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operations:documentation:lba_dbbc_config [2013/03/21 04:40]
Jim Lovell created
operations:documentation:lba_dbbc_config [2013/03/28 05:35] (current)
Jim Lovell
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 There are two steps to setting up the DBBC - the first is the working out which IFs are needed and then setting the channels appropriately. The setups below list the most common setups and how to get them working. Specific examples from previous experiments are shown where possible. These should work for 16 MHz bandwidth observations with either 4 or 8 channels. Anything different from this needs much more work... There are two steps to setting up the DBBC - the first is the working out which IFs are needed and then setting the channels appropriately. The setups below list the most common setups and how to get them working. Specific examples from previous experiments are shown where possible. These should work for 16 MHz bandwidth observations with either 4 or 8 channels. Anything different from this needs much more work...
 +
 +In general though, DRUDG should have calculated the IF frequencies correctly. You can check by comparing the with the frequencies on the LBA wiki and using LOs of 1900 MHz for S-band and 8600 MHz for X-band.
 +
 +See these notes on [[hardware:​dbbc.routing|how signals are routed through a DBBC]] for some background info before reading further.
 +
  
 ===== X-band, single polarisation ===== ===== X-band, single polarisation =====
  
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequenciesStart by checking ​the listed frequencies of each channel ​on the ATNF WikiIn the corresponding entry in your experiment'​s ​config file change ​the frequency to (lower ​band edge-7600). Using [[http://​www.atnf.csiro.au/​vlbi/​wiki/​index.php?​n=LBAApr2012.V271K|v271k]] as an examplechannel ​1's lower band edge is 8200 MHz. The first line in the @@dbbc_config_file_v271k.txt@@ is then @@1 dbbc2.bit 600.00 16@@Repeat for all needed channels and leave unused channels alone+As an example, here's how V252ai has it's frequencies set up according to the LBA wiki: 
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v271k.txt@@ + 
-* %red%Reconfigure ​the DBBC with @@reconfig@@ +{{:​operations:​documentation:​screenshot_28_03_13_3_05_pm.png|V252ai frequency setup}} 
-* %red%Use the @@DBBC Client@@ ​to send the command @@dbbcform=geo@@ + 
-* %red%Set up the IF inputs. I've assumed that the observing frequencies for X-band ​are between 8112 and 8624 MHz which is normal for the LBA.  +Running ''​drudg''​ on the VEX file produces ​the following IF setup for Ke: 
-** %red%If using XRCPsend these commands:\\ +<​code>​ 
-%red%@@dbbcifa=1,agc,1@@\\ +define ​ ifd01         ​00000000000x ​            
-%red%@@dbbcifb=4,agc,1@@\\ +ifa=1,​agc,​1 
-%red%@@pps_sync@@ +ifb=4,​agc,​1 
-**%red%If using XLCPsend these commands:\\ +lo= 
-%red%@@dbbcifa=2,agc,1@@\\ +lo=loa,7600.00,​usb,​rcp,​off 
-%red%@@dbbcifb=1,agc,1@@\\ +lo=lob,​7600.00,​usb,​rcp,​off 
-%red%@@pps_sync@@ +enddef 
-* %red%Confirm ​that the crossover switches ​are in the direct position. It's easiest ​to do this by starting up system monitorConnect to ops4 with @@shh -X observer@ops4@@ ​and run @@monitor_system.pl@@. Select ​the relevant telescope & check the settings of the "Cross-over switches"​ +</​code>​ 
