Thanks guys for all the advice & offers for cable. There is Belden 1808A,
Twinax & several rip coax cables that will work. These are quite expensive
compared to just using two RG-58's for the balanced, shielded feedline.
Making the two lines of the same coax and cutting each the same length
should be the only requirements for exposing both center conductors equally
to the noise and unwanted signals.
Per information received, there is no need to twist the two coax cables
together. The two coax shields are bonded together at both ends, so that
whatever signals are picked up on the outsides of both shields, end up going
around the ends of the coaxes, and inside the shields, where they induct
equally into both center conductors. Since the center conductors must each
be excited at a phase or amplitude difference, for the receiver to detect,
the unwanted sigs of same phase & current, null each other out. This is a
neat shielded feed system that wants to work!
I will proceed with the single, choked coax leadin for now, and try the dual
coax balanced line after getting things working. Then I hope to make a
report to the reflector of any advantages using the dual coax, shielded,
balanced system.
73, Doug / NX4D
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