Test Tube Activities at Ohio State (8/5/03) Two (very useful) sub-group meetings after last weekly meeting –Mechanics (Bill, Lu, Mark, Jim, Charlie, Klaus) -> see Mark’s report –Electronics (Angelo, Klaus) OSU designes HV board, Distribution board (both inside AL box) Angelo will bring 6 (8 if possible) input protection circuits for anode signals Angelo will modify one FE board to receive (negative) anode signals Two (fine pitch) signal cables from AL box to “mini crate” 75 ft of Amphenol/Spectra Strip received –With green (round) jacket, shielding –20 pairs –Sent to SLAC (Charlie) Kerpen HV cable is still not available. –SLAC (PCK) will try to obtain enough RPC HV cable for 8 HV lines from electronic hut to BaBar. Need to design HV transition box (8 short HV cables will be attached (soldered) to HV distribution PC board in AL box. Connect to long HV cables outside of magnet)

HV Distribution Board HV capacitors Cable Connector Anode signal readout Layout complete, 1 board for both tubes, Flat cable connector in hand Will be tested with OSU tubes Send to Princeton (or SLAC if too late)

Signal Distribution Board Allow for: baseline (single ended), pseudo-differental, and fully differential configuration Layout (almost) complete Receive cathode signals (16) via short twisted pair stub cables 16 ch. Output (fine pitch twisted flat cable)

What will we need? 8 HV channels with current monitoring, overcurrent trip HV cables, HV connector box Low voltage: +/-5 V, 300 mA in AL box Low voltage: +/-5 V near mini crate (FE board, diff. Receiver) Install signal cables (on their way to Charlie) -> Need to identify the location of a suitable FEC crate! –This defines the location of the infrastructure connections in the AL box –Need this today! –Note: Anode and Phi signals, HV, low voltage and gas (in+out) will be all on the same side. The tubes will be shifted toward the other end of the AL box to make sufficient room for the infrastructure stuff. Coax cables from detector (mini crate location) to outside the shielding wall so that we can view signals with beams on