Detector DAQ Setup

• Gate to ADC MUST NOT be disconnected!!!

The ADC hardware trigger, soft triggers the acquisition for the rest of the CAMAC crate which happens to be the TD2 & 4s for the readout of the whole CBPM system (further down the timing line) and the magnet system - so definitely don't unplug.

• The gate delay and width can however be adjusted as long as the gate is sufficiently wide for the others to trigger.
• There is a 'T' in the trigger line. The gate can be monitored on an oscilloscope using 1MOhm impedance (effectively passive to 50 Ohm).

Setup

• After breaking and fixing readout for everyone else, adjust gate width and delay to overlap with PMT pulses from each detector
• Raised voltage slowly during beam time on each pmt until between 500mV - 1V pulses were seen (from experience).
• 900V was sufficient and there was strong signal in both at 1kV.
• Timing is shown in the picture below.
• Data is in dat/general/20150616_detector_gate_setup/
• Green is detector 2 (new location further upstream)
• Yellow is detector 1 (laserwire location)
• Blue is the gate signal - note ringing oscillations are from mismatch into 1MOhm impedance

-- Public.LaurieNevay - 17 Jun 2015