Jacques,
> Rys want to use this twested military telephone line for a
> two wire beverage, I agree Jim, on one direction the impedance
> between the two wires and the ground will be more or less the
> same as with any other type of wire but Rys want to use also
> the 150 ohms twisted line to return the signal from the far
> end to make a reversible Beverege.
Other than the possible impedance change with weather that W8JI
warns about, you should not have any problem using the 150 Ohm
line for a reversible beverage as long as you adjust the
transformers for the new impedance ratios.
If you look at ON4UN's book, figure 7-23 on page 7-22, it will
be necessary to adjust n1:n2 of T5a to a ratio of 1:1.75 (or
the square root of 450/150). You will also want to adjust the
ratio of n1:n2 in T4 to 1.75:1 (in this case the square root
of 150/50).
In a normal two wire Beverege, T5A would have a ratio of about
1:1 (450:450) and T4 would have a ratio of 3:1 (Square root of
450/50).
The transformation ratio in T1 will not change with the impedance
of the two wire line as it is looking at "Beverage mode" to
receive feedline (450:50).
73,
... Joe, K4IK
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