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lbaops:tidnotes:dasconfig [2015/12/18 16:39] (current)
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 +====== DAS Configuration ======
 +The Wiki should document the correct DAS configuration to use for each experiment (click on the "​telescope"​ link next to the config name). There are two DAS configurations commonly used for VLBI at Tid.
 +===== =====
 +This takes two 32 MHz bands and produces four 16 MHz data
 +streams. Data centred at 160 MHz into IFP#1 will be split into two
 +bands: 144->160 MHz and 160->176 MHz. Similarly for IFP#2.
 +So for example, [[lbaops:​lbamar2007:​v209a | V209a]] requires:
 +  *  2269 - 2285 MHz RCP and 2285 - 2301 MHz RCP for IFP#1 and,
 +  *  2269 - 2285 MHz LCP and 2285 - 2301 MHz LCP for IFP#2
 +The [[lbaops:​tidnotes:​freqsetup | frequency setup]] would be such that
 +RCP in IF#1 would be mixed with a 2nd LO of 445 MHz to put the sky
 +frequency of 2285 MHz RCP at 160 MHz (flipped) and IF#2 would have the
 +LCP signal and the same 2nd LO frequency.
 +===== =====
 +This takes two 16 MHz bands and produces two 16 MHz bands. Data
 +centred at 160 MHz into IFP#1 will be digitised into a single band
 +covering 152 - 168 MHz. Similarly for IFP#2.
 +===== =====
 +This digitises two 64 MHz bands centred at 160 MHz. When loaded into
 +the DAS it will not flip
 +the bands, even though the profile specifically says it should. To
 +flip the band you must do it manually by going to pages 1 and 4 of the
 +setup screens and changing address 30 to 1.
 +Note that the DAS to VSIB cabling needs adjusting for this mode. See
 +[[lbaops:​onedasat512|these notes]].
lbaops/tidnotes/dasconfig.txt · Last modified: 2015/12/18 16:39 (external edit)