[TowerTalk] CAT 5 for SteppIR Remote Driver?

[Jim Brown]

On 7/25/2012 1:15 PM, Steve Jones wrote:
> Do I need a separate CAT 5 cable for each antenna's Remote Driver, or can a
> single CAT 5's four pairs handle two SteppIR antennas?

CAT5 is great cable, and has great noise (and RF) immunity if you use a 
pair for each signalling (or control) circuit, BUT it's pretty small 
gauge, so the loop resistance can be high.  Study what SteppIR says 
about the loop resistance of that control line and do the Ohm's Law 
arithmetic. If they define resistance by a certain length of a given 
wire gauge, you can make use of the fact that three wire gauges is half 
(or double) the resistance.

Another trick -- if you use a pair per circuit and tie all the returns 
together on both ends, they're all in parallel, which for a lot of 
circuits is equivalent to cutting the loop resistance nearly in half.

73, Jim K9YC