Looking at an image the quadrants are arranged as follows:

• quadrant 1 = top left
• quadrant 2 = top right
• quadrant 3 = bottom left
• quadrant 4 = bottom right

There will be two DAQ modules associated with each quadrant (8 outputs per quadrant with each DAQ module processing 4 outputs each).

• quadrant 1 = DAQ 1 & 2
• quadrant 2 = DAQ 3 & 4
• quadrant 3 = DAQ 5 & 6
• quadrant 4 = DAQ 7 & 8

If you are looking at the DAQ rack..with the LEDS facing you…the Clk/Bias module will be to your left. The DAQ modules should then be numbered 1-8 left to right. You can check this be looking at the labels on the orange fibre optics cable. Cable 1 should be going to DAQ module 1, cable 2 to DAQ module 2 etc.

As a double check…the array output cables, 2 of (the ones that come out of the cryostat and split into 4) are labelled 1-4 and 5-8. So the array output cable 1 should be going in one side of the DAQ 1 module with the orange fibre optic cable 1 coming out the other side of the module and similarily for modules 2 – 8.

If you are suspecting pickup from the fans then you can narrow it down even further as the readout topology is in blocks of 4 reading from the corner into the centre.

So taking quadrant 1 as an example, the first 4 columns (l-r_) would be outputs fed into DAQ Module 1 the next 4 would be outputs fed into DAQ Module 2. For quadrant 2, the first 4 columns (r-l) would be DAQ module 3 and the next 4 would be DAQ Module 4. So if the structure is only in one set of four outputs you can check the fans on that module.

To check whether it is the DAQ modules themselves that are noisy and not the outputs from the array you can short the DAQ inputs and check the S/C noise. This can be done automatically by setting setInput 0 in all the daqslave windows.

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