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TJAN24

Modified 18:09, 5 Feb 2020 by rottmann | Page History

    Version as of 00:33, 12 Dec 2024

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    TJAN24 Correlation Report

    General information

    • Fringe test between PV and NOEMA at 3mm
    • Done with the EHT setup 4x2GHz dual-pol

    Fringes

    Baseline Band Fringes Plots Comments
    Na -Pv band1 OK No0030_b1.pdf  
    Na -Pv band2 OK No0030_b2.pdf  
    Na -Pv band3 OK No0030_b3.pdf  
    Na -Pv band4 OK No0030_b4.pdf  

    Notes

    • Email Bremer (28.1.2020) :
    ...Wenn ich Olivier richtig  verstanden habe, sollte die Richtung der R2DBE Spektren im LSB invers zu der Himmelsfrequenz laufen (da gab es mal ein Mißverständnis), im USB mit der Himmelsfrequenz, und wir sollten Signal auf 100-1700 MHz haben in dem 0-2048 MHz Band.
LO1  Frequenz war 92.101000 GHz, wir sind also 1 MHz verschoben relativ zu Pico.
Unser 1PPS Signal sollte einen mittleren Null Offset relativ zu GPS haben, ich hoffe, die Zero Crossings werden Euch nicht stören. Drift sollte sehr klein sein, unser Fit gab zero Drift. VLBI antenna war A9, auf Pad Position E03   4523999.442, 468067.530, 4460310.069 (nach Dave Graham's Skript).
Wir waren für alle 3 Scans auf der 5 MHz Referenz der Masers, genau wie für die 1.3 mm Daten. Die Quellen wurden lokal sehr gut detektiert.
    • Email Bremer (5.2.2020) :
    LSB: B1:Fsky=LO1-7000-IF_R2DBE, B2:Fsky=LO1-5000-IF_R2DBE
B1: in the R2DBE [0, 2048] MHz => on the sky [85101, 83053] MHz
B2: in the R2DBE [0, 2048] MHz => on the sky [87101, 85053] MHz
USB: B3:Fsky=LO1+5000+IF_R2DBE, B4:Fsky=LO1+7000+IF_R2DBE
B3: in the R2DBE [0, 2048] MHz => on the sky [97101, 99149] MHz
B4: in the R2DBE [0, 2048] MHz => on the sky [99101, 101149] MHz
    • Gino Tuccari (5.2.2020) :
    The 0-2G|2-4G FIRs do not flip the baseband orientation.
The baseband orientation depends on the 4-12G IF, Valon LO tuning, analog filtering.

--tjan24: in practice, oct2-4 is flipped by FIR/shift, oct0-2 is not flipped!
Also seen at Pico with spectral line.

    Basebands

    • NOEMA signal chain
    Band backend recorder sky netSB  
    b1: LSB hi r2dbe1 recorder1 (Mark6-4129); collected 83053 - 85101 lsb  
    b2: LSB_lo r2dbe2 recorder2 (Mark6-4124); collected 85053 - 87101 lsb  
    b3: USB_lo r2dbe3 recorder3 (Mark6-4130); collected 97101 - 99149 usb  
    b4: USB_hi r2dbe4 recorder4 (Mark6-4131); collected 99101 - 101149 usb  
    • Pico calculations
    1st LO 92100
B3,B4 : 1st USB : bdc1 5-7|7-9 at 99100M mid : 5-7:97052..99100 | 7-9:99100..101148
B1,B2 : 1st LSB : LO 9.048G lsb : net usb start at 83052M : oct0-2:83052-85100 | 2-4:85100-87148
    • PV signal chain
    Band backend recorder sky netSB  
    b1: LSB hi DBBC3 recorder4; collected 83052 - 85100 usb  
    b2: LSB_lo DBBC3 recorder3, as-is 85100 - 87148 lsb  
    b3: USB_lo r2dbe2 recorder2; collected 97052 - 99100 lsb  
    b4: USB_hi r2dbe1 recorder1; collected 99100 - 101148 usb  

    Issues

    • Data weights for PV-RR are reduced. On the 4-module set containing "hand-carry" copies of the other 4-set modules, copied modules have 6 out of the 16 fragment files per scan missing. Apparantly the copy procedure was incomplete. Affects bands 1, 3, and 4.