If unplugging the fan alters the noise then it sounds like the fan current is somehow getting into the signal path. You also have what looks like a switching PSU in there? which is another complication.
Its a bit simplistic to say all grounds should be returned to one point but that might be a good starting point. Any ground leads that carry significant current can not be used to ground other parts of the circuit to.
Its a bit simplistic to say all grounds should be returned to one point but that might be a good starting point. Any ground leads that carry significant current can not be used to ground other parts of the circuit to.
likely someone will give evidence to the contrary but the RCA's i see in this picture seem problematic to me whether or not the case is grounded or floating...
any chance of diagramming out a schematic for all the bits and pieces so that things can be sorted out?
sometimes eliminating multiple or redundant grounds goes a long way to resolving noise problems...this could be the case here.
any chance of diagramming out a schematic for all the bits and pieces so that things can be sorted out?
sometimes eliminating multiple or redundant grounds goes a long way to resolving noise problems...this could be the case here.
