I bought a 74AC14 TDR and used it to measure the characteristic
impedance and VF.
I measured the Characteristic Impedance, which I then use to calculate
the matching transformer.
Does the ground resistance show as part of the Characteristic Impedance?
ie. If my ground was 117 ohms and I treated it and it is now 23 ohms,
will my Characteristic Impedance,
impedance drop by 94 ohms?
I measured my Characteristic Impedance as 358 ohms before Binocular core
installation,
and measured 501 ohms after Binocular core installation.
OK guys, this is my first post, there are a few questions, I hope to
get some help on this project.
btw, I did make a video showing how it compares to my long wire antenna
using AM band stations.
https://www.youtube.com/watch?v=QuMwGDK6IhQ&t=51s
Thanks, Mike Knowlton
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