Hello,
At ESRF we now re-installed a high quality numeric BEAM PHASE monitor that is achieving very good & useful results.
It is based on a simple Spark-BPM electronics, using the available I and Q buffers in that device.
The resolution is about 1millidegree and it can measure at sampling speeds upto Turn-by-Turn rate (2.8us ESRF)
If you want more information please contact Elena or Kees, or download the available pdf.