> Hi, John, > > That's very interesting. How does this compare with a laptop or other PC? > Why was it tested with the lid off? Is that how it will be deployed?
Laptops and other PCs are a different kettle of fish altogether. They have a wide range of emissions, and most of them have emission about 40 dB above the ITU limits at the distance of the lab here. It was tested with the lid off because that's how it was given to the tester. The standard enclosure is not in any way RFI tight, and would likely have had no effect on the emissions, unless we sealed it up with copper tape. We plan to package them better than they currently are packaged, for sure, likely either packaging them individually in the SA MeerKAT custom enclosure, or in a common shielded rack. John > > Thanks, > Dave > > On Sep 6, 2011, at 1:14 PM, John Ford wrote: > >> Hi all. >> >> We tested a ROACH and and 2 ADC boards (3 GS/s boards) in our anechoic >> chamber to get a feel for the emissions to expect from the new >> spectrometer being designed. The ADC clock was running at 500 MHz. >> >> The results of the test are attached. In summary, to use these at our >> site, we will have to have a supplementary shielded enclosure in >> addition >> to our shielded equipment room. >> >> Thanks to Carla Beaudet at NRAO for the testing. >> >> (If anyone has anything they'd like us to test in the chamber, let me >> know.) >> >> John<RoachBoardsAnechoicChamberRFITestReport.pdf> > >
