jan16: 327 rfi from the turret control box

27jan16



Introduction (top)

    On 27jan16 Felix and i  found strong rfi coming from the turret control cabinet (huffman box in the gregorian receiver room). Checking the rfi gasket on the inside of the huffman box door, we found high impedance  along the gasket (this was the old gasket with rubber impregnated with silver.. we've had problems before with this gasket material oxidizing..).  Willie and Osvaldo replaced the gasket with a wire mesh gasket.
    On 28jan16 we tested the rfi shielding of the cabinet.

    The setup was:

The datataking procedure was:


The dynamic spectra:

    The dynamic spectra were made by:

freq range of image
300-308
307-315
314-322
321-329
328-336
335-343
342-350


Some comments on the rfi:

Comparing cabinet Door closed with the cabinet power off:

    For each band i averaged when the power was all the way on, and when the power was on and the door was closed.. i tried to leave out the transition periods.

The plots show the rfi when the cabinet was PwredOn/Closed and PwredOff/open (.ps) (.pdf)

I then plotted the rfi peaks coming from the turret cabinet (.ps) (.pdf)

Summary:

processing: x101/160128/rfiturret.pro

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