"The use of aluminum instead of ferrous material (steel) for chassis,
separate compartments, etc. is probably one of the greatest reasons TT
rigs are more RFI prone."
As I understand it, the principle involved with RF-shielding as opposed
to shielding for AC power and audio magnetic fields, is that with RF it
works by using a good electrical conductor which then produces an
induced reversed-polarity field, which cancels the field which generated
it in the first place. Therefore, aluminum or copper or silver all
shield RF more effectively than does steel or iron.
73, Roy K6XK
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