-* Check the mk5b_mode line in the @@/usr2/​proc/​v271kke.prc@@ fileFor channels only, it should ​read as @@mk5b_mode=ext,​0x000000FF,0@@ while for 8 it should ​be @@mk5b_mode=ext,​0x0000FFFF,1@@.+ 
 +As the notes on [[hardware:​dbbc.routing|how signals are routed through a DBBC]] describe, we only need one CoMo as there'​s ​a common input IF and all frequencies are in the band of Filter 1 (512 1024 MHz). So we can drop ''​ifb''​ and ''​lo=lob...''​The input IF is X-band RCP which in input 1 and we want automatic gain controlThe input power level for Ke in CoMo A [[operations:​currentissues|should be 38000]]. So ''​ifd01''​ should be edited to look like this: 
 + 
 +<​code>​ 
 +define ​ ifd01         ​13073035822x 
 +ifa=1,agc,1,38000 
 +lo= 
 +lo=loa,​7600.00,​usb,​rcp,​off 
 +enddef 
 +</​code>​ 
 + 
 +Drudg produced a ''​dbbc01d''​ procedure that looked like this: 
 + 
 +<​code>​ 
 +define ​ dbbc01d ​      ​00000000000x ​            
 +bbc02=809.00,​a,​16.00 
 +bbc04=825.00,​a,​16.00 
 +bbc06=841.00,​b,​16.00 
 +bbc08=857.00,​b,​16.00 
 +enddef 
 +</​code>​ 
 + 
 +The LO frequencies are correct but we want to use BBCs 01 to 04 and CoMo A. So the revised version looks like this: 
 + 
 +<​code>​ 
 +define ​ dbbc01d ​      ​13073035822x 
 +bbc01=809.00,a,16.00 
 +bbc02=825.00,a,16.00 
 +bbc03=841.00,a,16.00 
 +bbc04=857.00,a,16.00 
 +enddef 
 +</​code>​ 
 + 
 +Lastly, in ''​setup01'' ​the mark5 mode needs checking. We start with  
 +<​code>​ 
 +mk5b_mode=ext,​0x0000CCCC,​0 
 +</​code>​ 
 + 
 +However, we want to pass through all bits from the first 4 BBCs, so it needs to be changed to this: 
 + 
 +<​code>​ 
 +mk5b_mode=ext,​0x000000ff,​1 
 +</​code>​ 
 + 
 +===== X-band, dual polarisation ===== 
 + 
 +As an example, here's how V465b has it's frequencies set up according to the LBA wiki: 
 + 
 +{{:​operations:​documentation:​screenshot_28_03_13_3_32_pm.png|V465b frequency setup}} 
 + 
 +Running ''​drudg''​ on the VEX file produces the following IF setup for Ke (note you may get some warning messagesjust persist and produce the files anyway)
 + 
 +<​code>​ 
 +define ​ ifd01         ​00000000000x ​            
 +ifa=1,agc,1 
 +ifb=4,agc,1 
 +lo= 
 +lo=loa,7600.00,​usb,​rcp,​off 
 +lo=lob,​7600.00,​usb,​rcp,​off 
 +enddef 
 +</​code>​ 
 + 
 +As the notes on [[hardware:dbbc.routing|how signals are routed through a DBBC]] describe, we need two CoMos, one for X RCP and one for X LCP. The first four BBCs will need to be one polarisation (RCP) and the second four (from CoMo B) LCP. A note to the correlator and whoever is running fringe checks should be sent. 
 +The input IF for CoMo A is X-band RCP which in input 1, and for CoMo B X LCP is on input 1, and we want automatic gain control. The input power level for Ke in CoMos A and B [[operations:​currentissues|should be 38000 and 33000]] respectively. Lastly, we might as well make the ''​lo''​ settings correct (although they don't actually do anything to the DBBC). So ''​ifd01''​ should be edited to look like this: 
 + 
 +<​code>​ 
 +define ​ ifd01         ​13075124605x ​            
 +ifa=1,agc,1,38000 
 +ifb=1,agc,1,33000 
 +lo= 
 +lo=loa,​7600.00,​usb,​rcp,​off 
