Minutes of the forward endcap EMC meeting, 18th of August 2014, SeeVogh, 14:00 - 16:00

Presence

• Bochum: Cathrina, Claudius, Fritz-Herbert. Malte, Matthias, Patrick, Tobias, Tom
• Bonn: Ulrike, Christoph
• Groningen: Myroslav
• Uppsala: Pawel

General

Successful beam tests at ELSA with Proto192 (VPTT and APD). Data analysis in progress.

Shaper

• KVI VME shaper produces negative pulses. This is due to an overload of the shaper (too large signals) (Myroslav).
• The Bochum group would like to test the new shaper design independent of the ADC design. Bonn will produce a 4 channel board according to the latest design of Pawel. Input: preamp signal. Output: differential for ADC. The new shaper has passive splitting of high/low gain and exist with two different shaping times for high and lower rates.
• The pulses from the red and green lightpulser LEDs are considerable longer. The feature extraction has to reconstruct these properly. Matthias will send waveforms to Myroslav and Pawel.

Cables

The beam test used the new distribution PCBs for each alveoli. For the APD alveoli the space not enough, thus design changes are needed.

1. Use only one ground for 2 HV (APD)
2. Use thinner, more flexible HV cables (Christoph will select them)
3. Signal cables need to be selected
   1. Money is available this year. Need to know within 2 weeks if money can be spent (Ulrike)
   2. Cables are maximum 4 m long (if going from PCB in cold to ADC crate backplane)
   3. The ADC has a Samtex backplate connector (Pawel)
   4. Options
      1. Environflex 1.8 mm (probably too much space required)
      2. NEXAN 1.17 mm
      3. Samtex microcoax
   5. Actions:
      1. Christoph will sent two bunches of 16 micro coax cables with concoctor to Bochum
      2. Bochum will measure the damping of preamp signals for all three types of cables
      3. Bochum will look into the routing of the signal cables
4. Low voltage distribution: There will be 6 independent LV connections (each about 50A per voltage). The distribution should be done on the edge with cables to each alveole PCB.
5. Sensor cables: flat cables
6. See also Cables

A.o.B.

• Matthias will set up a mailing list. Please send your requests to Fritz-Herbert.

-- FritzHerbertHeinsius - 19 Aug 2014