[TowerTalk] Rapid-Deployment Beverage?

[N1BUG]

> It doesn't work that way.  You need two feed lines, each going to
> opposite ends, each end having both a transformer and resistor, and
> relays that switch them in or out to flip the direction.

Not necessarily. I have several bidirectional Beverages made from WD1A 
field phone wire. That stuff is like zip cord with a light twist. I have 
just one feedline running to one end of each Beverage. At the far end is 
a reflection transformer rather than resistor tor termination. At the 
feed end, a DPDT relay is used to select direction. In the "reverse" 
direction, the incoming signal is fed into the far end of the twisted 
pair in differential mode by means of the reflection transformer, where 
it travels back to the feed end using the Beverage as twisted pair 
transmission line. Voltage to power the direction switching relay is fed 
over the coax. By the way, these work equally well if not better fed 
somewhere along the length of the Beverage. The entire length is still 
used in both directions, so there is no performance loss. However this 
requires a different circuit at the feed point and two reflection 
transformers.

I got the basic idea from here:

<http://win.i1wqrlinkradio.com/archive/OH2BEN_Reversible_Beverage_Array-20-10-2007_04d.pdf>

I made some changes including feeding relay power over the coax and the 
center feed, but I have never found time time to properly document my 
variation.

73,
Paul N1BUG