Uh oh, here we go again. There is a perceived risk of noise due to the dissimilar metals issue in the materials of LMR-400 (foil and braid). Having used miles of it, I've never had an issue either. I've talked with two engineers at Times about it, they claim they have never seen an issue with it. However, you will find a group of folks that swear once they replaced that piece of LMR with (insert your favorite product: heliax, RG-400, RG142, etc.) that the problem went away and the fault was that of the LMR coax. PLEASE go back and look at all the messages where we've discussed this many times rather than go through it again.unless you have some new information to shed.
Generally, due to the fact that some have asserted problems with the LMR products in full duplex/duplexer applications, why risk it. Of course, your mileage may vary. Why would you say "I know better than to use these in duplex service?" I have used LMR400 for duplex cables for years and have never had one single problem. If you do your calcalations correct for figuring the length of your cables then there should not be any problems. LMR400 is the best and then there is Heliax.
