Diane-
I am not familiar with laptops but I do know most can be plugged into an
external monitor. Many people use their laptop on the road all week and when
they get home they plug it into their home sytem and transfer files etc. I
don't know if this would work as a dual monitor setup or if when you plug in
the external  it would disable the laptop screen. There are other people on
the list who can better advise you on this.
As to RFI- A quick explanation- Computers are horrific generators of rfi.
Most all electronic equipment generates RFI , some more so than others.
Internal shielding and filters on the outputs try to keep this RFI from
being radiated into the air. A prime example is a hair dryer, elect mixer or
blender. If you run one of these any where near most tv's you will see a
pattern of white lines and static on the tv. These types of equipt use
universal brush type motors which arc when they are running. The arc is
similiar to the old spark type transmitter from when radio first started.
This can be a lenthy subject depending on how much you would like to know
about it. Suggest you go back to the Ham Radio site and look around some
more or try Googling "What makes RFI"  or "Radio Frequency Interference" I
am sure you will find numerous explanations.

HTH
John Dinges

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