[sdiy] Frustrating RF Interference

[Stephen Jones]

> Ahhh I was not clear about this...
>
> I added the bead INSIDE the mixer...from the point where the
> wires entered the case, to where they are grounded on the bus PCB.

And that makes sense, because more than likely those wires aren't as
well shielded as a cable you might make yourself.  Plus, if the problem
is the unshielded wires on the inside, then trying to solve the issue
at the shielded wires would be futile.

I've got an MX9000 which is a fairly large but still small time board.
One of my input channels is blown anyway, so I need to go fix that.

> The interference in my case may have been from a carrier current
> transmitter (wireless speakers ?)in the apartment building I was  
> in. VERY
> curious, VERY annoying...

Speaking of speakers, my passive speakers (powered by a Hafler  
TA1600) don't
get much RFI put through them.  My second pair which are MS101 IIs, are
powered speakers and I do get RFI through those (still).  They're not  
grounded
and they don't have balanced jacks.  They're mainly there as just a  
second
pair of speakers for checking mixes.  The RFI for those seem to be  
coming
from a preamp (pyle pro) that I use with my turntable and some other  
'sources'.