View Single Post
  #35   Report Post  
Old September 19th 11, 06:48 PM posted to rec.radio.amateur.antenna
dave dave is offline
external usenet poster
 
First recorded activity by RadioBanter: Jan 2009
Posts: 5,185
Default duplexers, antennas, repeaters

On Sun, 11 Sep 2011 16:05:44 -0700, Jeff Liebermann wrote:

On 10 Sep 2011 18:27:58 GMT, dave wrote:

Cell sites are a different animal . We were talking about 2-way,
point-to-point, VHF/UHF broadcast type sites.


Perhaps you didn't notice but several of the examples of PIM and rotten
coax induced intermod were for non-cellular systems. The problems are
much the same with any service type. If you have moderate TX power,
magnetic materials in the connectors, and sensitive receivers, PIM might
be a concern.


It's still a math problem. You can predict intermod products from known
frequencies whether the non-linear device is active or passive.