 +lo=lob,​7600.00,​usb,​lcp,​off 
 +enddef 
 + 
 +</​code>​ 
 + 
 +Drudg produced a ''​dbbc01d''​ procedure ​that looked like this: 
 + 
 +<​code>​ 
 +define ​ dbbc01d ​      ​00000000000x ​            
 +bbc02=793.00,​a,​16.00 
 +bbc04=809.00,​a,​16.00 
 +bbc06=825.00,​b,​16.00 
 +bbc08=841.00,​b,​16.00 
 +bbc01=793.00,​a,​16.00 
 +bbc03=809.00,​a,​16.00 
 +bbc05=825.00,​b,​16.00 
 +bbc07=841.00,​b,​16.00 
 +enddef 
 +</​code>​ 
 + 
 +The LO frequencies ​are correct but we want to use BBCs 01 to 04 and CoMo A for the RCP frequencies and BBCs 05 to 07 and CoMo B for LCP. So the revised version looks like this
 + 
 +<​code>​ 
 +define ​ dbbc01d ​      ​13075124605x ​            
 +bbc01=793.00,​a,16.00 
 +bbc02=809.00,​a,​16.00 
 +bbc03=825.00,​a,​16.00 
 +bbc04=841.00,​a,​16.00 
 +bbc05=793.00,​b,​16.00 
 +bbc06=809.00,​b,​16.00 
 +bbc07=825.00,​b,​16.00 
 +bbc08=841.00,​b,​16.00 
 +enddef 
 +</​code>​ 
 + 
 +Lastly, in ''​setup01''​ the mark5 mode needs checking. We start with  
 +<​code>​ 
 +mk5b_mode=ext,​0x0000FFFF,​1 
 +</​code>​ 
 + 
 +This is correct in this case as we haven'​t changed which BBCs we're passing through, just their frequency ​and polarisation assignments. 
 + 
 +===== S-band, single polarisation ===== 
 +The setup here is essentially ​the same as for X-band single polarisation except ​the [[hardware:​dbbc.routing|IF inputs]] and LO frequencies will differ. 
 + 
 + 
 + 
 +===== S-band, dual polarisation ===== 
 + 
 +In this case the [[hardware:​dbbc.routing|IF inputs]] setup dictates that you will have S-band LCP through CoMo A input 4, and S-band RCP through CoMo C, input 2. Consequently,​ ''​ifd01''​ will need to look like this (for Ke): 
 + 
 +<​code>​ 
 +define ​ ifd01         ​13075124605x ​            
 +ifa=4,​agc,​2,​38000 
 +ifc=2,​agc,​2,​36000 
 +lo= 
 +lo=loa,​1900.00,​usb,​lcp,​off 
 +lo=lob,​1900.00,​usb,​rcp,​off 
 +enddef 
 +</code> 
 + 
 +As BBCs 1 - 4 are assigned to CoMo A, 5 - 8 to B, 9 - 12 to C and 13 - 16 to D, you want to set up BBCs 01 - 04 for LCP and 09 - 12 for RCPe.g. 
 + 
 +<​code>​ 
 +define ​ dbbc01d ​      ​13075124605x ​            
 +bbc01=300.00,​a,​16.00 
 +bbc02=316.00,​a,​16.00 
 +bbc03=332.00,​a,​16.00 
 +bbc04=348.00,​a,​16.00 
 +bbc09=300.00,​c,​16.00 
 +bbc10=316.00,​c,​16.00 
 +bbc11=332.00,​c,​16.00 
 +bbc12=348.00,​c,​16.00 
 +enddef 
 +</​code>​ 
 + 
 +The Mark5 mode needs to pass though BBCs 1-and 9 - 12so it should ​look like this: 
 +<​code>​ 
 +mk5b_mode=ext,​0x0FF000FF,
 +</​code>​ 
 + 
 +Note for a 4-channel observation you would only need to set BBCs 1,2,9 and 10 and the Mark5 mode would be 
 +<​code>​ 
 +mk5b_mode=ext,​0x00F0000F,1 
 +</​code>​
  
-!!!X-band, dual polarisation ​ 
-* Create a new configuration file in @@C:​\DBBC_CONF@@ of dbbcke if needed. If the experiment shares a configuration with a previous experiment (same frequencies,​ polarisations,​ channel order) then you should be able to use that. Otherwise, read on.  
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequencies. Put all of the channels at one polarisation in lines 1-4 and have lines 5-8 for the other polarisation. If the schedule shows the channels as alternating between RCP and LCP, tell the LBA chat (Cormac and Chris by email) that the recorded channel ordering will be different. 
