One of the big questions is will the diodes in a radio power supply
cause cross modulation. It doesn't happen all that often,
but when it does it is a nightmare. I prefferred to take my time and
do one supply right. I actually have 2, it is nice to have a spare,
just in case. On the R2000's and my Pro2004, the internal supply
always adds a little frying noise. Most of the time the residual
"background" noise swamps that minor noise.
But on nights when the band is quite, that little bit of noise is very
frustrating. I have used salvaged ferrite cores on the power, audio,
video, and RF cables going to EVERY piece of equipment
in our house. I took a bunch of GE MOVs, the kind that plug into the
AC outlet and have a female socket, added a 0.1uF cap between
both "hot" and "nuetral" to ground, and found it to help quiten the
house way down. While the nuetral and ground are connected in the
breaker box, it did help a great deal to quite the TV, alarm clock,
and microwave down. The microwave is still nasty, but my wife doesn't
like it or use it that much. I was goong to add them to the duplex
outlets
but the local electrical inspector nixed that idea. Getting all three
PCs,
my wifes, mine and the dedicated MP3 "juke box" PC, was the biggest
heartache. I had to put multiple ferrite cores on every cable that had
anything
to do with the PCs.
For my car Iused an unused power tap in the main fuse box, and routed
the wire through the firewall to a Cannon style 4pin female XLR. That
type
connector is often found on commercial TV field gear, so I decided to
standardise so I can hook my 12V devices up to the supplies at work.
I used a "bunch" of ferrite cores in a failed attempt to quiten my 1991
Civic.
It is much better then it was before, but it is still way to noisy to
even think
about adding a SW to use while driving. Thank God for MP3 players. I
get
to choose what music I listen to, with no DJs, ads or idiots.

Terry