PV Setup and verification

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    Version as of 21:02, 28 Apr 2024

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    General

    1st LO = 92100 MHz

    Total LO (DBBC2) = 85500 MHz

    Total LO (DBBC3) = 84100 MHz (UI band)

    DBBC2

    Firmware

    • Installed new firmware ddc v107 beta3

    •  

      Finished DBBC3 calibration

    Tone injection

    • noise + tone injected into pins 4 of board A and B
    • verified if power levels (attenuation 23)
    • set vsi_clk=128
    • set dbbcform=astro
    tone (MHz) IF A IFB  
    528 OK OK  
    592 OK OK  
    656 Missing OK  
    720 OK OK  
    784 Missing OK  
    848 OK OK  
    912 Missing OK  
    976 OK OK  

    Bandpass plot shows that LSB of BBC2, BBC3, BBC4 are corrupted

    Cleaned connectors of VSI1 cable connectin DDBC2 to Fila10G. No change. As a test have re-configured Fila10G to use vsi2 instead of vsi1 which has not changed the result. This implies that it is not a transmission problem over the VSI cables.

    Update: Due to a power failure on March 3rd the VLBI equipment was brought down (DBBC2, Fila10G). After restarting all equipment the bandpass now looks good and lines are verified in all subbands.

    DBBC3

    Firmware installation

    • installed DDC_V_123

    IF-Setup

    IF1 (E0VLI, LCP)  => CoreBoardA => recorder2 eth3 => Module MPI%8005 (slot 1)

    IF3 (E0HLI, RCP) => CoreBoardB => recorder2 eth35 => Module MPI%8008 (slot 2)

    System verification

    • run setupDBBC3_DDC_V.py

    Tone injection

    Tone was injected into the beam at 86.242GHz

    Line appeared in both polarizations in the baseband at 3190 MHz.

    Recording

    Recording was done on recorder2 onto 2 modules.

     

    LCP RCP
    dbbc3_lcp.png dbbc3_rcp.png