>I'm planning to put up several beverages on a farm that has cattle grazing
>all over it. For obvious reasons gradually sloping the beverages to ground
>level at both ends would require quite a bit of extra fencing to keep the
>cows away from the wire. In ON4UN's book (2nd edition) he shows a system
>(Fig. 7-17) of a capacitor and 10 ft length of RG-62 to ground one end of a
>two-wire beverage.
>
// I used to run a 3-wavelength 8-ft. high beverage for 80m longpath
into N. Europe. I found that there was a change in ground conductivity
depending on rainfall. To be able to adjust the terminating resistance
remotely, I put a series string of fwd biased Si diodes in series with a
fixed resistor and adjusted the DC current through the beverage wire
until I got the deepest null on signals off the back. When the diodes
were reverse biased, the beverage was bi-directional. note: the fwd
biased resistance of a Si junction is approx. 30/current in mA -- i.e.
2mA makes for 30/2 = 15-ohms per diode.
> ... ...
cheers, Fritz
- R. L. Measures, 805.386.3734,AG6K, www.vcnet.com/measures.
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