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07 July

Modified 17:08, 1 Jul 2011 by horneff | Page History
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    1. 1. 2011 July 1
            1. 1.1.1.1.1. 1) Check problematic RCU

    Version as of 19:59, 3 Nov 2024

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    2011 July 1

    K. Schlich and A. Horneffer did the following:

    1) Check problematic RCU

    As seen on June 30the tile 64/65 was not working properly, because RCU 64 did not provide the neccessary power.

    We tested the impedance of the cables to tile 64/65 and 70/71:

    64: 200 kOhm, 65: 21 kOhm, 70: 240 kOhm, 71: 24 kOhm

    On removing RCU 65, the half-lit LED on RCU 64 went off. Measuring the output voltage on then gave the correct results, and the tile 64/65 worked. We also replaced the RCU 65 with a new board, for this we had to remove the current limiting NTC/varistor(?) on the new RCU module to place and connect the HBA modem.

    All tests afterward (modemtest and spectrum check with rspctl) were successfull afterward.

    RCU modules now in place:

    64: -> 10638002067

    65: -> 10638002051

    RCUs to return:

    broken with high ADC noise: 10638001026

    were at some point at position 64 and did not provide power to the HBA tile: 10638002049, 10638002087, 10638002001

    2)