-** Start by checking the listed frequencies of each channel on the ATNF Wiki. In the corresponding entry in your experiment'​s config file change the frequency to (lower band edge-7600). As an example, if channel 1's lower band edge is 8200 MHz then the first line in the @@dbbc_config_file_v999a.txt@@ is then @@1 dbbc2.bit 600.00 16@@. Repeat for all needed channels and leave unused channels alone. 
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v999a.txt@@ 
-* %red%Reconfigure the DBBC with @@reconfig@@ 
-* %red%Use the @@DBBC Client@@ to send the command @@dbbcform=geo@@ 
-* %red% up the IF inputs. I've assumed that the observing frequencies for X-band are between 8112 and 8624 MHz which is normal for the LBA. 
-** %red%If using XRCP, XLCP, send these commands:\\ 
-%red%@@dbbcifa=1,​agc,​1@@\\ 
-%red%@@dbbcifb=1,​agc,​1@@\\ 
-%red%@@pps_sync@@ 
-**%red%If using XLCP, XRCP send these commands:\\ 
-%red%@@dbbcifa=2,​agc,​1@@\\ 
-%red%@@dbbcifb=4,​agc,​1@@\\ 
-%red%@@pps_sync@@ 
-* %red%Confirm that the crossover switches are in the direct position. It's easiest to do this by starting up a system monitor. Connect to ops4 with @@shh -X observer@ops4@@ and run @@monitor_system.pl@@. Select the relevant telescope & check the settings of the "​Cross-over switches"​ 
-* Check the mk5b_mode line in the @@/​usr2/​proc/​v999ake.prc@@ file. For 4 channels only, it should read as @@mk5b_mode=ext,​0x000000FF,​0@@ while for 8 it should be @@mk5b_mode=ext,​0x0000FFFF,​1@@. 
  
-!!!S-band, single polarisation +===== S/X-band, single polarisation ===== 
-* Create a new configuration file in @@C:​\DBBC_CONF@@ of dbbcke if needed. If the experiment shares a configuration with a previous experiment (same frequencies,​ polarisations,​ channel order) then you should be able to use that. Otherwise, read on.  +This setup is not dissimilar from S-band ​dual polarisation ​aboveexcept CoMo A would be used for X-band.
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequencies. Start by checking the listed frequencies of each channel on the ATNF Wiki. In the corresponding entry in your experiment'​s config file change the frequency to (lower band edge-1900). As an example, channel 1's lower band edge is 2209 MHz then the first line in the @@dbbc_config_file_v999a.txt@@ is then @@1 dbbc2.bit 309.00 16@@. Repeat for all needed channels and leave unused channels alone. +
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v999a.txt@@ +
-* %red%Reconfigure the DBBC with @@reconfig@@ +
-* %red%Use the @@DBBC Client@@ to send the command @@dbbcform=geo@@ +
-* %red%Set up the IF inputs.  +
-** %red%For either single ​S-band polarisation, ​use\\ +
-%red%@@dbbcifa=4,​agc,​2@@\\ +
-%red%@@dbbcifb=2,​agc,​2@@\\ +
-%red%@@pps_sync@@ +
-* %red%Confirm that the crossover switches are in the correct position. For SLCP, the switches should ​be direct, while SRCP you need to have the switches crossed. If you do change this, ''​please leave a note for the next observer!''​. To check the status, it's easiest to do this by starting up a system monitor. Connect to ops4 with @@shh -observer@ops4@@ and run @@monitor_system.pl@@. Select the relevant telescope & check the settings of the "Cross-over switches"​ +
-* Check the mk5b_mode line in the @@/​usr2/​proc/​v999ake.prc@@ file. For 4 channels only, it should read as @@mk5b_mode=ext,​0x000000FF,​0@@ while for 8 it should be @@mk5b_mode=ext,​0x0000FFFF,​1@@.+
  
-!!!S-band, dual polarisation - 4 channels maximum +Here's an example ​of S-RCP and X-RCP setup:
-This is the configuration that is most fraught with hazard. It requires either physical recabling ​of the dbbc to put the correct ​S-band inputs into CoMos A and B, or requires the following (untested) procedure. If you use recabling, follow the X-band notes but use 1900 when working out dbbc frequencies.+
  
