In article ,
"Matthew&Wendy" wrote:

Should I put the chokes on the cables inside, or just outside the
casing?


"Telamon" wrote in
message

.com...
In article , "Matthew&Wendy"
wrote:

I like to use my computer to translate CW and record shortwave.
However, the computer throws out a lot of RFI. If I build a
Faraday cage around it, will this help? Does the cage need to be
grounded?

Matthew Plante KC2KEI Scars are the proof that man can survive his
own stupidity.

Building a Faraday cage around the computer would be a lot of work.
Most of the noise is radiated from the cabling so use ferrite
common mode chokes on the cables.

The chokes can be inside or outside the case. When placed inside or
outside the case the chokes should be near the case.

The metal of the case will stop a lot of the noise from getting out of
the the box. Most computer devices cases are either metal or plastic. If
plastic they will be impregnated with absorption material or there could
be conducting foil on the inside.

With the case preventing most of the circuits inside from radiating the
noise it can still get out through the cables going in and out of the
box. That is where the chokes on the cables will help.

When it comes to the monitors (CRT or LCD) noise can also radiate from
the viewing area. There are screens you can buy that are designed to be
both anti-glare and anti-RFI (Radio Frequency Interference) for the CRT
monitors. You just slip the screen over the front of the monitor and
attach a wire to a ground point on the chassis.

--
Telamon
Ventura, California