Everyone is giving you some excellent advice that is beyond my
ability.
But having been a ham for over 50 yrs I have learned that a lot of
the
noise generated locally is from two places, power lines, and believe
it
or not , the biggest one is door-bell transformers in attics.
Power line problems are the easy for the most part and usually
within
one mile of your qth shack.
Take a small am portable radio and a large hand held hammer and start
walking
around the neighborhood. Tune off of a local station so you can hear
better.
HIt each pole that you come too with the hammer, any change heard
indicates
something is amiss. I have located bad ground connections in the guy
wires
from the pole at so many, I can not recall the number.
If you find a pole with bad noise, don't do anything yourself. Call
the local
power company,( sometimes it takes several calls until they start
helping),
let them listen to the noise in your rcvr and they show them what you
have
found. All power companies are suppose to have equipment that will be
a
great deal better than your am radio.
In either event, you will need the power company to help you!!!!!!

Door bell transformers are the worse. They are continually connect to
the power
supply 120 line. Most of the time in an attic, and don't be shocked to
find that
they are under the insulation up there. They are especially a fire
hazard to the
home owner, so most folks will be happy to know about them.
The only way that you can surely go down to the right house is with
the power
company man. The am radio buzz and the equipment they have should put
you in a nearby homeplace. The power meter must be removed to pin it
down.
If the meter is removed and the interference stops and upon re-
insertion starts
again, you are at one source.
Let the power company do the talking and get permission to check the
fuses boxes
first to see if it can be narrowed down to something else. If this
shows up when
the fuse is open and the door bell button is pushed and nothing
happens , well
you have one.

I found so many, I brought me several and asked the power man to
install it
up on the roof joints. Air can the circulate and relieve the heat
issue.
Everyone done this way has never gone bad again.
Hope this helps some.
73
John K4ZYF,SC