[Lowfer] NC

[Bill Ashlock]

John A,

>The transformer coupling does make sense. In effect, you are >connecting a 
>"medium" impedance between the antenna terminals.

Correct. I'm figuring about 5k ohms. I'll experiment with the turns ratio 
later so that I can arrive at the most signal possible, but this present 
level of signal is plenty for the R-75.

>It >would also be interesting to treat the antenna as an infinitesimal 
> >vertical dipole, and not ground the bottom end. Of course, the lossy 
> >dielectric of the tree and the close proximity of ground would >probably 
>throw the balance off.

As they say: Been there; Done that! Last night I found a 2db improvement by 
using the ground rod in addition to the 30ft of return wire from the antenna 
laying on the ground. Then I cut most of the extra wire wire off and checked 
the signal with and without the ground. (BTW, I had the portable SVM in the 
woods with me so I could see the effect instantly). The increase with the 
ground rod connected was at least 6db. I'll give you a more precise number 
the next time I'm out there.

I'm thinking that there is nothing great about a true dipole in this case. 
Reception should be just a matter of probing the E-field of the LF wave as 
it passes by. The father apart the electrodes, the bigger the phase/voltage 
difference, and the stronger the signal. I'm thinking the ground at the base 
of the antenna is the best location for one of the probes since it's 
impedance to the wave has to be small.

Tonight is a new night. Can't wait to check it out!

Bill


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