-* Create a new configuration file in @@C:​\DBBC_CONF@@ of dbbcke if needed. If the experiment shares a configuration with a previous experiment (same frequencies,​ polarisations,​ channel order) then you should be able to use that. Otherwise, read on.  +<​code>​ 
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequencies. Put all of the channels at one frequency in lines 1-4 and have lines 9-12 for the other polarisation. If the schedule shows the channels as alternating between RCP and LCPtell the LBA chat (Cormac and Chris by email) that the recorded channel ordering will be different. +define ​ ifd01         ​13075124605x ​            
-** Start by checking the listed frequencies of each channel on the ATNF Wiki. In the corresponding entry in your experiment'​s config file change the frequency to (lower band edge-1900). As an exampleif channel ​1's lower band edge is 2209 MHz then the first line in the @@dbbc_config_file_v999a.txt@@ is then @@1 dbbc2.bit 309.00 16@@ as is the ninth line. If channel 2's lower band edge is 2225 MHz then the second and tenth lines will be @@1 dbbc2.bit 325.00 16@@. +ifa=1,agc,1,38000 
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v999a.txt@@ +ifc=2,agc,2,36000 
-* %red%Reconfigure the DBBC with @@reconfig@@ +lo= 
-* %red%Use the @@DBBC Client@@ to send the command @@dbbcform=geo@@ +lo=loa,7600.00,usb,rcp,off 
-* %red%Set up the IF inputs.  +lo=lob,1900.00,usb,rcp,off 
-** %red%Send these commands:​\\ +enddef 
-%red%@@dbbcifa=4,agc,2@@\\ +</​code>​
-%red%@@dbbcifc=2,agc,2@@\\ +
-%red%@@pps_sync@@ +
-* %red%Confirm that the crossover switches are in the correct positionFor SLCP/SRCPthe switches should be directwhile for SRCP/SLCP you need to have the switches crossed. If you do change this''​please leave a note for the next observer!''​. To check the statusit's easiest to do this by starting up a system monitorConnect to ops4 with @@shh -X observer@ops4@@ and run @@monitor_system.pl@@. Select the relevant telescope & check the settings of the "​Cross-over switches"​ +
-* Edit the mk5b_mode line in the @@/​usr2/​proc/​v999ake.prc@@ file. For 4 channels onlyit should read as @@mk5b_mode=ext,0x00F0000F,1@@.+
  
-!!!S-banddual polarisation ​- 8 channels maximum +As BBCs 1 4 are assigned to CoMo A- 8 to B, 9 12 to C and 13 - 16 to D, you want to set up BBCs 01 - 04 for RCP and 09 12 for S RCP. e.g.
-This is the configuration that is most fraught with hazard. It requires either physical recabling of the dbbc to put the correct S-band inputs into CoMos A and Bor requires the following (untested) procedure. If you use recabling, follow the X-band notes but use 1900 when working out dbbc frequencies.+
  
-* Create a new configuration file in @@C:​\DBBC_CONF@@ of dbbcke if neededIf the experiment shares ​configuration with a previous experiment (same frequenciespolarisations,​ channel order) then you should be able to use that one in the next step. Otherwise, read on.  +<​code>​ 
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequencies. Put all of the channels at one polarisation in lines 1-4 and have lines 9-12 for the other polarisation. If the schedule shows the channels as alternating between RCP and LCPtell the LBA chat (Cormac and Chris by email) that the recorded channel ordering will be different+define ​ dbbc01d ​      ​13075124605x ​            
