1. January 19, 2006PEP TFB R.Akre PEP II Transverse Feedback System Ron Akre William Colocho Anatoly Krasnykh Vojtech Pacak Dmitry Teytelman Uli Wienands MAC January 18, 2006

2. January 19, 2006PEP TFB R.Akre PEP II Transverse Feedback System The PEP TFB system takes the vector sum of 2 BPMs, delays the signal by the remainder of 1 turn and delivers a kick to the beam the next time around. Two stripline kickers, one for X and one for Y, are used.

3. January 19, 2006PEP TFB R.Akre PEP II TFB Highlights for Run 5 New Moly Kicker Electrodes and larger, 7/16 DIN, connectors allow higher current running in LER – LER has run for 3 days at 3 Amps. Added phase shifters to HER receivers to independently phase X and Y Removal of orbit offset electronics increases gain in receiver chassis. Replace HER BPM Attenuators with higher power units The new data acquisition system and analysis software is running and collecting Gigabytes of data. New LBNL 2 Tap Filter / Delay installed in LER Y since August and in HER for a few weeks in December G-proto in LER Y for a week in September and LER X for a few weeks in December

4. January 19, 2006PEP TFB R.Akre PEP II Transverse Feedback System Run 5 Resolved Hardware Problems 18 Log Entries associated with hardware problems –16 Power Amp Problems 14 transistors 5 regulator boards –1 High Power Filter Blown: LER Y- –1 Failed BPM Attenuators: LER 2C

5. January 19, 2006PEP TFB R.Akre PEP II TFB Receiver Orbit offset correction are done by changing beam orbit to minimize dX and dY signals. Receiver chassis have been modified to eliminate orbit offset adjustment and give more gain. Manual phase shifters added to phase HER X and HER Y independently

6. January 19, 2006PEP TFB R.Akre PEP II TFB Digital Delays Lawrence Berkeley Laboratory Phase 1: 2 - 12 bit ADC to clock data into FPGA at 238MHz Two tap filter with 1 turn delay plus variable delay 238MHz DAC with differential output Programmable through COM port. Completed – Installed in LER Y August 2005 Phase 2: Record 16MS, 70mS, of data to external memory Three trigger modes Grow/ Damp Measurements Fault File Data Software trigger to capture data during running On board EPICS control with Ethernet for programming Final Software being completed Principal Investigators: Walter Barry and John Byrd Alex Chin, Larry Doolittle, Alex Ratti, Jonah Weber

7. January 19, 2006PEP TFB R.Akre PEP II TFB Digital Delays New Digital Delays – 2 tap filter and diagnostics are being developed by LBNL Jonah Weber LBNL

8. January 19, 2006PEP TFB R.Akre PEP II TFB Power Amplifiers and Filters Power Amplifiers Reliability of the power amplifiers still remain a large concern. Each of the 8 amplifiers has 8 power transistors summed for the output. During this run 5 so far we have lost about 14 output power transistors. Largest reliability concern During the past down time all the amplifiers have been tested and repaired The orbit offsets and phase transients cause the amplifiers to run close to saturation. The new digital delay two tap filters eliminate orbit offsets and greatly reduce power requirements in the amplifers. Filters So far only 1 filter failure – the new 7/16 DIN connector in LER Y- did not fail, but internal LC components did.

9. January 19, 2006PEP TFB R.Akre PEP II TFB Kickers Uli Wienands, Anatoly Krasnykh, Artem Kulikov, Jay Langton, Many Others New kickers with moly electrodes, redesigned coax to stripline transition, and 7/16 DIN connectors have been installed in LER.

10. January 19, 2006PEP TFB R.Akre PEP II TFB Data Acquisition System GAGE 82G PCI 8bit 2GHz 2 Channel Digitizer 16Mb Memory 2 Cards 4 Channels – HER X and Y and LER X and Y 3 rd card is on order to monitor other signals GAGE card is clocked at 238MHz bunch frequency Inputs are from vector sum out of Analog Signal Processor for X and Y Programmable triggers: Inputs from HER / LER Fault, HER / LER Injection, HER / LER Software. Output trigger for grow/damp measurements. PEP TFB TRIGGER CHASSIS

11. January 19, 2006PEP TFB R.Akre PEP II TFB Data Acquisition System Files are stored in central NFS space Compiled MatLab routines for analysis of data sets are run from a GUI

12. January 19, 2006PEP TFB R.Akre PEP II TFB Data Acquisition System Analysis Software Display All Data Display Selected Data Plot RMS FFT Plot Modes Plot Mode Phase Plot Mode Growth Fit High Resolution FFT High Resolution FFT 2 Plot Spectrogram W. Colocho, V. Pacak Compiled MatLab Software Run from GUI

13. January 19, 2006PEP TFB R.Akre 12-08-05 21:17 ~2200mA LER LER CURRENT X Y XY

14. January 19, 2006PEP TFB R.Akre Grow Damp Measurements August 16, 2005 Mode -1

15. January 19, 2006PEP TFB R.Akre Grow Damp Measurements August 16, 2005 0.74 1/mS 0.96 1/mS 0.69 1/mS0.63 1/mS

16. January 19, 2006PEP TFB R.Akre Grow Damp Measurements August 16, 2005

17. January 19, 2006PEP TFB R.Akre Grow Damp Measurements August 16, 2005

18. January 19, 2006PEP TFB R.Akre PEP II TFB Concerns for Higher Current Running Feedback Gain and Output Power Plan to do grow / damp measurements in both HER and LER. LBNL two tap filters have shown large increases in system gain, postponing the need for larger power amplifiers. The new delays require less rack space if larger power amps are required. Filters are currently working well – 1 failures with new connector Only 1 filter, LER Y-, has 7/16DIN connector – the rest use N connectors (This same filter is the only one which failed during this run) Kickers New Moly electrodes in LER, they have handled up to 3 amps and are expected to work to 4.5 amps. 7/16DIN Feed-through connectors replaced SC, and eliminate SC to N adapters. As the bunch length shortens higher frequencies of beam induced power will need to be directed to proper loads. Measurements of beam induced power from kicker to amplifiers need to be done.

19. January 19, 2006PEP TFB R.Akre PEP II TFB Near Term Run 5 Tasks Set up collaboration with LBNL to assist with measurements Measure power reflected to amplifier from kicker –Especially LER Y- Grow / damp measurements both planes of both rings Transfer function measurements in both rings Install 2 tap filters in both planes of both rings Install 3 rd GaGe card to monitor 2 additional channels