summary: power supply and chassis

[Haible Juergen]

	>2. Enclosure
	>Use a metal enclosure for your device. This will damp rf
interference.
	>Try to have as few holes in the enclosure as possible. Otherwise
	>rf signals may sneak in. 

While this is definitely a good choice, I'd say it's not the only one.
I have quite some of my circuits in wooden enclosures, and I'm not
plagued with RF interference at all. (But then I try to take a lot of care
about the circuit layout - I won't have sensitive high impedance parts
go over long wires for instance.)
I'd say a metal enclosure is not always necessary, but *if* you have
a metal enclosure, then grounding it (with a C at least) is a must.

JH.