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Old November 11th 06, 11:48 PM posted to rec.radio.shortwave
[email protected] r2000swler@hotmail.com is offline
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First recorded activity by RadioBanter: Jul 2006
Posts: 285
Default Follow up on Transfer Impedance


Bob wrote:
Terry -

Have you found any specific wall warts that you would consider
reasonably electrically quiet?

Thanks again, Bob


Even with wall warts that appear to be identical, the RFI varies a
great deal.
I go to the local good will store once every couple of weeks with my
trusty
DX398 and check out their constantly changing stock for quite ones.
Stay away from switch mode wall warts. They are very light weight and
are RFI demons.

I try to keep a selection on hand of the more common voltages and try
to
limit my purchases to those that are fastened with screws.

At home I have modifed nearly everything in the radio room to run from
+12V so I
only have to worry about the one big supply. It also makes operation
during power
outages easier as I have several GellCells on constant float ready to
take over
when the grid goes down.

I will try to assemble/edit down a list of usefull links and email, or
get Will to
email, them to you. The r2000swl/swler accounts are dead. Too much hate

filled spam.

What type receiver are you using?
What type antenna(s)....
What is your special interest...

It is hard to overestimate how much a good ground can improve every
situation.
"Good" is difficult to define, but in my mind it is much more then a
single
8' ground rod or a cold water pipe. A triad of three 8' ground rods
arranged in
a equalateral 12" triangle, interconnected by #8 solid copper wire is a
good
start. An alternative can be made with one 8' rod, and ~20' of soft
copper
tubing buried at lease a foot. The use of balanced antennas makes the
ground less critical. I am not a big fan of loops, but I have found
that active,
broadband dipoles, in the right places can reduce the need of a good
ground
nearly completly. And while I don't care much for loops, many first
class
DXers swear by them. Good, well balanced loops don't require much in
the
way of a ground.


Terry