[RFI] Computer RFI problem

[eedwards@oppd.com (EDWARDS, EDDIE J)]

> -----Original Message-----
> From: Rob Atkinson, K5UJ 
> The excerpted description above could easily refer to a feedline parallel to 
> the radiating element although I have no idea why anyone would feed an 
> antenna in that fashion.  
> 
        Rob, 

        This is exactly the way we have mounted 7 out of 9 of our 800 Mhz 
colinear verticals on our 500 foot towers here in Nebraska.  The reason?  
Lightning protection/suppression.  

        Before I came along and installed Polyphaser suppression on everything, 
the previous engr decided one way to cut down on blown-up antennas and damaged 
equipment was to invert all of our colinears that are at the top of each tower. 
 The problem is that he also added ground strap kits (to the shields) on all 
cabling and replaced the Decibel antennas with newer Scalas at the same time.  
Inside damage was drastically reduced (due to grd kits or inversion?) and the 
new Scalas have held up very well.  So I cannot tell which change helped the 
most, but I suspect we're not getting direct strikes as easily as before, and 
the ground straps help quite a bit as well.

        Haven't noticed any computer noise, but then the antenna is 500' away 
so local CPU/monitor noises probably can't make the long trip.  ;^)

        73,
        de ed -K0iL