In article , Anton Gÿsen
wrote:
Jim Lesurf wrote:

Since you have a 'wall wart' you could fit a shunt RF capacitor and
some ferrite beads to the lead from wall wart to the DAC. This would
be cheaper than buying an enclosed filter block, but requires you to
be able to solder, etc. You'd also need to know enough to choose
suitable components.

It does have a ferrite loop on it.

I was thinking of individual beads on each of the wires, followed (i.e. on
the DAC side) by an RF cap between the wires. Having just a series ferrite
increases the RF impedance and losses along the wiring, but that doesn't
always ensure good suppression. Indeed, might act as an antenna in some
situations. :-)

If the ferrite is something like a clip-on 'box' or a loop you can unthread
without damaging the wires it might be worth experimenting and seeing if
taking it off makes any difference. But if you aren't bothered by the
intereference I'd recomment not bothering if it would mean haveing to
rewire at all. If the interference is mains conveyed a filtered
distribution block will probably help, and will give you a mains switch if
you choose the right design. See something like the CPC catalogue for
examples.

Slainte,

Jim

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