At 1/3/2010 11:11, you wrote:
>Yes, it was resolved at a lot of commercial sites by not allowing it to be >used ;-) For me, the "resolution" came from a Times Microwave sales rep. who admitted that LMR-400 is not appropriate for duplex use. Having said that, you can get away with using it in situations such as temporary/portable repeater installations provided the connectors are installed properly & the feedline is not used near the antenna, where RF can couple to the outer braided shield. In no circumstances would I ever use it at a shared comm. site. >Usually after a bit of time, the cable will start to become a source of >noise as the two dissimilar metals start to react with each other. There >are many documented cases of this problem. Search this group's messages >and you'll see this has been discussed over and over. It comes up about >every other week. BTW, they don't need to be dissemilar metals. I once confirmed a 100% copper braided RG-213 jumper as a PIM source. I only use silver-plated braided coax beyond the duplexer from now on. Bob NO6B
