Summary of the Recycler Ring BPM Meeting and follow up - Brajesh Choudhary Date: 01st October 2002 Time: 2:45PM in Huddle ---------------------------- AGENDA: General Discussion on test evaluation of the EchoteK Digital Receiver Board. ---------------------------- In Attendance: 1. Brajesh Choudhary 2. James Crisp 3. Bill Foster 4. Martin Hu 5. Peter Limon 6. Craig Mcclure 7. Shekhar Mishra 8. Stephen Pordes 9. Peter Prieto 10.Marc Ross (**) 11.Vic Scarpine 12.Warren Schappert 13.Jim Sebek (**) 14.Till Straumann (**) 15.Peter Wilson 16.Sergio Zimmermann 17.djm@slac.stanford.edu (**) (**) - Visitors from SLAC ----------------------------- PETER PRIETO presented the test status of the EchoTek digital receiver board. Two digital receiver board came from EchoTek. One did not work. It was sent back to EchoTek. The second board is beind tested. The board was tested for background flash, flash and turn by turn mode. The board works but the DMA on the board failed. It did work earlier. DUANE VOY and TOM MEYER are working around it to modify the front end software and readout. No time estimate was given. Hopefully will be done in couple of days. *** 2nd October 2002, Summary of E-Mail fron DUANE VOY ******* They (PETER, TOM and DUANE) just finished working on 4 channels (one digital receiver board from EchoTek). They plan to coordinate with Craig Mcclure and install the board at MI-50 on 3rd Oct. They expect the system to be operational by the end of the day.********* *** 2nd October 2002, Summary of E-Mail from TOM MEYER ******* He hopes to have a four BPM test at MI-50 sometime on Friday (4.OCT.02). **** *** 3rd October 2002, Summary of E-Mail from JIM CRISP ****** Many software problems were fixed. The VMS64X crate loaned to the SLAC/BLT effort has been returned and one of the digital receivers will be moved to the ring on thursday (3rd Oct.). They expect to measure the beam positions on Friday (4th Oct.) The other digital receiver card will arrive by Friday (has arrived today, 4th Oct) and will be used to continue work in the transfer gallery. Once its functionality is assured it will be moved into the ring for evaluation. **** *** 4th October 2002, E-Mail from PETER PRIETO ******* The digital down coveter board is being evaluated by Tom Meyer and Duane Voy. As installed in MI-50 the board should perform flash, turn-by-turn and background flash. What is left to do is to adjust timing with respect to the beam with 2.5MHz bunches in the recycler. I would be ready to do this at your convenience. ************* PETER PRIETO described his plan to change the present preamp switches with JFET switch. From PETER PRIETO "The preamp modifications consist of removing all resonant components, that is chokes. Replace the 1.5KOhn shunting resistor with a 150 Ohm resistor. Add a lead network in series with the 150 Ohm to lower the corner frequency and increase the signal size for 89KHz by a factor of 5." It was agreed that if the test boards meet the specification, logamps on 216 BPMs in RR and 14 BPMs each in both the tranfer lines will be replaced. That will require 216+2X14=244 channels or 61 digital receiver board. Warren Shappert needs 4 digital boards for his BLT's. It was agreed to buy 70 boards if the board meets the specification. Preamps associated with these 244 channels will be modified from resonant mode to non-resonant mode. It was also agreed that all the preamp switches will be replaced with JFET switch so that there is no possibility of switch failure due to radiation. ******JIM CRISP wrote back on 4th October "Unless we have to, I will not burden the project with upgrading preamps that will not be used". ********** MARTIN HU presented the functional specification and requirements that the updated BPM system using digital receiver board should meet. It led to lively discussion. Marc Ross from SLAC talked about beam based alignment technique to measure absolute position measurement of the beam using quadrupole shunting method with powered quads. He also talked about calibrating the BPM system. Jim Sebek talked about feedback system and the resolution of the BPM.