Intro:

    New ac units were installed in buildings I and II sometime in 2011 (need exact dates). There are control units in the AC room (adjacent to the computer room in building one). There are also units (with compressors) on the roof of building I (two units Lenox) and one unit atop building II (need brand). The control units inside building 1 were put inside huffman boxes. The units on the roff are enclosed in aluminum enclosures with doors for access.
    Inside the roof aluminum unit there is what looks like a computer in a plastic enclosure (about 100 wires coming in/out). This unit is most likely the unit that communicates with the controllers down in the AC room. There is also a printed circuit board mounted in the aluminum box. Tests showed that most of the rfi comes from the "cpu" inside the roof enclosure.

Measurements:

• 28jan13: rfi coming from building 2 A/C unit using a spectrum analyzer at the unit.
  
• 24jan13: building 2 power shutdown shows rfi coming from A/C unit atop building 2.
  
• 29sep11: looking at the 1408 MHz birdie while the cabinet doors were opened,closed.
  
• 18-26 sep11: 1408 MHz rfi reported by a2010 (alfalfa).

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Shielding,leakage:

• 111001:
• The aluminum enclosure on the roof has a door with a rubber gasket.
• It should be replaced by a conductive gasket.
• You will also need to scrape the paint from where the gasket makes contact with the box and the door.
  
• It looks like there might be the start of aluminum oxidation around the edge of the door. This needs to be monitored.
• The ac power tube that enters the lower left of the box leaks the 1408 birdie. The tube may have metal in it but there is probably a rubber gasket.
• A 80 Mhz comb is also coming from the unit. We see it at 320 (327Rcvr) an 720 Mhz (800 Mhz rcvr).
  

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