ADF-2 Card Re-Work to Compensate for Unfixable BLS Signals ----------------------------------------------------------- Original Rev. 24-July-2006 Current Rev. 26-July-2006 A few BLS signals have broken signal pins at the BLS backplane. We can not repair these broken pins without replacing the BLS crate backplane. Because of these broken backplane signal pins the ADF-2 card receives only 1/2 of the normal BLS signal amplitude. To compensate for this we modify the ADF-2 card as described below. In addition to the broken BLS crate signal pins there are a number of broken BLS crate backplane ground pins. These broken BLS backplane ground pins leave the BLS cable shield floating at the Platform end and thus distort the BLS signal sent to the L1 Cal Trigger. We compensate for the broken ground pins by opening the BLS cable connector at the Platform end and soldering together all of the shield grounds. The BLS crate backplane pins were broken at the beginning of Run II because the managers insisted on using untrained people to reinstall the BLS cables. Re-Work to compensate for the problem with the -2,1 HD BLS signal ----------=======-------------------- -2,1 HD is handled by the ADF-2 card in slot #10 of crate "A", i.e. crate 0. This is a species "A" ADF-2 card that handles eta -1:-4 phi 1:4. Thus -2,1 HD is handled by channel 4 on this ADF-2 card. The problem with the -2,1 HD BLS signal is: Broken pin on HD+ signal. BLS HD- signal is OK. Thus what we want to do is to disconnect the broken HD+ signal at the input to this channel and double the differential gain of the analog section of this channel. To disconnect the broken the HD+ input do the following: Remove input coupling capacitor C222. To double the gain of the analog section of this channel do the following: Remove resistors R225 and R226 which are currently 511 Ohm and replace them with 255 Ohm resistors. Re-Work to compensate for the problem with the -2,5 HD BLS signal ----------=======-------------------- -2,5 HD is handled by the ADF-2 card in slot #11 of crate "A", i.e. crate 0. This is a Meastro ADF-2 card. This is a species "A" ADF-2 card that handles eta -1:-4 phi 5:8. Thus -2,5 HD is handled by channel 4 on this ADF-2 card. The problem with the -2,5 HD BLS signal is: Broken pin on HD- signal. BLS HD+ signal is OK. Thus what we want to do is to disconnect the broken HD- signal at the input to this channel and double the differential gain of the analog section of this channel. To disconnect the broken the HD- input do the following: Remove input coupling capacitor C221. To double the gain of the analog section of this channel do the following: Remove resistors R225 and R226 which are currently 511 Ohm and replace them with 255 Ohm resistors. Re-Work to compensate for the problem with the +16,17 HD BLS signal ----------=========------------------ +16,17 HD is handled by the ADF-2 card in slot #14 of crate "C", i.e. crate 2. This is a species "D" ADF-2 card that handles eta +13:+16 phi 17:20. Thus +16,17 HD is handled by channel 12 on this ADF-2 card. The problem with the +16,17 HD BLS signal is: Broken pin on HD- signal. BLS HD+ signal is OK. Thus what we want to do is to disconnect the broken HD- signal at the input to this channel and double the differential gain of the analog section of this channel. To disconnect the broken the HD- input do the following: Remove input coupling capacitor C621. To double the gain of the analog section of this channel do the following: Remove resistors R625 and R626 which are currently 1370 Ohm and replace them with 685 Ohm resistors. Re-Work to compensate for the problem with the -13,18 EM BLS signal ----------=========------------------ -13,18 EM is handled by the ADF-2 card in slot #2 of crate "D", i.e. crate 3. This is a species "D" ADF-2 card that handles eta -13:-16 phi 17:20. Thus -13,18 EM is handled by channel 1 on this ADF-2 card. The problem with the -13,18 EM BLS signal is: Broken pin on EM+ signal. BLS EM- signal is OK. Thus what we want to do is to disconnect the broken EM+ signal at the input to this channel and double the differential gain of the analog section of this channel. To disconnect the broken the EM+ input do the following: Remove input coupling capacitor C52. To double the gain of the analog section of this channel do the following: Remove resistors R55 and R56 which are currently 1370 Ohm and replace them with 685 Ohm resistors. The following is background information for this work ----------------------------------------------------- Recall: TT Eta is numbered +- 1:20 and TT Phi is numbered 1:32 The relative eta,phi on a given ADF-2 card, its ADF-2 card channel number, and the start of the reference designator range for that channel are the following: Reference Designators ADF-2 Card Relative ----------------------- Channel eta,phi EM HD ---------- -------- --------- --------- 0 0,0 1 21 1 0,1 51 71 2 0,2 101 121 3 0,3 151 171 4 1,0 201 221 5 1,1 251 271 6 1,2 301 321 7 1,3 351 371 8 2,0 401 421 9 2,1 451 471 10 2,2 501 521 11 2,3 551 571 12 3,0 601 621 13 3,1 651 671 14 3,2 701 721 15 3,3 751 771 Map of TT eta's to relative eta's on an ADF-2 card: TT eta of 1, 5, 9, 13, 17 is a relative eta of 0 TT eta of 2, 6, 10, 14, 18 is a relative eta of 1 TT eta of 3, 7, 11, 15, 19 is a relative eta of 2 TT eta of 4, 8, 12, 16, 20 is a relative eta of 3 Map of TT phi's to relative phi's on an ADF-2 card: TT phi of 1, 5, 9, 13, 17, 21, 25, 29 is a relative phi of 0 TT phi of 2, 6, 10, 14, 18, 22, 26, 30 is a relative phi of 1 TT phi of 3, 7, 11, 15, 19, 23, 27, 31 is a relative phi of 2 TT phi of 4, 8, 12, 16, 20, 24, 28, 32 is a relative phi of 3 When refering to the analog circuit diagrams for the ADF-2 card remember that EM reference designators start at xy1 or x51 and that HD reference designators start at x21 or x71. For the analog circuit diagram see: www.pa.msu.edu/hep/d0/ftp/run2b/l1cal/hardware/adf_2/drawings/ adf_2_differential_amp.pdf For the reference designator map see: www.pa.msu.edu/hep/d0/ftp/run2b/l1cal/hardware/adf_2/manufacturing/ adf_2_inspect_top.pdf adf_2_inspect_bot.pdf To know what slot in which crate has the ADF-2 card that services a given range of TT eta,phi refer to: www.pa.msu.edu/hep/d0/ftp/run2b/l1cal/hardware/adf_2/cards_and_crates/ adf_crate_card_layout.txt The following is the current list of broken BLS Crate backplane pins as of 25-July-2006. - From the log book entry for 10:13-DEC 2002. We have broken pins at: -2,1 HD M104 Broken BLS Backplane center conductor pin. BLS HD- signal is OK. Broken pin on HD+ signal. -2,5 HD M104 Broken BLS Backplane center conductor pin. BLS HD+ signal is OK. Broken pin on HD- signal. - From email from Dean on 17-May-2006 we have another broken pin at: +16,17 HD M109 Broken BLS Backplane center conductor pin. BLS HD+ signal is OK. Broken pin on HD- signal. - From email from Selcuk on 13-July-2006 and from Dean on 26-July-2006 -13,18 EM M110 Broken BLS Backplane center conductor pin. BLS EM- signal is OK. Broken pin on EM+ signal.