Hi Don
>>Because it's amplitude is time varying, aluminum or any other metal can
>>provide an effective shield based on the skin effect principal (you just have
>>to factor in the resistivity of the material and operating frequency to
>>determine how thick the material must be to become an effective shield).<<
I think my preamplifier does not agree much with that. My PC LCD monitor screen
was causing several noises I could hear on 160m and actually I could see them
on the SDR waterfall. When I put the preamp inside a galvanized steel box all
that crap coming from my PC and PC LCD monitor just vanished, the box was open
in one side and not grounded.
The preamp was inside a TIM PLATE BOX used for EME shield with feedthrough
capacitor and chokes, but the steel galvanized box improved the shield a lot.
1.8 MHz is quite a different band.
73’s
JC
N4IS
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