-** Start by checking the listed frequencies of each channel on the ATNF Wiki. In the corresponding entry in your experiment'​s config file change the frequency to (lower band edge-1900). Using [[http://​www.atnf.csiro.au/​vlbi/​wiki/​index.php?​n=LBAApr2012.V444B|v444b]] as an examplechannel 1's lower band edge is 2244 MHzThe first line in the @@dbbc_config_file_v444b.txt@@ is then @@1 dbbc2.bit 344.00 16@@The second RCP channel has a lower band edge of 2260 MHz and so the second line is @@1 dbbc2.bit 360.00 16@@Lines 9-12 in the file are the same as lines 1-4 (as this sets these channels to matched frequencies) +bbc01=793.00,a,16.00 
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v444b.txt@@ +bbc02=809.00,a,16.00 
-* %red%Reconfigure the DBBC with @@reconfig@@ +bbc03=825.00,a,16.00 
-* %red%Use the @@DBBC Client@@ to send the command @@dbbcform=geo@@ +bbc04=841.00,a,16.00 
-* %red%Set up the IF inputs +bbc09=300.00,c,16.00 
-** %red%Send these commands:​\\ +bbc10=316.00,c,16.00 
-%red%@@dbbcifa=4,agc,2@@\\ +bbc11=332.00,c,16.00 
-%red%@@dbbcifc=2,​agc,​2@@\\ +bbc12=348.00,c,16.00 
-%red%@@pps_sync@@ +enddef 
-* %red%Confirm that the crossover switches are in the correct positionFor SLCP/SRCPthe switches should be directwhile SRCP/SLCP you need to have the switches crossedIf you do change this, ''​please leave a note for the next observer!''​. To check the status, it's easiest to do this by starting up a system monitor. Connect to ops4 with @@shh -X observer@ops4@@ and run @@monitor_system.pl@@. Select the relevant telescope & check the settings of the "​Cross-over switches"​ +</code>
-* Edit the mk5b_mode line in the @@/usr2/​proc/​v999ake.prc@@ file to read @@mk5b_mode=ext,​0x0FF000FF,​1@@+
  
-!!!S/​X-band,​ single polarisation +The Mark5 mode needs to pass though BBCs 1-and 12so it should ​look like this: 
-* Create a new configuration file in @@C:​\DBBC_CONF@@ of dbbcke if needed. If the experiment shares a configuration with a previous experiment (same frequencies,​ polarisations,​ channel order) then you should be able to use that. Otherwise, read on.  +<​code>​ 
-** Copy the basic layout from @@dbbc_config_file_lba.txt@@ to your new file and then edit the frequencies. Start by checking the listed frequencies of each channel on the ATNF Wiki. In the corresponding entry in your experiment'​s config file change the frequency to (lower band edge-7600). Using [[http://​www.atnf.csiro.au/​vlbi/​wiki/​index.php?​n=LBASep2012.V469a|v469a]] as an example, channel 1's lower band edge is 8409 MHz. The first line in the @@dbbc_config_file_v469a.txt@@ is then @@1 dbbc2.bit 809.00 16@@. Repeat for all needed channels and leave unused channels alone. +mk5b_mode=ext,​0x0FF000FF,​1 
-* %red%Load the configuration into the DBBC with the @@DBBC Client@@ command @@load=dbbc_config_file_v469a.txt@@ +</​code>​
-* %red%Reconfigure the DBBC with @@reconfig@@ +
-* %red%Use the @@DBBC Client@@ ​to send the command @@dbbcform=geo@@ +
-* %red%Set up the IF inputs. I've assumed that the observing frequencies for X-band are between 8112 and 8624 MHz which is normal for the LBA.  +
-** %red%Send these commands:​\\ +
-%red%@@dbbcifa=1,​agc,​1@@\\ +
-%red%@@dbbcifc=2,​agc,​2@@\\ +
-%red%@@pps_sync@@ +
-* %red%For RCP, confirm that the crossover switches are in the direct position. It's easiest to do this by starting up a system monitor. Connect to ops4 with @@ssh -X observer@ops4@@ ​and run @@monitor_system.pl@@. Select the relevant telescope & check the settings of the "Cross-over switches"​. For LCPthe crossover switches ​should ​be crossed. +
-* Check the mk5b_mode line in the @@/​usr2/​proc/​v469ake.prc@@ file. For 8 channels it should be @@mk5b_mode=ext,​0x0FF000FF,​1@@.+
  
  
/home/www/auscope/opswiki/data/attic/operations/documentation/lba_dbbc_config.1363840849.txt.gz · Last modified: 2013/03/21 04:40 by Jim Lovell