Any luck finding your issue with the noise. Also I was going to suggest that you look into a good ground system and also a good surge arrestor before your coax enters the radio shack or whatever room you are using. Read up on how commercial cell tower me are built and you’ll get a good idea of what is really needed to make a solid base station setup. Just some food for thought. I been retired for a couple years and now I certify aircraft instrumentation. Cool stuff. But I miss my old job as a cell site tech and installer. At any rate, keep is updated on how and if you got your noise issue resolved. Good day